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Extinction and the U.S. Endangered Species Act

Noah greenwald.

1 Center for Biological Diversity, Portland, OR, USA

Kieran F. Suckling

2 Center for Biological Diversity, Tucson, AZ, USA

Brett Hartl

3 Center for Biological Diversity, Washington, DC, USA

Loyal A. Mehrhoff

4 Center for Biological Diversity, Honolulu, HI, USA

Associated Data

The following information was supplied regarding data availability:

The raw data are available in a Supplementary File and include a complete list of the species we identified as extinct or possibly extinct along with all supporting information.

The U.S. Endangered Species Act is one of the strongest laws of any nation for preventing species extinction, but quantifying the Act’s effectiveness has proven difficult. To provide one measure of effectiveness, we identified listed species that have gone extinct and used previously developed methods to update an estimate of the number of species extinctions prevented by the Act. To date, only four species have been confirmed extinct with another 22 possibly extinct following protection. Another 71 listed species are extinct or possibly extinct, but were last seen before protections were enacted, meaning the Act’s protections never had the opportunity to save these species. In contrast, a total of 39 species have been fully recovered, including 23 in the last 10 years. We estimate the Endangered Species Act has prevented the extinction of roughly 291 species since passage in 1973, and has to date saved more than 99% of species under its protection.

Introduction

Passed in 1973, the U.S. Endangered Species Act (ESA) includes strong protections for listed threatened and endangered species and has helped stabilize and recover hundreds of listed species, such as the bald eagle and gray whale ( Taylor, Suckling & Rachlinski, 2005 ; Schwartz, 2008 ; Suckling et al., 2016 ). In part because of its strong protections, the ESA has engendered substantial opposition from industry lobby groups, who perceive the law as threatening their profits and have been effective in generating opposition to species protections among members of the U.S. Congress. One common refrain from opponents of the ESA in Congress and elsewhere is that the law is a failure because only 2% of listed species have been fully recovered and delisted ( Bishop, 2013 ).

The number of delistings, however, is a poor measure of the success of the ESA because most species have not been protected for sufficient time such that they would be expected to have recovered. Suckling et al. (2016) , for example, found that on average listed birds had been protected just 36 years, but their federal recovery plans estimated an average of 63 years for recovery. Short of recovery, a number of studies have found the ESA is effectively stabilizing or improving the status of species, using both biennial status assessments produced by the U.S. Fish and Wildlife Service for Congress and abundance trends ( Male & Bean, 2005 ; Taylor, Suckling & Rachlinski, 2005 ; Gibbs & Currie, 2012 ; Suckling et al., 2016 ).

In addition to recovering species, one of the primary purposes of the ESA is to prevent species extinction. Previous studies indicate the ESA has been successful in this regard ( McMillan & Wilcove, 1994 ; Scott et al., 2006 ). As of 2008, the ESA was estimated to have prevented the extinction of at least 227 species and the number of species delisted due to recovery outnumbered the number of species delisted for extinction by 14–7 ( Scott et al., 2006 ). In this study, we identified all ESA listed species that are extinct or possibly extinct to quantify the number of species for which ESA protections have failed and use these figures to update the estimated number of species extinctions prevented. This is the first study in over 20 years to compile data on extinction of ESA listed species, providing an important measure of one of the world’s strongest conservation laws ( McMillan & Wilcove, 1994 ).

To identify extinct or possibly extinct ESA listed species, we examined the status of all 1,747 (species, subspecies and distinct population segments) U.S. listed or formerly listed species, excluding species delisted based on a change in taxonomy or new information showing the original listing to have been erroneous. We determined species to be extinct or possibly extinct based on not being observed for at least 10 years, the occurrence of adequate surveys of their habitat, and presence of threats, such as destruction of habitat of the last known location or presence of invasive species known to eliminate the species.

To differentiate extinct and possibly extinct species we relied on determinations by the U.S. Fish and Wildlife Service, IUCN, species experts and other sources. In most cases, these determinations were qualitative rather quantitative. Species were considered extinct if surveys since the last observation were considered sufficient to conclude the species is highly likely to no longer exist, and possibly extinct if surveys were conducted after the last observation, but were not considered sufficient to conclude that extinction is highly likely ( Butchart, Stattersfield & Brooks, 2006 ; Scott et al., 2008 ).

Source information included 5-year reviews, listing rules and critical habitat designations by the U.S. Fish and Wildlife Service (for aquatic and terrestrial species) or NOAA Fisheries (for marine species), published and gray literature, personal communication with species experts and classifications and accounts by NatureServe, IUCN and the Hawaiian Plant Extinction Prevention program. For each species, we identified year of listing, year last seen, NatureServe and IUCN ranking, taxonomic group, and U.S. Fish and Wildlife Service region. For species last seen after listing, we also searched for abundance estimates at time of listing in order to give a sense of likelihood of survival regardless of ESA protection.

Following previously developed methods, we estimated the number of species extinctions prevented by the ESA by assuming that listed threatened and endangered species have a comparable extinction risk to IUCN endangered species, which was estimated as an average of 67% over 100 years ( Mace, 1995 ; Schwartz, 1999 ; Scott et al., 2006 ). We believe this estimate of extinction risk is conservative based on similarity of IUCN criteria to factors considered in ESA listings, observed low numbers for species at time of ESA listing and observed correspondence between ESA listed species and species classified as endangered or critically endangered by the IUCN ( Wilcove, McMillan & Winston, 1993 ; Wilcove & Master, 2005 ; Harris et al., 2012 ). Presumed extinction risk was then multiplied by the number of extant listed species and the proportion of a century in which species were protected by the ESA. Previous studies used the length of time the ESA has been in existence (1973-present) for the proportion of a century species have been protected ( Schwartz, 1999 ; Scott et al., 2006 ), but because many species have not been protected the entire 45 years the law has existed, we instead used the more conservative average length species were protected (25 years). This corresponds to the following formula:

We identified a total of 97 ESA listed species that are extinct (23) or possibly extinct (74). Of these, we found 71 extinct (19) or possibly extinct (52) species were last observed before they were listed under the ESA and thus are not relevant to determining the Act’s success in preventing extinction ( Table S1 ). These species were last seen an average of 24 years before protection was granted with a range of one to more than 80 years prior.

A total of 26 species were last seen after listing, of which four are confirmed extinct and 22 are possibly extinct ( Table S2 ). On average, these species were last seen 13 years after listing with a range of 2–23 years. We were able to find an abundance estimate at the time of listing for 19 of these species, ranging from one individual to more than 2,000 with an average of 272. In several cases, these estimates were based on extrapolations from very few sightings.

The distribution of extinct and possibly extinct species was non-random with 64 of the 97 species from Hawaii and other Pacific Islands, followed by 18 from the southeast ( Fig. 1 ). This was also the case for taxonomy. A total of 40 of the 97 species were mollusks dominated by Hawaiian tree snails and southeast mussels, followed by birds (18) and plants (17) ( Fig. 2 ).

Extinct or possibly extinct listed species by taxonomic group.

Extinct or possibly extinct listed species by U.S. Fish and Wildlife Service Region.

We identified several other species that have been missing for more than 10 years, but for which there has not been any effective surveys and thus classifying them as possibly extinct did not seem appropriate, including two Hawaiian yellow-faced bees ( Hylaeus facilis and Hylaeus hilaris ) (K. Magnacca, 2018, personal communication) and Fosberg’s love grass ( Eragrostis fosbergii ) ( U.S. Fish and Wildlife Service, 2011 ). If indeed extinct, all three were lost prior to protection under the ESA.

Including updated figures for number of listed species, time of protection and species extinctions, we estimate the ESA has prevented the extinction of roughly 291 species in its 45 year history. Based on the number of confirmed extinctions following listing, we further estimate that the ESA has to date prevented the extinction of more than 99% of species under its protection. To date, a total of 39 species have been delisted for recovery compared to four species that are extinct and 22 that are potentially extinct.

The few number of listed species that have gone extinct following protection combined with an estimated 291 species for which extinction was prevented demonstrate the ESA has achieved one of its core purposes—halting the loss of species. We will not attempt to catalog them here, but numerous individual examples provide further support for this conclusion. Well known species like the California condor ( Gymnogyps californianus ), black-footed ferret ( Mustela nigripes ) and Hawaiian monk seal ( Neomonachus schauinslandi ), as well as lesser known species like the yellowfin madtom ( Noturus flavipinnis ), are but a few of the species that likely would have been lost were it not for the ESA.

The madtom is a case in point. Wrongly presumed extinct when described in 1969, individual madtom were found in the Powell River in Tennessee and Copper Creek in Virginia and the species was protected under the ESA in 1977 ( U.S. Fish and Wildlife Service, 1977 ). Following protection, federal and state officials worked with a non-governmental organization, Conservation Fisheries Inc., to discover additional populations and repatriate the species to rivers and streams in its historic range and there are now populations of the yellowfin madtom in three different watersheds ( U.S. Fish and Wildlife Service, 2012a ). The history of the ESA is replete with similar such stories.

The distribution of extinct or possibly extinct listed species largely tracks those regions with the highest rates of species endangerment, including Hawaii and the Northern Mariana Islands with 64 of the 97 extinctions or possible extinctions, and the Southeast with 18 of the extinctions or possible extinctions, mostly freshwater species. The fragility of Hawaii’s endemic fauna to introduced species and habitat destruction and high degree of species imperilment is well recognized ( Duffy & Kraus, 2006 ). Similarly, the extinction and endangerment of freshwater fauna in the southeast is well documented ( Benz & Collins, 1997 ). To avoid further extinctions, these areas should be priorities for increased funding and effort.

Protection under the ESA came too late for the 71 species last seen prior to listing. It’s possible that some of these species survived undetected following listing, but we find this unlikely for most if not all of the species. It is very difficult to document extinction, but all of the species were the subject of survey both before and after listing, which is described in the listing rules and subsequent status surveys. In addition, the 71 species were last seen an average of 24 years prior to listing, providing a long window for detection prior to listing. If some of these species did survive after listing it was likely at very low numbers, such that recovery would have been difficult at best.

That these 71 species were lost before protections were applied clearly highlights the need to move quickly to protect species. Indeed, Suckling, Slack & Nowicki (2004) identified 42 species that went extinct while under consideration for protection. Since that analysis was completed, the U.S. Fish and Wildlife Service has determined five additional species did not qualify for protection because they were extinct, including the Tacoma pocket gopher ( Thomomys mazama tacomensis ), Tatum Cave beetle ( Pseudanophthalmus parvus ), Stephan’s riffle beetle ( Heterelmis stephani), beaverpond marstonia ( Marstonia castor ) and Ozark pyrg ( Marstonia ozarkensis ), meaning there are now 47 species that have gone extinct waiting for protection ( U.S. Fish and Wildlife Service, 2012b , 2016 , 2017 , 2018a ).

The U.S. Fish and Wildlife Service currently faces a backlog of more than 500 species that have been determined to potentially warrant protection, but which await a decision ( U.S. Fish and Wildlife Service, 2018b ). Under the ESA, decisions about protection for species are supposed to take 2 years, but on average it has taken the Fish and Wildlife Service 12 years ( Puckett, Kesler & Greenwald, 2016 ). Such lengthy wait times are certain to result in loss of further species and run counter to the purpose of the statute. This problem can be addressed by streamlining the Service’s process for listing species, which has become increasingly cumbersome, and by increasing funding for the listing program. For every species listed, the Service’s process includes review by upward of 20 people, including numerous individuals who have no specific knowledge of the species and in a number of cases are political appointees. We instead recommend that the Service adopt a process similar to scientific peer review, involving review by two to three qualified individuals.

The loss of 26 species after they were protected is indicative of conservation failure. This failure, however, in most cases cannot be wholly attributed to the ESA because most of these species were reduced to very low numbers by the time they were protected, making recovery difficult to impossible. Of the 19 species we could find an abundance estimate for at the time of listing, 13 had an estimated population fewer than 100 with eight having fewer than 10 individuals. Of the six other species, two Hawaiian birds, Oahu creeper ( Paroreomyza maculate ) and ‘O’u ( Psittirostra psittacea ) had estimated populations in the hundreds, but this was based on sightings of single individuals. Given the lack of further sightings and the presence of disease carrying mosquitoes throughout their habitat, these estimates were likely optimistic. The other four species, the dusky seaside sparrow ( Ammodramus maritimus nigrescens ), Morro Bay kangaroo rat ( Dipodomys heermanni morroensis ), pamakani ( Tetramolopium capillare ) and Curtis’ pearlymussel ( Epioblasma florentina curtisii ), had populations at the time of listing ranging from 100 to 3,000 individuals, but sufficient action was not taken to save them, making them true conservation failures.

At some level, all of the 97 ESA listed species that we identified as possibly extinct or extinct are conservation failures. For 42 of these species, the law itself was too late because they were last seen before the ESA was passed in 1973. But for others, there may have been time and we did not act quickly enough or dedicate sufficient resources to saving them. There are many examples of species both in the U.S. and internationally that have been successfully recovered even after dropping to very small numbers, but this can only occur with fast, effective action, resources and in many cases luck. The Mauritius kestrel ( Falco punctatus) , for example, was brought back from just two pairs ( Cade & Jones, 1993 ) and the Hawaiian plant extinction prevention program, which focuses on saving plants with fewer than 50 individuals, has rediscovered many species believed extinct, brought 177 species into cultivation, constructed fences to protect species from non-native predators and reintroduced many species into the wild ( Wood, 2012 , http://www.pepphi.org/ ).

The failure to provide sufficient resources for conservation of listed species, however, continues to the present. As many as 27 species of Oahu tree snail ( achatinella spp. ) are extinct or possibly extinct, yet expenditures for the species that still survive are inadequate to support minimal survey and captive propagation efforts. Likewise, the Hawaiian plant extinction prevention program, which has been so effective in saving species on the brink of extinction, is facing a budget cut of roughly 70% in 2019 ( http://www.pepphi.org/ ), which very likely could mean the extinction of dozens of plants that otherwise could be saved. Overall, Greenwald et al. (2016) estimate current recovery funding is roughly 3% of estimated recovery costs from federal recovery plans. We can save species from extinction, but it must be more of a priority for federal spending. Nevertheless, despite funding shortfalls and the tragedy of these species having gone extinct, the ESA has succeeded in preventing the extinction of the vast majority of listed species and in this regard is a success.

Management implications

Of the 97 species we identified as extinct or potentially extinct, only 11 have been delisted for extinction. Another 11 have been recommended for delisting due to extinction. The San Marcos gambusia ( Gambusia georgei ) could also be delisted since there is very little hope it survives. For the other 74 possibly extinct species, we recommend retaining protections in the hope that some will be rediscovered and because there is little cost in retaining listing.

Supplemental Information

Supplemental information 1.

Extinct or possibly extinct species broken out by whether last seen before or after protection was enacted, including relevant source data and literature cited.

Funding Statement

The authors received no funding for this work.

Additional Information and Declarations

All authors are employed by the Center for Biological Diversity which works to protect endangered species and their habitats.

Noah Greenwald conceived and designed the experiments, performed the experiments, analyzed the data, prepared figures and/or tables, authored or reviewed drafts of the paper, approved the final draft.

Kieran F. Suckling conceived and designed the experiments, performed the experiments, analyzed the data, authored or reviewed drafts of the paper, approved the final draft.

Brett Hartl conceived and designed the experiments, performed the experiments, analyzed the data, authored or reviewed drafts of the paper, approved the final draft.

Loyal A. Mehrhoff conceived and designed the experiments, performed the experiments, analyzed the data, authored or reviewed drafts of the paper, approved the final draft.

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Research Article

Comprehensive approaches for assessing extinction risk of endangered tropical pitcher plant Nepenthes talangensis

Roles Conceptualization, Data curation, Formal analysis, Funding acquisition, Investigation, Methodology, Project administration, Resources, Software, Supervision, Validation, Visualization, Writing – original draft, Writing – review & editing

* E-mail: [email protected]

Affiliation Research Center for Plant Conservation, Botanic Gardens, and Forestry–National Research and Innovation Agency (BRIN), Bogor, Indonesia

Roles Conceptualization, Resources, Supervision, Writing – original draft, Writing – review & editing

Roles Conceptualization, Investigation, Resources, Supervision, Writing – original draft, Writing – review & editing

Roles Data curation, Resources, Writing – original draft, Writing – review & editing

Roles Data curation, Formal analysis, Software, Writing – original draft, Writing – review & editing

Roles Project administration, Resources, Writing – original draft, Writing – review & editing

Roles Investigation, Resources, Writing – original draft, Writing – review & editing

Roles Data curation, Investigation, Resources, Supervision, Writing – original draft, Writing – review & editing

Affiliation Research Center for Biosystematics and Evolution–National Research and Innovation Agency (BRIN), Bogor, Indonesia

Roles Investigation, Validation, Writing – original draft, Writing – review & editing

Roles Investigation, Supervision, Writing – original draft, Writing – review & editing

Affiliation Research Center for Ecology and Ethnobiology–National Research and Innovation Agency (BRIN), Bogor, Indonesia

Roles Formal analysis, Methodology, Software, Visualization, Writing – original draft, Writing – review & editing

Affiliation Research Center for Limnology and Water Resources–National Research and Innovation Agency (BRIN), Bogor, Indonesia

Affiliation Research Center for Geological Resources–National Research and Innovation Agency (BRIN), Bogor, Indonesia

Affiliation Faculty of Science and Technology, UIN Sunan Gunung Djati Bandung, Bandung, Indonesia

•  [ ... ],

Roles Methodology, Software, Validation, Writing – original draft, Writing – review & editing

Affiliation School of Forest, Fisheries, and Geomatics Sciences, University of Florida, Gainesville, FL United States of America

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• Angga Yudaputra, 
• Inggit Puji Astuti, 
• Tri Handayani, 
• Hartutiningsih Siregar, 
• Iyan Robiansyah, 
• Sri Wahyuni, 
• Arief Noor Rachmadiyanto, 
• Danang Wahyu Purnomo, 
• Vandra Kurniawan, 

• Published: August 7, 2023
• https://doi.org/10.1371/journal.pone.0289722
• Peer Review
• Reader Comments

It has been 23 years since the conservation status of highland tropical pitcher plant Nepenthes talangensis was assessed in 2000. A number of existing threats (anthropogenic and environmental) may be increasing the risk of extinction for the species. A better understanding of the ecology and conservation needs of the species is required to manage the wild populations. Specifically, better information related to population distributions, ecological requirements, priority conservation areas, the impact of future climate on suitable habitat, and current population structure is needed to properly assess extinction risks. A better understanding of the requirements of the species in its natural habitat would benefit for successfully securing the species at Botanic Gardens. We have identified 14 new occurrence records of N . talangensis in Mount Talang. Study on the ecological requirement using Random Forest (RF) and Artificial Neural Network (ANN) suggested that elevation, canopy cover, soil pH, and slope are four important variables. The population of N . talangensis was dominated by juvenile and mature (sterile) individuals, we found only a few mature males (7 individuals) and females (4 individuals) in the sampled areas. Our modelling of current conditions predicted that there were 1,076 ha of suitable habitat to very highly suitable habitat in Mount Talang, which is 14.7% of the total area. Those predicted habitats ranged in elevation from 1,740–2,558 m. Suitable habitat in 2100 was predicted to decrease in extent and be at higher elevation in the less extreme climate change scenario (SSP 1–2.6) and extreme climate change scenario (SSP 5–8.5). We projected larger habitat loss in the SSP 5–8.5 compared to the SSP 1–2.6 climate change scenario.. We proposed the category CR B1ab(iii,v), C2a(ii) as the new conservation status of N . talangensis . The status is a higher category of threat compared to the current status of the species (EN C2b, ver 2.3). Nepenthes talangensis seedlings and cuttings established in a Botanic Garden have relatively high survival rate at about 83.4%. Sixty percent of the seeds germinated in growth media successfully grew to become seedlings.

Citation: Yudaputra A, Astuti IP, Handayani T, Siregar H, Robiansyah I, Wahyuni S, et al. (2023) Comprehensive approaches for assessing extinction risk of endangered tropical pitcher plant Nepenthes talangensis . PLoS ONE 18(8): e0289722. https://doi.org/10.1371/journal.pone.0289722

Editor: Andrea Mastinu, University of Brescia: Universita degli Studi di Brescia, ITALY

Received: April 10, 2023; Accepted: July 25, 2023; Published: August 7, 2023

Copyright: © 2023 Yudaputra et al. This is an open access article distributed under the terms of the Creative Commons Attribution License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: All relevant data are within the manuscript and its Supporting Information files.

Funding: This study was funded by Nagao Natural Environment Foundation (NEF). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The URL: https://www.nagaofoundation.or.jp/e/

Competing interests: The authors have declared that no competing interests exist.

Introduction

Nepenthes talangensis Nerz & Wistuba is an endemic pitcher plant with a restricted distribution range, only found in Mount Talang, West Sumatra [ 1 ]. It is a highland pitcher plant and grows in mossy forests and upper montane forests at 1,800 to 2,500 m elevation near the summit of Mount Talang [ 2 , 3 ]. It commonly grows as rosettes and climbs in low shrubs [ 4 ]. In an early study, Bunnemeijer’s specimen collection from Mount Talang was determined to be N . bongso [ 5 ]. Nepenthes talangensis has been thought to be closely related to N . bongso [ 6 , 7 ]. However, recent studies confirmed that both are distinct species based on morphological characters [ 3 , 8 ]. Nepenthes talangenis has two types of pitchers (lower pitcher and upper pitcher). These two types of pitchers have different colours and shapes. The upper pitcher is relatively slender and longer than lower pitcher [ 8 ]. Nepenthes talangensis has a relatively large peristome that maximizes the effective trapping surface [ 9 ].

According to the last assessment [ 1 ], it is classified as endangered with very limited information. It has been about 23 years since the last assessment so there may be significant changes in populations or species distribution. Some disturbances may lead the decline of its population in the wild, for instance, habitat fragmentation due to the existence of hiking trails and illegal harvesting by plant enthusiasts [ 10 ]. Past studies have characterized the taxonomic, systematic, physiological, and ecological characteristics of the species [ 4 , 8 , 11 – 13 ].

Due to continuing threats to the population and habitat, and also the limited available information about N . talangensis , it is important to carry out a comprehensive study of the ecological requirements, current population status, and in-situ and ex-situ conservation strategies. In order to address these problems, our study includes the following objectives: 1). New occurrence data and ecological requirement modelling, 2). Estimating the current population size structure, 3). Prioritizing conservation areas, 4). Recognizing the trend of future suitable habitats under future climate scenarios, 5). Assessing the conservation status based on IUCN Red List, and 6). Understanding the survival rate of the species during securing efforts in a Botanic Garden.

Materials and methods

Surveys of the endangered tropical pitcher plant Nepenthes talangensis were carried out in Mount Talang, an active stratovolcano located in Solok, West Sumatra. It has two crater lakes with a summit of 2,597 m [ 14 , 15 ]. The lowest daily average low temperature of Mount Talang is 18°C, and the highest temperature hits to 26°C [ 16 ]. This area receives an average rainfall of 3,000 mm/year and has steep slopes of more than 45% [ 17 ]. The study area covers around 7,345.8 ha.

Nepenthes talangensis surveys and characterizing ecological requirements

The data collection was carried out by surveying the accessible locations on Mount Talang. These locations were accessed from three different hiking trails. The ecological and population data within a 20 x 20 m 2 plot size were measured at each location where the species was present. The coordinate points where species presence were recorded relative to the nearest hiking trail. The Quantum GIS Desktop 3.18.1 software was used to map the occurrence records [ 18 ].

Physical environment variables included elevation, slope, aspect, soil moisture, soil pH, litter thickness, and canopy cover. The relationships of these environmental variables to habitat quality were evaluated using Random Forest (RF) [ 19 ] and Artificial Neural Network (ANN) [ 20 ] models. The analyses used R packages “randomForest” [ 21 ] and “neuralnet” [ 22 ]. R studio version 1.2.5042 was used to run the models [ 23 ]. Soil samples were analysed to quantify soil chemical composition, soil pH, base saturation, and cation exchange capacity. Four “R packages” were used to do PCA analysis, those were “devtools” [ 24 ], “doParallels” [ 25 ], “ggplot2” [ 26 ], and “ggbiplot” [ 27 ]. PCA was used to show a clustering of samples based on their similarity. There were two PCA axes: PCA 1 (x-axis) was the first principal direction and PCA 2 (y-axis) was the second most important direction. Plant association were defined as the plant species found inside the plots. A species composition similarity index was calculated using the jaccard index [ 28 , 29 ] and visualisation was presented using a ‘heat map’ [ 30 ].

Population size structure

Population structure data was derived by grouping the individuals into: seedling, juvenile, mature sterile, mature (female) and mature (male). The population size data were obtained by counting all individuals within each plot. The life stages of N . talangensis was categorized into three classes (seedlings, juveniles and mature plants) based on their stem lengths and reproductive status. Seedlings had stem lengths < 10 cm, juveniles were 10–20 cm, mature sterile were > 20 cm (without inflorescences), mature male were > 20 cm (with inflorescences), and mature female were > 20 cm (with inflorescences) [ 31 ].

Prioritizing conservation areas

In order to develop a tool for prioritizing conservation areas for Nepenthes talangenis , spatial modelling incorporating habitat characteristics where the species was present and occurrence records were used as inputs to the model. Climatic data with a 30 arc second (∼1 km) spatial resolution was extracted from WorldClim version 2.1 climate data for 1970–2000. These variables including annual mean temperature, precipitation of wettest month and precipitation of driest month [ 32 ]. Four soil variables include soil type, soil pH, soil organic carbon, and cation exchange capacity with a 250 m spatial resolution were derived from SoilGrids—global gridded soil information [ 33 ]. Land cover was also applied as a predictor of habitat suitability. Land cover data were derived from Peta Rupabumi Digital Indonesia [ 34 ]. Topography data was extracted from NASA Shuttle Radar Topography Mission (SRTM), it was available at a 0.27-arc second resolution [ 35 ]. These environmental layers and occurrence records were used as inputs to the model. An ensemble model [ 36 ] constructed by combining the prediction of Random Forest (RF) and Support Vector Machine (SVM), was used to predict the suitable habitat of the species. The R “dismo” and R “sdm” package were used to generate the model prediction [ 37 ]. Two evaluation metrics: Area Under Curve (AUC) and True Skill Statistics (TSS) were used to validate the performance of model prediction. The value of AUC in range 0.9–1 (excellent), 0.8–0.9 (good), 0.7–0.8 (fair), 0.6–0.7 (poor), and 0.5–0.6 (fail) [ 38 ]. Whereas, TSS statistics can be interpreted as the following: values < 0.4 were poor, 0.4–0.8 useful, and > 0.8 good to excellent [ 39 ].

Finally, the result of the prediction map was further analysed to identify high priority conservation areas. The predictive map was classified into five classes: unsuitable habitat (0–0.2), barely suitable habitat (0.2–0.4), suitable habitat (0.4–0.6), highly suitable habitat (0.6–0.7), and most suitable habitat (0.7–1.0) [ 40 , 41 ]. After grouping the potential habitats, the predicted area and elevation were calculated for each class of potential habitat.

Future suitable areas under future climate scenario

Future climate scenario variables were derived from WorldClim version 2.1 [ 32 ]. Global Climate Model (GCM) MIROC 6 with Shared Socioeconomic Pathways (SSP 1–2.6 and SSP 5–8.5) was used to model future habitat suitability for N . talangensis . The future climate data was available at a 30 arc second (∼1 km) spatial resolution. These future climate variables were combined with other variables (topography, soil, land cover) that were used as inputs of the model. The predictive map represented the future suitable distribution of N . talangensis in the year 2100.

Conservation status assessment

We assessed the extinction risk of Nepenthes talangenis using the IUCN Red List categories and criteria version 3.1 [ 42 ]. Due to data availability constraints, we only used criteria B (geographic range), C (small population size and decline), and D (small and restricted population) to assess and classify the species into one of the following categories: Critically Endangered (CR), Endangered (EN), Vulnerable (VU), Near Threatened (NT), and Least Concern (LC). The extent of occurrence (EOO) and area of occupancy (AOO) of the species used in criterion B were calculated using Geospatial Conservation Assessment Tool (GeoCAT) [ 43 ], whilst the population size value used in criteria C and D was estimated based on the total number of mature individuals.

Securing individuals at Botanic Gardens

Several individuals of N . talangensis were collected from Mount Talang. Seedlings, cuttings and fruits were taken from the natural habitat in order to preserve the species. Three types of growth media (roasted husks, moss, and mixed media consist of cocopeat + roasted husks + moss) were used to test establishment. Seedlings and cuttings were planted in the growth media, while seeds were grown in several combinations of growth media through a plant tissue culture technique. The survival rates of seedlings and cuttings were observed during establishment periods in the Cibodas Botanic Gardens. The germination of seeds and establishment of seedling and cuttings were conducted for 0–20 weeks of observation.

We found Nepenthes talangensis in 14 previously undocumented locations during our field surveys in Mount Talang ( Fig 1 ). Those locations ranged from 1,819 to 2,489 m elevation. Machine learning models may use many inputs with complex relationships to each other and with the model outputs. A variety of techniques can be used to evaluate the relative importance of the inputs. The Mean Decrease Gini metric integrates the variable importance estimates over multiple trees with multiple splits. In the Random Forest (RF) model elevation was associated with the highest value (most important) of the model Mean Decrease Gini (4.673) and litter thickness had the lowest value (0). The four variables most important for predicting habitat suitability are elevation, canopy cover, slope and soil pH ( Fig 2A ). In the Artificial Neural Network (ANN) model elevation had the highest importance value (<30) and aspect was the lowest value (less than 5). There were four variables in the ANN (elevation, canopy cover, soil pH, and soil moisture) that had high importance values. Elevation, soil moisture, slope and litter thickness were positively associated with the species. Three input variables (canopy cover, soil pH, and aspect) have negative importance values which means those variables negatively influence the species ( Fig 2B ). The RF has a model accuracy of 0.877 and the ANN has a model accuracy of 0.820. Both the RF and ANN found elevation, canopy cover and soil pH to be the most important variables in driving habitat suitability ( Fig 2A and 2b ).

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https://doi.org/10.1371/journal.pone.0289722.g001

The importance variables that influence the occurrence of Nepenthes talangensis : a) Random Forest (RF), b). Artificial Neural Network (ANN).

https://doi.org/10.1371/journal.pone.0289722.g002

The first principal component explained 76.4% of the variability in the data. Variable correlation plots graphically depict the relationship between all of the variables. Variables were grouped together based on their correlations. Several variables (AI 3+ , N total, CEC, K 2 O potential, C-organic, CEC, P 2 O 5 potential, Na 2+ , H + ) were positively correlated, while other variables (C/N ratio, pH H 2 O, pH KCL) were negatively correlated ( Fig 3A and 3B ).

Principal Component Analysis (PCA) of soil components in different locations: a). PCA Biplot, b) PCA circle plot.

https://doi.org/10.1371/journal.pone.0289722.g003

Species composition is potentially an important attribute of plant communities, but high variability and diversity can make it difficult to interpret. A heat map of species composition similarity helps to understand the ecological patterns. This heat map has an X axis representing plots where the species was present and the Y axis represents the plant species present inside the plots. In the heat map visualization ( Fig 4 ), there were three distinct groups. A darker grid colour indicates a high abundance, and a brighter grid colour indicates a low abundance. Plots 11, 12, 13, and 14 have similar species compositions, dominated by Medinilla , Cyathea , Elaeocoarpus and mosses, plots 1, 2, 3, 4, 5, and 6 were dominated by Vaccinium , Pandanus , and Anaphalis , and plots 7, 8, 9, and 10 were characterized by Parkia , Lasianthus , Ardisia , Passiflora and Lithocarpus ( Fig 4 ). An average Jaccard similarity index among plots 11, 12, 13, and 14 was > 0.8, for plots 1, 2, 3, 4, 5, and plot 6 was > 0.6, and for plots 7, 8, 9, and plot 10 was > 0.7.

https://doi.org/10.1371/journal.pone.0289722.g004

The juvenile growth stage has the largest number individuals (78 individuals), followed by mature (69 individuals) and seedlings (54 individuals). The largest size class of seedlings was stem lengths from 2 to 4 cm ( Fig 5A ). Individuals with stem lengths from 16 to18 cm dominated the juvenile growth stage ( Fig 5B ) and individuals with stem lengths from 20 to 50 cm (the smallest mature size class) were more numerous than other mature size classes ( Fig 5C ).

Population size and structure of Nepenthes talangensis at different growth stage: a). Seedling individuals, b). Juvenile individuals, c). Mature individuals.

https://doi.org/10.1371/journal.pone.0289722.g005

Visualization of potential locations with suitable habitat for protection, and perhaps establishment of new populations of an endangered species can be an effective aid for conservation planning. The model predicted relative habitat suitability (in a range of 0.0 to 1.0) that we grouped into 5 categories. Unsuitable habitat had values of 0–0.2, barely suitable habitat had values of 0.2–0.4 suitable habitat had a range of 0.4–0.6, highly suitable habitat had values of 0.6–0.7, and the most suitable predicted habitat ranged from 0.7–1.0 ( Fig 6 ). The area classified into the unsuitable habitat category had the largest area (5,381.3 ha or 73%) at the elevation range from 812 to 1,605 m, barely suitable habitat (0.2–0.4) included an area of 888 ha (12.1%) from 1,605 to 1,740 m elevation, suitable habitat (0.4–0.6) had an area of 496.4 ha (6.8%) from 1,740 to 1,917 m, highly suitable habitat (0.6–0.7) had the smallest area of 212.4 ha (2.9%) from 1,917 to 2,080 m, and the most suitable habitat class (0.7–1.0) had an area of 367.7 ha (5%) from 2,080–2,558 m ( Fig 7 ). This predictive model is a relatively good predictor of habitat quality with an AUC of 0.97 and a TSS of 0.95. Values of AUC and TSS greater than 0.90, is typical of models that effectively distinguish between presence and absence in observed locations.

https://doi.org/10.1371/journal.pone.0289722.g006

https://doi.org/10.1371/journal.pone.0289722.g007

Climate variables are important predictors of habitat suitability, allowing predictions of change in habitat suitability associated with climate change scenarios. Predictive future habitat quality of N . talangensis using the SSP 1–2.6 scenario showed that class (0–0.2) covered 6,191.62 ha (80.4%) at the elevation range between 812 to 1,820 m, class (0.2–0.4) had an area of 552.69 ha (7.2%) at 1,820 to 2,090 m elevation, class (0.4–0.6) had an area of 351.02 ha (4.6%) at 2,090 to 2,315 m, class (0.6–0.7) had an area 151.29 ha (2%) at 2,315 to 2,356 m, and class (0.7–1.0) had an area of 456.41 ha (5.9%) at 2,356–2,558 m ( Fig 8 ). The predicted future suitable habitat of N . talangensis using the SSP 5–8.5 scenario showed that class (0–0.2) covered 6,500.98 ha (84.6%) at an elevation range between 812 to 1,914 m, class (0.2–0.4) had an area of 501.61 ha (6.5%) at 1,914 to 2,051 m elevation, class (0.4–0.6) had an area of 364.01 ha (4.7%) at 2,051 to 2,253 m, class (0.6–0.7) had an area 170.84 ha (2.2%) at 2,253 to 2,400 m, and class (0.7–1.0) had an area 149.05 ha (1.9%) at 2,400–2,558 m ( Fig 9 ).

https://doi.org/10.1371/journal.pone.0289722.g008

https://doi.org/10.1371/journal.pone.0289722.g009

GeoCAT showed that the species had an EOO and AOO of 12 km 2 . Since the species had an EOO<100 km 2 , in a single location, and inferred to experience continuing decline in area, extent and quality of habitat as well as in the number of mature individuals, under criterion B it could be categorized as CR B1ab(iii,v). Our surveys located a total of 69 mature individuals of the species. Therefore, the species qualified for the category of CR under criterion C2a(ii), i.e. number of mature individuals<250, inferred to experience continuing decline, and all the mature individuals were in one population. For criterion D, the species could be assessed as EN since its number of mature individuals was higher than 50 but less than 250.

Securing Nepenthes talangensis in Botanic Gardens

Only a few seedlings and cuttings were taken from Mount Talang. From six seedlings that were grown in the greenhouse, five remained alive during the five months of observation ( Fig 10 ). From five cuttings, only four were still alive as characterised by some new leaf emergence. During the five months of the germination experiment, there were 20 seedlings that germinated from the seeds and 17 of those developed a pitcher in the roasted husks growth media, 18 seedlings (14 with a pitcher) in the moss media, 13 seedlings (seven with a pitcher) in the cocopeat media, and 18 seedlings (14 with a pitcher) in the mixed media.

https://doi.org/10.1371/journal.pone.0289722.g010

Nepenthes talangensis is a rare species with only a few occurrence records found during the field surveys, mostly in upper elevations near the summit of Mount Talang. Some locations could not be sampled due to the topography. The environmental characteristics were measured or determined for each presence location. Characterizing the habitat variables at presence locations is valuable in terms of understanding the ecological requirements of N . talangensis . Both machine learning models Random Forest (RF) and Artificial Neural Network (ANN)) predict that similar environmental variables are associated with presence in the wild. These variables are elevation, canopy cover, slope and soil pH. Elevation is identified as the most important variable determining the species presence in the wild. In the field surveys, the species is seen from 1,819 to 2,489 m elevation. It is found in three different areas: upper montane forest from 1,819 m to 2,360 m, mossy forest with 2,489 m elevation at the summit of Mount Talang, and steep hillsides at 2,239 to 2,288 m elevation near the summit. High elevation is characterized by severe environmental conditions that drastically change diurnally [ 44 ]. Temperature tends to decrease 0.5 °C per 100 m of increasing elevation [ 45 ] and rainfall tends to decrease upslope in many tropical mountains [ 46 ]. These conditions can be less favourable for some plants [ 47 ]. However, N . talangensis is able to adapt and survive in the higher elevations. A previous study found that highland Nepenthes have different anatomical structures (thicker leaf, larger hypodermis, thicker cuticle, smaller leaf) compared to lowland Nepenthes associated with the level of environmental variability [ 48 ]. Canopy cover is another important variable affecting the species, the locations where the species was found have canopy cover between 0 and 67.68%. The locations on exposed steep slopes near the summit have 0–5% canopy cover, locations on sunny areas in mossy forests have 42.05–54.16% canopy cover, and locations in upper montane forests have 53.5–67.68% canopy cover. Some individuals grow well on exposed areas on steep slopes near mountain summits by climbing on short vegetation or growing on the ground. Even though some individuals have a relatively short appearance, they often have many pitchers. The pitcher has a distinct colour with the mouth of pitcher typically coloured red to darker red. Our results are consistent with a previous study that found that N . mirabilis produces numerous pitchers on exposed habitat in the York Peninsula in Australia [ 49 ].

In mossy forests, some individuals can be found in the open short vegetation and some of them are epiphytes climbing on tall trees. The branches and trunks of trees in mossy forests are covered with mosses. Those individuals also have numerous pitchers, but the mouth of pitcher tends to have a brighter yellow colour. Individuals growing in upper montane forests tend to have a denser canopy cover, some individuals climb tall trees with a length of more than 3 m. It seems that the individuals climbing the tall trees to gain more sunlight. The individuals growing at the upper montane region have numerous and larger pitchers, but some of them appear dry and have died. Few dead pitchers are found fallen to the ground from tall canopies. The denser the canopy, the higher the species climbs up the standing trees. Canopy cover closely correlates to the amount of light received by the plants and light intensity affects the growth rate and pitcher production in Nepenthes [ 50 ]. Commonly, Nepenthes requires full sunlight to grow well, and fails to produce flowers under heavy dense canopies [ 51 ]. Slope is another environmental variable affecting the distribution of N . talangensis . Individuals are typically found in steep slopes (30–45%). The species can grow well from mid slope to hill slope. Although mid and hill slope usually have lower soil moisture compared to bottom slope, those locations are suitable for N . talangensis . In these cases, the soil surface is covered by mosses with soils losing less moisture due to evaporation. Meanwhile, slope in mossy forests and upper montane forests is varied from 0–25%. Locations with N . talangensis present have soil pH values ranging from 5.4 to 6.4, categorized as acidic soil. This finding similar to several previous studies that found that Nepenthes mirabilis grows well in soil pH ranging between 5 and 6.1 [ 52 ], Nepenthes ( Nepenthes ampullaria , Nepenthes gracilis and Nepenthes rafflesiana ) grow in soil pH values ranging from 3.74 to 4.21 [ 53 ], Nepenthes gracilis grows in soil pH values of 4.17 to 5.56 [ 54 ], and three other Nepenthes species ( N . gracilis , N . rafflesiana and N . ampularia ) are found in very acidic soil with pH values of 3.60 to 3.95 [ 55 ]. The majority of carnivorous plants are found in sites with poor nutrients, and sunny and moist conditions during the growing season [ 56 , 57 ].

The surveyed plots can be grouped into three different locations (steep hills near the summit, mossy forests near the mountain summit, and upper montane forests). These locations have different plant compositions where N . talangensis are found. The locations on steep slopes are dominated by Pandanus sp., mosses that covering the hill’s surface, N . inermis grows side by side with N . talangensis and short stature vegetation ( Vaccinium and Rhododendron ). In mossy forest is dominated by Moss, Medinilla , Cyathea , and N . gymnamphora . Locations in upper montane forests are dominated by tall vegetation ( Memecylon , Lithocarpus ) and N . bongso grows close to N . talangensis . Several previous studies reported that N . mirabilis and N . rafflesiana are found in Padang Alan Forest dominated by Shorea albida and Padang Kerumutan Forest dominated by Combretocarpus rotundatus [ 51 ]. Nepenthes reinwardtiana grows epiphytically on Dipterocarpus oblongifolius trees [ 51 ]. In addition, N . hookeriana is found climbing among Gleichenia bushes [ 58 ]. It is likely Nepenthes tends to use any standing trees to climb if it grows under dense canopy, but it creeps on the soil surface and climbs short vegetation in sunny and exposed areas.

Soil fertility on the steep slopes near the summit is relatively low based on N total, P 2 O 5 available, K 2 O potential and CEC measurements. The low fertility soils generally have a large loamy sand component. The sand fraction has poor physical properties because the particles are easily separated due to weak cohesive forces between the particles [ 59 ], so the ability to bind water [ 60 ] and essential elements becomes low [ 61 ]. The low cohesive forces in the sand fraction will also increase the rate of evaporation, thus accelerating the loss of water and nutrients [ 62 ]. However, the organic carbon content in the locations where N . talangensis grows on rocky hills is relatively high due to the large amount of litter that has completely decomposed. So even though organic carbon is high, litter nutrients only slowly available to be absorbed by plants. Nepenthes is able to live in conditions of low soil fertility such as on rocky slopes because these plants are adapted to sites with low nitrogen availability [ 3 , 63 , 64 ]. The soil surface in mossy forests is dominated by moss litter. This litter is characterized by a very high organic C content (48.03%), so N . talangensis in this location does not grow on true soil but can grow on the litter resulting from the decomposition of moss biomass. The quality of the litter as for growth at this location can be categorized as very high with respect to the total N, available P 2 O 5 , potential K 2 O and CEC. The soil pH surrounding of moss surface at this location is very acidic, but the species is tolerant to these conditions. Nepenthes spectabilis and N . tobaica are also able to grow in soil with a high humus content or under large tree stands [ 65 ]. Soil fertility at the upper montane forest is almost the same as the mossy forest. Nepenthes has a very wide adaptability, from soils with low to very high fertility conditions. It grows on soil textures predominately sandy to soils dominated by litter or mosses.

Knowing the population size structure of a certain plant can help to better understand the population stability and disturbance history [ 66 ]. According to our field surveys, the population is dominated by juvenile individuals, followed by mature sterile (without inflorescence) and seedlings. Only a few mature males and females were found during the surveys. The largest populations are found in the upper montane forest, followed by the mossy forest and in open areas on steep slopes near the summit. Very few mature fertile individuals (female and male) and small population sizes implies that these populations are at risk of local extinction. Although the species is able to produce in numerous seeds and grow in several locations in Mount Talang (upper montane forest, mossy forest, and open areas at steep hill near the summit), the population and locations where the species presence need to be protected.

Determining the priority of conservation areas becomes important to protect the threatened and endemic plant species. In order to set a priority of conservation areas, Species Distribution Models (SDMs) have been widely used to predict the species potential range by relating knowing occurrence to environmental variables where the species is present. Even though SDM models have some problems related to uncertainty and error [ 67 , 68 ] due to sampling bias and data sparseness [ 69 ], the use of SDM in conservation planning becomes a useful tool to select high priority areas for protection [ 70 ]. An ensemble model by combining multiple algorithms is widely used to get better predictive performance, previous study stated that ensemble model performs better in predicting suitable areas of endangered giant flower Amorphophallus titanum [ 71 ]. The ensemble model predicts three suitable classes (suitable, highly suitable and very highly suitable) that are concentrated in the upper montane forest to the summit of Mount Talang. The proposed conservation areas cover 14.9% of total areas of Mount Talang. It is smaller than the unsuitable area of the species (85.1%). The predicted suitable areas can be used as a basis for selecting priority areas that should be protected. The three classes of suitable habitat (suitable, highly suitable and very highly suitable) are located from 1,740 to 2,558 m elevation. According to the actual surveys, the species is observed at 1,819 to 2,489 m elevation. There are still many areas that have not been surveyed, making it difficult to fully evaluate extinction risk. These findings are in accordance with a previous study that found that the species grows in mossy forest and upper montane forest at 1800–2500 m elevation near the summit of mountains [ 2 , 3 ].

Global and regional climates are expected to change dramatically during the 21 st century, [ 72 ]. This environmental alteration impacts ecophysiology, distribution, regeneration biology and biotic interaction. The response of plants to environmental changes depends upon functional traits, taxonomy, and life history [ 73 ]. Predicted future suitable habitat areas of N . talangensis exhibit a small decrease in 2100 using SSP 1–2.6 (a more benign scenario of climate change) and a significant decrease using SSP 5–8.5 (a worst case scenario). The future suitable areas of the species are predicted to shift uphill closer to the summit of the mountain. This is consistent with a previous study that found the climatically-suitable habitat of highland species Nepenthes tentaculata is predicted to significantly decrease in 2100 [ 74 ]. Montane endemic Nepenthes is seriously at risk due to anthropogenic climate change, even a slight change of temperature and precipitation could be quite enough to threaten the species of Nepenthes . Climate change could potentially reduce gene flow between the isolated sub-populations, perhaps increasing extinction risks. The best habitat will move upslope isolate sub-population. This pattern has happened with N . lowii and N . ephippiata Danser. These species were previously found on Mount Kinabalu and Mount Tambuyukon, but now these are only found in a restricted area of Mount Trusmadi, 55 km to the south [ 75 ]. Although some highland Nepenthes are predicted to undergo a decrease of suitable areas in the future climate projections [ 74 , 76 ], some species may be able to produce a specific metabolite in order to adapt and tolerate to heat and cold stress [ 77 ].

Our assessment showed that N . talangensis is qualified for CR under criteria B1ab(iii,v), C2a(ii), and EN under criterion D. Since the species should be listed using the highest category of threat [ 78 ], we proposed the category CR B1ab(iii,v), C2a(ii) as the new conservation status of N . talangensis . The status has a higher category of threat compared to the current status of the species (EN C2b, ver 2.3). Therefore, N . talangensis should be considered to be facing an extremely high risk of extinction in its natural habitat.

Seedlings had relatively high survival rate during the five months of observation. The growth was characterized by emergence of new leaves and pitchers. Cuttings also had high survival rate, but the growth was relatively slower. New leaves appeared on some cuttings, but no roots were formed after a few weeks of observation. The cuttings without roots were unable to survive. Further observations are required to better understand growth and reproduction. The use of proper growth media is a critical aspect in securing the species in Botanic Gardens. Several combinations of growth media using moss, cocopeat, and roasted husk show similar numbers of seeds that completely germinating. A previous study reported that mixed media containing moss, cocopeat and roasted husk is a good media for root growth of N . gracilis . These media are capable of absorbing sufficient water, have enough Nitrogen (N) and phosphorus (P) availability, and pH in range 5.2–6.41 [ 79 ] for plant survival and growth. In terms of securing the species thorough ex-situ conservation strategies, it is necessary to consider how the number of individuals that would be taken from nature would affect the sustainability of their populations.

Conclusions

New occurrence records of Nepenthes talangensis have been identified through field surveys. Elevation, canopy cover and slope are variables that best predict suitable habitat for N . talangensis . Poor nutrient soils and acidic soils are typical in the locations where the species found. The vegetation composition of sites with N . talangensis present is highly variable. The population is dominated by juvenile and mature (sterile) individuals, only a few mature male and female are found in its natural habitat. The surveys included locations where the species is found from 1,819 to 2,489 m elevation, but ensemble modeling predicted that the suitable habitat covers 14.7% of total areas (1,076.5 ha) at 1,740 m to 2,558 m elevation nearby the summit of Mount Talang. The future suitable habitat predicted from climate change scenarios tends to be reduced and at higher elevations. We propose a new conservation status of CR B1ab(iii,v), C2a(ii) based on IUCN Red List Criteria. During attempts to establish seeds and cuttings in Botanic Gardens, some secured individuals were able to live, have a slow growth rate, and produced some new pitchers.

Supporting information

https://doi.org/10.1371/journal.pone.0289722.s001

https://doi.org/10.1371/journal.pone.0289722.s002

https://doi.org/10.1371/journal.pone.0289722.s003

Acknowledgments

We would like to thank The Head of Research Center for Plant Conservation, Botanic Gardens and Forestry (BRIN) who supporting us to conduct this study. We also thank to UPTD KPHL Solok for allowing us to conduct field surveys in Mount Talang, West Sumatra, Indonesia. We just wanted to express our appreciation for Harto, a staff of Directorate of Scientific Collection Management who helping us during fieldwork in Mount Talang.

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In vitro asymbiotic seed germination and seedling development of four endangered Ecuadorian orchids: Epidendrum Jamiesonis , Pleurothallis pulchella , Oncidium pentadactylon , and Elleanthus capitatus

• Original Article
• Published: 12 September 2024
• Volume 158 , article number  60 , ( 2024 )

Cite this article

• Nathalia Valencia-Glushchenko   ORCID: orcid.org/0000-0002-5275-6198 1 ,
• Claudia G. Oña-Arias   ORCID: orcid.org/0000-0001-7347-6032 1 ,
• Miguel Orellana 1 ,
• Mayra Ortega 1 ,
• Andrea Montero-Oleas   ORCID: orcid.org/0000-0002-4659-775X 1 &
• Maria de Lourdes Torres   ORCID: orcid.org/0000-0001-7207-4568 1  

Although Ecuador is one of the richest places in the world in terms of biodiversity of species belonging to the Orchidaceae family, some of its species are endangered. The main factors that are threatening orchid species include destruction of their habitat, inadequate management of resources, environmental contamination, and overcollection of specimens. Each orchid capsule contains thousands of seeds; however, only 2–3% germinate under natural conditions. The limited germination is attributed to factors such as the lack of seed endosperm and the need for symbiotic relationships with mycorrhizae. The in vitro orchid culture may be a strategy to achieve their efficient propagation and thus contribute to their conservation. This study reports protocols for in vitro seed germination in four species of Ecuadorian orchids: two epiphytic species, Epidendrum jamiesonis and Oncidium pentadactylon , and two terrestrials, Pleurothallis pulchella and Elleanthus capitatus . A germination percentage higher than 30% was observed in all species, which led to successful seedling development. For Epidendrum jamiesonis , effective elongation and acclimatization stages are also reported. The plants obtained from the in vitro asymbiotic culture described here could promote conservation programs and serve as a reference for the culture of other orchid species.

Key message

We report a successful in vitro seed germination protocol for four species of Ecuadorian orchids, with germination rates above 30% and successful seedling development. These results offer a valuable conservation strategy for orchid propagation in vulnerable ecosystems.

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Abbreviations

Modified Murashige and Skoog in a half of its concentration

Activated charcoal

Gibberellic acid

Modified Murashige and Skoog

Phytamax ™ Orchid Maintenance Medium

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Acknowledgements

We express our gratitude to Diana Calderon, Pamela Vega, and Paula Erazo for taking care of the orchid’s plants during the COVID-19 pandemic period. To Maria Mercedes Cobo for her support during the initial stage of the research. To Patricio Oña for his support in orchid identification and capsule collection. We express our thanks to the Colegio de Ciencias Biológicas y Ambientales (COCIBA) of the Universidad San Francisco de Quito (USFQ) for providing the necessary funds (Project ID: 7676) to carry out this project. Sample collection was performed in compliance with the research permits No 013-2018-IC-FLO-DNB/MA and Nº003-2019-IC-FLO-DPAPCH-MA issued by the Ecuadorian Ministry of Environment.

This work was supported by the Colegio de Ciencias Biológicas y Ambientales (COCIBA) of the Universidad San Francisco de Quito (USFQ) Project ID: 7676.

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All authors contributed to the study conception and design. Material preparation, data collection, and analysis were performed by Nathalia Valencia-Gluschenko and Claudia G. Oña-Arias. The draft of the manuscript was written an edited by Nathalia Valencia-Gluschenko, Claudia G. Oña-Arias, Miguel OrellanaAfrair, Mayra Ortega, Andrea Montero, and María de Lourdes Torres. All authors read and approved the final manuscript.

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Valencia-Glushchenko, N., Oña-Arias, C.G., Orellana, M. et al. In vitro asymbiotic seed germination and seedling development of four endangered Ecuadorian orchids: Epidendrum Jamiesonis , Pleurothallis pulchella , Oncidium pentadactylon , and Elleanthus capitatus . Plant Cell Tiss Organ Cult 158 , 60 (2024). https://doi.org/10.1007/s11240-024-02841-2

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Botanist Steve Perlman rappels into the Kalalau Valley, a biodiversity hotspot on the Hawaiian island of Kauai. Courtesy of Bryce Johnson/ FLUX Hawaii

Extreme Botany: The Precarious Science of Endangered Rare Plants

They don’t make the headlines the way charismatic animals such as rhinos and elephants do. But there are thousands of critically endangered plants in the world, and a determined group of botanists are ready to go to great lengths to save them.

By Janet Marinelli • October 18, 2018

To save plants that can no longer survive on their own, Steve Perlman has bushwhacked through remote valleys, dangled from helicopters, and teetered on the edge of towering sea cliffs. Watching a video of the self-described “extreme botanist” in actio­­n is not for the faint-hearted. “Each time I make this journey I’m aware that nature can turn on me,” Perlman says in the video as he battles ocean swells in a kayak to reach the few remaining members of a critically endangered species on a rugged, isolated stretch of Hawaiian coastline. “The ocean could suddenly rise up and dash me against the rocks like a piece of driftwood.”

When he arrives at his destination, Perlman starts hauling himself up an impossibly steep, razor-sharp cliff 3,000 feet above the sea without a rope, his fingers sending chunks of rock tumbling down to the waters below. Finally, he reaches the plants and painstakingly transfers pollen from the flowers of one to those of another to ensure that the species can perpetuate itself. At the end of the season, he will return to collect any seeds they were able to produce.

Among the plants for which Perlman, a rock-star botanist with the University of Hawaii’s Plant Extinction Prevention Program , has repeatedly risked his life is Brighamia insignis , better known as cabbage-on-a-stick. One of the strangest-looking species in the Hawaiian flora, with a thick, swollen stem crowned by a rosette of fleshy leaves resembling a head of cabbage, it typically reaches 3 to 6 feet high but has been known to grow up to 16 feet tall. The plant once dotted seaside precipices on two Hawaiian islands, including the spectacular fluted cliffs of Kauai’s Nā Pali coast. But feral goats, rats, and invasive weeds brought to the islands by Polynesians and, later, Europeans decimated the species. What’s more, by the 1970s scientists had come to suspect that it had lost the large moth that they believe once fertilized its fragrant, creamy yellow, trumpet-shaped flowers. Without its pollinator, the plant was unable to produce seeds and its future in the wild was doomed. Had Perlman not come to the rescue, the plant would have faced almost certain extinction.

“When only a few members of a plant species remain, you need to make sure that every little bit of genetic diversity is preserved.”

The fate of cabbage-on-a-stick is now in the hands of another group of emergency botanists. Jeremie Fant, the head of Chicago Botanic Garden’s conservation genetics lab, and his colleagues are experimenting with procedures first developed at zoos to perform high-tech genetic rescue, including the development of a “studbook” that documents the pedigree of surviving individuals of the imperiled species in order to make last-ditch cross-breeding programs possible.

“When only a few members of a plant species remain,” says Fant, “you need to make sure that every little bit of genetic diversity is preserved.”

Scientists like Perlman and Fant work on the knife edge of last-ditch botany to save critically endangered plants like cabbage-on-a-stick because these species can’t produce enough seeds on their own. Plant conservation relies heavily on seed banking. Ideally, seeds are strategically collected from wild populations to ensure that as much of a species’ genetic diversity as possible has been captured. However, a considerable number of plants are so-called exceptional species that cannot be preserved in conventional seed banks. Some are so rare that they suffer from inbreeding and other genetic ailments that impede reproduction, and they don’t produce enough seeds to be banked. Some produce “recalcitrant” seeds that cannot be stored in seed banks because they can’t survive drying and freezing.

The plant known as cabbage-on-a-stick ( Brighamia insignis) has been grown at Limahuli Garden & Preserve on Kauai, which is within the historic range of the species. Seana Walsh

According to Valerie Pence, director of plant research at the Cincinnati Zoo & Botanical Garden’s Center for Conservation & Research of Endangered Wildlife , a conservative estimate is that about 9 percent of threatened species fall into this category. If, as some scientists suspect , as many as one-third of the 500,000 plants believed to exist on earth are at risk, that means that 15,000 exceptional plants could require the kind of botanical intensive care that Perlman and Fant have provided for cabbage-on-a-stick.

Pence has pioneered still another field of emergency botany, developing protocols for in vitro propagation of many exceptional plants and for preserving them in a deep freeze in what she calls “frozen gardens.” But, she says, “the point is that there are a lot of species that will require methods other than traditional seed banking, and some of those methods require additional labor, facilities, and expertise, and are thus more expensive. The question is how are we going to meet this challenge?”

Among the planet’s exceptional plants are not just rare island endemics like cabbage-on-a-stick, but evolutionary relicts such as cycads, palm-like plants with stout trunks, arching crowns of stiff, evergreen leaves, and a 300-million-year lineage, older than any other surviving complex life form. They also include a variety of ecologically and economically important plants around the globe, from oaks and conifers to pawpaws and palms.

Today, only one lone cabbage-on-a-stick plant survives in the wild. It is on the Hawaiian island Kauai and is unable to reproduce.

To ensure the health of their animal populations, zoos and aquariums have for decades engaged in a kind of collaborative family planning. The first studbook created for conservation purposes was set up in 1932 for the European bison. Today, according to Kristine Schad, director of the Association of Zoos and Aquariums’ Population Management Center , studbooks are an integral part of the “Species Survival Plans” for more than 500 animals in the care of members of the organization, which represents over 230 institutions in the United States and abroad. The studbook for each species includes information on the individual animals at zoos and aquariums around the world, such as where they live, who their parents were, where their ancestors came from in the wild, whether they have been bred before, and if so, with whom.

Genetic and population analyses assist with the matchmaking, helping the institutions determine which animals should be bred with each other to ensure that populations are stable, inbreeding is avoided, and all the lineages present in the collective gene pool are preserved in living animals. The goal is to secure stable and genetically diverse populations for the future, and in many cases, to increase the number of animals to replenish depleted populations in their natural habitats.

Some 40 years ago, when Perlman set out to save cabbage-on-a-stick, a couple of hundred plants still grew on the Hawaiian island of Kauai. But two hurricanes destroyed most of them, and today, one lone individual is believed to survive in the wild, unable to reproduce.

A botanist collects pollen from the flower of Brighamia insignis . National Tropical Botanical Garden

Yet the species is more fortunate than many plants on the brink of extinction because, thanks to Perlman’s efforts, it has already been brought into cultivation. Perlman was able to reach and collect seeds from 15 different plants. These were propagated, and hundreds of specimens now grow at various locations operated by Hawaii’s National Tropical Botanical Garden, including Limahuli Garden, close by the species’ natural habitat along the Nā Pali coast. The progeny of these plants are also found in at least 57 botanic gardens around the globe. In addition, hundreds of thousands of specimens have been propagated and sold in recent years by commercial nurseries in the Netherlands. With so many plants safely in cultivation, cabbage-on-a-stick “will not go extinct in my lifetime,” Perlman says.

Recently, however, it became apparent that the National Tropical Botanical Garden’s cabbage-on-a-stick plants were not producing seeds as readily as they once did. Fant and his colleagues decided to help figure out why. Using a database managed by Botanic Gardens Conservation International (BGCI) that includes plant records from about 1,500 of the more than 3,000 botanic gardens worldwide, they tracked where else cabbage-on-a-stick is growing in cultivation. They obtained plants from a number of botanic gardens in North America and Europe, did genetic testing, and discovered that some of the lineages once present in the Hawaiian garden’s plants had been lost. Apparently, the plants were beginning to suffer the effects of inbreeding.

The good news, according to Fant, is that the genetic sampling also found that much of the missing genetic diversity was present in plants at botanic gardens in Berkeley, Chicago, San Diego, and Switzerland, all of which trace their origins to the seeds Perlman collected. “There were six or seven individuals that could be bred back into the National Tropical Botanical Garden plants” to restore genetic diversity, increase seed production, and improve the species’ prospect for long-term survival, he says.

A scientist with the Plant Extinction Prevention Program climbs through remote Hawaiian ecosystems to study endangered plant species. PEPP

Over the past few decades, botanic gardens have taken the lead in efforts to save imperiled plants by creating a backup system in cultivation as a hedge against extinction in the wild. They not only have collected seeds and pollen for safeguarding in seed banks, but also have spearheaded efforts to propagate the species and reintroduce them to their natural habitats. Specialized botanic gardens such as Pence’s in Cincinnati are developing species-specific protocols for preserving a growing number of exceptional plants, including cryopreservation of embryos and other vegetative tissues in a state of suspended animation in liquid nitrogen at -321 degrees Fahrenheit.

One thing botanic gardens haven’t done, says Fant, is see plants as distinct individuals. “Zoos manage their animals as individuals,” he says, “but plants are usually maintained as a collection and rarely is any one individual perceived as a unique member of that species.” This has hindered efforts to save them. Without a studbook tracking the complete pedigree of each genetically unique cabbage-on-a-stick plant in cultivation, for example, it was impossible to ensure that no lineages were being lost. This, Fant and his colleagues wrote in a 2016 paper in the American Journal of Botany , “is clearly not a sustainable solution to managing the thousands of threatened exceptional plant species” held at botanic gardens around the globe.

“We need an eharmony for plants,” says Abby Meyer, executive director of BGCI in the U.S. , referring to the popular online dating site. Meyer has proposed such a botanical matchmaking system, which she calls “integrated collections management.” Like the collaborative system employed at zoos, it would enable gardens to take into account the plants they grow as well as those at other institutions when making decisions about new plants to acquire, crossbreeding, and other measures to preserve the health and diversity of the plants in their care.

Given the grim state of plants around the globe, there’s no time to lose. Currently, says Craig Hilton-Taylor, head of the International Union for Conservation of Nature’s Red List of imperiled species program, 2,787 plants are considered “critically endangered,” defined as suffering “an extremely high risk of extinction.” In many cases, fewer than 50 individuals remain in the wild, putting these plants in a category known in bureaucratic parlance as “CR-D” species. Meyer points out that among these rarest-of-the-rare plants are 43 U.S. native trees, giving the country the dubious distinction of being tied for second place with Madagascar, behind China, as the country with the most CR-D trees.

Plant conservation has not generated nearly the same sense of urgency, nor the funding, that animal conservation has.

According to Hilton-Taylor, in addition to the critically endangered species, 4,269 plants on the Red List are deemed endangered, with “a very high risk of extinction,” and another 5,725 are considered vulnerable, facing “a high risk of extinction” in the wild. Because to date only 8 percent of known plant species have been assessed for inclusion on the Red List, these numbers are certain to rise.

To make matters still more precarious, only 41 percent of the known globally threatened species are protected in cultivation at botanic gardens, and according to Meyer, many are held at just a single institution. She notes that one-third of North American native threatened species are found at only one garden, leaving them at risk from pests, diseases, storms, and other disasters.

Yet plant conservation has not generated nearly the same sense of urgency — nor the funding — that animal conservation has. In the U.S., for example, plants receive just 5 percent of federal dollars spent on species conservation.

A male Wood’s cycad, Encephalartos woodii, of South Africa. The species survives today only in cultivation. Kew Royal Botanic Gardens

In 1999, American biologists James Wandersee and Elisabeth Schussler coined the term “ plant blindness ” to describe humanity’s inability to appreciate the ecological and economic importance of plants, or even to notice the plants all around them. Botanists also blame our lack of empathy for plants for our failure to grapple with the growing threats they face. Consider that cycads, which are coveted by plant collectors because of their beauty and ancient pedigree, have suffered a worldwide poaching crisis worse than that of rhinos, elephants, and other so-called charismatic megafauna. As a result, 75 percent of cycad species are at risk of extinction, yet their plight is not even a blip on the public’s radar screen.

That is certainly not true for beloved animals. For example, when the mate of Tashi, a female rhino at the Buffalo Zoo, passed away, the zoo teamed up with Cincinnati’s Center for Conservation & Research of Endangered Wildlife, which for 10 years had been storing the sperm of Jimmy, a male Indian rhinoceros who had never sired a calf during his lifetime. Jimmy’s sperm was rushed to Buffalo to inseminate Tashi. Sixteen months later, in 2014, the birth of the baby rhino named Monica, conceived through artificial insemination to perpetuate the DNA of a bull that had been dead for a decade, was big news.

While beleaguered rhinos like Jimmy regularly make headlines, there are few heart-wrenching stories about plants like the male Wood’s cycad, Encephalartos woodii, of South Africa, the only member of his species, male or female, ever to be found alive. Today, he survives only in cultivation. Unlike Jimmy the rhino, the handsome cycad, with orange cones and a crown of bright green, 6- to 10-foot-long leaves, has no pet name. And unlike Jimmy, his species will never again reproduce and evolve freely in the wild.

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A solitary herder cares for his goats and the bay area hills, e360 film contest, for 60,000 years, australia’s first nations have put fire to good use, more from e360, slowly but surely, u.s. school buses are starting to electrify, food & agriculture, how agroforestry could help revitalize america’s corn belt, biodiversity, as ‘doomsday’ glacier melts, can an artificial barrier save it, faced with heavier rains, cities scramble to control polluted runoff, in montana’s northern plains, swift foxes are back from the brink, as canadian river shrivels, northern communities call for a highway, in warming world, global heat deaths are grossly undercounted, the ‘internet of animals’ could transform what we know about wildlife, grim dilemma: should we kill one owl species to save another.

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Endangered Species Research (ESR) was founded in 2004 by leading ecologist Professor Otto Kinne as a major stage for publications on the ecology of endangered life, its requirements for survival, and its protection.

ESR has grown dynamically and is recognised as a central journal in this vital field. With its Editorial Board of acknowledged experts from around the world, it attracts papers on a wide range of subjects and species. It publishes Research Articles, Reviews, and Notes, as well as Comments/Reply Comments, Theme Sections and Opinion Pieces. (For more details see the Guidelines for Authors .)

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ESR aims at providing knowledge needed for practising human stewardship of the vast array of the earth’s species, many of which have become threatened, not least by human activities. Such stewardship has become vital for the future of the planet and is of primary importance for the long-term survival of Homo sapiens . While acknowledging that conservation has to occur at a landscape and ecosystem scale, there will always be a need to focus on certain species whose existence is in particular danger. ESR seeks to publish the best of such research that informs conservation or management.

ESR is international and interdisciplinary. It covers all endangered forms of life on Earth, the threats faced by species and their habitats and the necessary steps that must be undertaken to ensure their conservation. ESR publishes high quality contributions reporting research on all species (and habitats) of conservation concern, whether they be classified as Near Threatened or Threatened (Endangered or Vulnerable) by the International Union for the Conservation of Nature and Natural Resources (IUCN) or highlighted as part of national or regional conservation strategies. Submissions on all aspects of conservation science are welcome.

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Systematics and the Conservation of Plant Diversity

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A special issue of Plants (ISSN 2223-7747). This special issue belongs to the section " Plant Systematics, Taxonomy, Nomenclature and Classification ".

Deadline for manuscript submissions: closed (31 October 2021) | Viewed by 28660

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Dear Colleagues,

Systematics and conservation are closely linked areas of knowledge. Supported by the study of morphology, evolution, and classification, Plant Systematics is crucial for the comprehensive knowledge of plant diversity. Besides key objectives – description of species, their relationships, and evolutionary patterns – Plant Systematics is of most relevance for a diverse array of issues and, particularly, for species conservation. Methods in Plant Systematics are changing, as new technological advances offer more effective and powerful tools to deepen our knowledge about plants and to better support conservation planning and management. Without a profound understanding of Earth’s diversity, conservation policies remain incomplete and fragmented.

The continuously declining plant diversity is the main concern of researchers, conservation managers and policy makers. Initiatives to conserve the world's most endangered plant species have taken place in recent decades, and comprehensive assessments of the global conservation status of species have been developed to categorize them according to estimated risks of extinction. These efforts are also crucial to ensure the sustainable use of plant species, irreplaceable resources for food security, nutrition, and human well-being. Relying on a clear recognition of the distinct species, including the cryptic ones, and of their limits, species conservation nowadays goes far beyond ensuring the genetic diversity of populations and ecosystems. These are key components to establish successful conservation strategies.

This Special Issue on “Systematics and the Conservation of Plant Diversity” brings together several research papers that aim to improve the understanding of plant diversity and to ensure their in situ and ex situ conservation .

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Endangered Species

Great Nicobar Island Is a Paradise in Danger

A container port the Indian government plans for this remote island threatens unique Indigenous cultures and biodiversity

Madhusree Mukerjee

How a Cloned Ferret Inspired a DNA Bank for Endangered Species

The birth of a cloned black-footed ferret named Elizabeth Ann, and her two new sisters, has sparked a new pilot program to preserve the tissues of hundreds of endangered species “just in case”

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Deepwater Sharks Are Threatened by Demand for Liver Oil

One in seven species of deepwater sharks and rays is threatened with extinction because of the liver oil and meat trade and emerging fishing technologies that make it possible to catch deep-sea fishes

David Shiffman

Antarctica’s Penguins Could Be Devastated by Avian Influenza

Scientists are watching closely to see whether avian influenza will reach Antarctica before this year’s penguin chicks disperse for the season

Meghan Bartels

Which Lost Species May be Found Again? Huge Study Reveals Clues

There are 856 mammal, bird, amphibian and reptile species currently missing—but researchers continue to search

Daniel Shailer

Cats Kill a Staggering Number of Species across the World

Domestic cats are cherished human companions, but a new study shows the enormous breadth of species the felines prey on when they are left to roam freely

Jack Tamisiea

Golden Mole That Swims through Sand Rediscovered after 86 Years

The iridescent, blind De Winton’s golden mole was last seen in 1937 and later declared officially lost. But scientists have since rediscovered it by tracking its environmental DNA

Samantha Mynhardt, The Conversation US

Restoring the Planet Will Need More than a Climate Price Tag

We can’t put a price on a healthy biosphere. We must instead reorient our economy into one that values the living world

Chirag Dhara, Vandana Singh

Protecting Plants and Animals at Risk Must Start before They Need the Endangered Species Act

The Endangered Species Act is an emergency measure turning 50 this year. Focusing on ecosystem preservation can keep us from ever needing it

The Editors

How AI Can Help Save Endangered Species

Scientists are using artificial intelligence to fight biodiversity loss by analysing vast amounts of data, monitoring ecosystems and spotting trends over time

Tosin Thompson, Nature magazine

Millions of Mosquitoes Will Rain Down on Hawaii to Save an Iconic Bird

Hawaii’s brightly colored honeycreepers are at imminent risk of extinction, and bacteria could be the key to saving them

Wind Energy Could Get Safer for Bats with New Research

Wind turbines threaten several bat species, but the Biden administration is funding research to reduce casualties

Minho Kim, E&E News

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All You Need To Know About Endangered Plants Species

The extinction rate of plants is accelerating at an unprecedented speed: the 2020 State of the World’s Plants and Fungi Report found that 39.4% of the world’s plants are now threatened with extinction, a huge jump from the estimated one in five plants predicted in the 2016 report. There are many endangered plant species that are found all across the world but particularly in biodiversity ‘hotspots’ in the tropics and the Mediterranean. Countries such as Australia, India, and Hawaii have some of the highest amounts of endangered plants. The worrisome trend, experts argue, is desti ned to continue in the upcoming years. Indeed, as a 2018 study by botanist Alan Gray found: “ drivers of plant extinction may have an inertia that could last well into the future”. But what are these drivers, what are the main endangered species of plants, and what are the potential effects of plant loss?

Why Are Plants So Important?

Plants and fungi are the building blocks of life on planet Earth. They are used as medicines and treatments that save the lives of millions of people every year, they represent a source of food and energy, provide humanity with building materials and clean air, and they have the potential to solve urgent problems that threaten human life.

New data that emerged from the 2020 State of the World’s Plants and Fungi Report show that despite the existence of more than 7,000 edible and nutritious plants, 90% of humanity’s food energy intake derives from just 15 plants. Simultaneously, almost half of the world’s population relies on just three crops: rice, maize and wheat. As for their use in medicine, plants make up a huge portion of treatments, used to treat deadly illnesses such as cancer and heart diseases as well as several skin conditions. Approximately 4 billion people rely on herbal medicines as their primary source of healthcare. Out of the top 150 drugs prescribed in the United States, at least 118 are based on natural sources.

But plants are not only crucial for humans. Plant species such as seaweed, for example, are also vital for the conservation of shallow marine ecosystems . These algae break the flow of water and thus help to prevent coastal erosion. They also promote species diversity by providing habitat, nutrients, and energy for millions of animals. 

Another example of vital plants is trees: they represent a precious resource that can help tackle pollution, a threat to human health, climate and ecosystems around the world. According to the 2021 State of the World’s Trees Report , a third of the world’s trees are currently at risk of extinction. 

You might also like: 8 Stunning Endangered Species Facts to Know About

What Are the Drivers of Plant Extinction?

Deforestation, mass-agriculture, logging, and livestock farming are among the top threats to plant diversity. But climate change and extreme weather conditions are considered to be emerging dangers. 

Overharvesting of some plant species to satisfy human needs has placed many medical and food species at risk of extinction. The main drive of overexploitation stems from the unprecedented global demand for naturally-driven medicines and edible plants. Some examples of endangered species of plants that are highly valued for the medicines they provide are Black Cohosh – a root used to support women’s health ailments and to ease arthritis and inflammatory conditions, American and Asian Ginseng – famous for its healing properties, and Wild Yam, used to reduce inflammation and support metabolism.  

As mentioned before, around a dozen plants and just three crops are used to satisfy the food energy intake needs of more than 4 billion people. As experts argue, relying on a handful of crops to feed the global population accounts for the loss of 75% of global farmed plant diversity compared to pre-1900 . Endangered edible plant species include coffee plants -– two-thirds of which are at risk of extinction – cocoa plants, and staple crops such as maize and potatoes. While excessive demand and overexploitation of these plants put them at risk, climate change also plays a large role in their disappearance. As temperatures rise and rainfall drops, pests and diseases are more likely to spread, while insects or mould destroy outdoor crops. The loss of crops further leaves us vulnerable to climate change , contributing to malnutrition by reducing nutrient availability and affecting global food security.

The same discourse goes for the aforementioned seaweed, an overexploited plant used for direct human consumption as well as implemented for the preparation of feeds, fertilisers, biofuels, cosmetics, and medicines. As Juliet Brodie , Professor at the London Natural History Museum, said: “As we continue to exploit our coastal ecosystems, seaweeds face a race against time for us to understand and protect them before it’s too late.”

What Risks Do Endangered Plant Species Pose?

Losing plant species creates a dangerous domino effect as it drives a loss of animal diversity, makes ecosystems even more vulnerable to climate change, extreme weather, and puts human health and the entire food chain at risk. Indeed, ecosystems are a complex network made up of animals, plants, and other organisms coexisting and working together. Losing part of these species can have monumental effects across the entire ecosystem . As experts put it: ‘extinction breeds extinction’. Thus, protecting plant species is thus crucial not only to protect the environment but also to ensure food security and human health. 

What Can We Do to Protect Endangered Plants?

One of the most effective policies to date to protect plants and animal species threatened with extinction is the Endangered Species Act (ESA). The law, passed in the US in 1973, allows individuals and organisations to petition to have a species listed as endangered or threatened. After undergoing scientific review, classified endangered species are to be protected and to do so, long-term recovery plans for critical habitat areas are set up to prevent extinction. These plans cover a range of factors such as habitat, food availability, reproduction rate, and climate. 

The law is still the country’s best – and only – option to protect endangered species. And while it has proven to be more than 99% successful at preventing extinction, given that at least 227 endangered species have been saved since the law was passed five decades ago, there are other ways to help conserve plants and protect those at risk of extinction that everyone can do. First and foremost, we can educate ourselves and the people around us about threatened species, researching what plants are at risk in the areas we live in and the potential consequences we would face if they were to disappear. Another important way is to preserve the environment around us, leaving it untouched and undisturbed. Avoiding toxic pesticides and herbicides in our yard is also crucial, as the chemicals contained in these products are extremely detrimental. As for edible plants such as coffee and cocoa, opting for Fair Trade brands, whose production is ethical and involves the least amount of environmental destruction, is always a good choice. Finally, people must commit to reducing their environmental footprint as much as possible, avoiding activities that can pollute the habitat around us, and being conscious that our actions can have detrimental effects.

You might also like: 10 of the World’s Most Endangered Animals in 2022

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To save endangered trees, researchers in South America recruit an army of fungi

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• Mycorrhizal fungi live in symbiosis with plants, providing them with nutrients necessary to thrive and potentially playing a key part in preserving threatened species.
• Although research into mycorrhizae has so far been sparse in Latin America, efforts are gaining momentum, with experts studying how the fungi could help save the Colombian black oak, an endangered, endemic species.
• In Huila, Colombia, local communities are successfully working with researchers on a black oak restoration project using seeds “inoculated” with fungi.

It’s a sunny July day during an otherwise exceptionally rainy season in the lush green mountains of Huila, in Colombia’s eastern Andes. Adriana Corrales, her assistant and a local guide climb through the dense cloud forest. Above them, birds sing and monkeys howl through the canopy of ancient Colombian black oaks ( Trigonobalanus excelsa ), an endangered tree species. But the researchers keep their eyes on the ground.

“All this forest above us, and we are here looking down,” says Corrales, a fungi ecologist and expedition leader at the Society for the Protection of Underground Networks (SPUN), a nonprofit research organization mapping fungi worldwide. For the last two years, the group has been searching in Colombia’s black oak forests for mycorrhizae, a type of fungi that establishes a unique symbiosis with plants that’s fundamental to keeping forests alive.

Most plants worldwide are associated with these fungi. Mycorrhizae grow around roots, forming vast networks of thin, cotton-like filaments that extend into the lower soil levels and reach the litter fall. Through this system, the fungi can break down organic matter, such as dry leaves, and even mine minerals in rocks and deliver water and essential nutrients directly to plants’ roots. In return, the roots provide the fungi with sugars, essential for their survival.

“The fungi form a microbiome on the plant’s roots in the same way that microbes in our gut help us digest food,” Corrales says. “We have these bacteria in our gut that break down the food we eat so we can absorb it. In this case, the fungi digest the food in the soil and bring the nutrients to the plant in exchange for sugar.”

Although researchers have been looking into this symbiosis since the late 19th century, no single genome of tropical mycorrhizal fungi from South America has ever been sequenced, compared to hundreds elsewhere. Among the reasons are lack of funding and difficulty accessing areas with fungi. But Corrales and other experts plan to change that.

Studying and understanding the local mycorrhizal fungi, they say, is fundamental to preserving local endangered plant species, like the endemic Colombian black oak. Its genus is thought to represent the oldest type of oak in the world. Scientists think the species is a remnant of an old oak lineage established up to 100 million years ago in what is today North America.

It’s believed that this oak once covered most of Colombia’s high-altitude regions. After centuries of deforestation for timber and agriculture, the black oak has become endangered and can be found only in five areas of Colombia in fragmented patches, covering a combined area smaller than 50,000 hectares (124,000 acres), according to a conservation assessment .

A fungi hotspot

Every now and then, the buzz of a chainsaw echoes through the patch of forest where Corrales and her colleagues, armed with liquid nitrogen, a hammer and some plastic bags, sample fungi to understand their role in protecting the black oak. The area is flanked by Huila’s encroaching coffee farms.

“Oh, this one is so beautiful! Spectacular!” Corrales yells as she cuts a purple-capped mushroom, the size of her pinky finger, from the ground. Finding a mushroom indicates that there’s a whole unseen organism underground. “It looks like they are made of sugar candy,” she says.

This particular species of mycorrhizal fungus is a new-to-science species in the genus Russula , which Corrales previously discovered in Panama. In the 15 years she spent there studying fungi, she found a total of 20 new-to-science species.

When the experts find mushrooms, they first inspect them with the naked eye. Then they smell them. Some mushrooms of the Russulaceae family smell like fish, while others, like those of the genus Lactarius, have a hint of honey or maple syrup. Sometimes the researchers even bite off a little piece of the mushroom and then spit it out to avoid poisoning. “This one is bitter,” Corrales tells her assistant after brushing her lips with a fat-stemmed yellow mushroom.

At night, back at their hotel bungalows in the jungle, they store their finds in plastic boxes out on the balcony. They then use a surgical knife to cut off a piece of each mushroom for detailed DNA analysis.

These samples are sent to labs in the U.S. to sequence their genomes and run them against international databases of the DNA of all known fungi species. This kind of analysis, called DNA barcoding, helps researchers classify the species — or indicates that they may have encountered a new-to-science species and classify them.

The complete genome can also reveal different characteristics of the species, such as their functions, what kinds of nutrients they obtain more effectively, and how they might interact with the trees around them. Corrales says she hopes to sequence the DNA of up to 200 mycorrhizal fungi species with funding from the Joint Genome Institute (JGI) , a U.S. Department of Energy research center at the Lawrence Berkeley National Laboratory.

To identify potential fungi connections to trees, Corrales’s team also collects soil samples from around the black oaks.

A single tree can be connected to several fungi species. It’s been estimated that a spoonful of soil can contain up to 100 meters (330 feet) of mycorrhizal threads. Corrales has found about 250 different kinds of mycorrhizae in soil samples taken near Colombian black oaks, many of which she says might be unique to the region and new to science.

Corrales’s analysis has found the soil samples here to be very acidic and high in phosphorus, generally uncommon in nutrient-poor tropical soils. She says the fungi might be helping the oaks absorb the phosphorus and thrive in the adverse acidic soils. “The fungi change the biochemical composition of the soil to benefit the oak,” she tells Mongabay.

Using fungi for conservation

Research into mycorrhizal fungi’s links with endangered tree species could help conservation efforts. A 2019 review of 26 studies found that adding mycorrhizae to plants can enhance ecological restoration outcomes, increasing the number of species in plant communities by 30%.

Two years ago, in partnership with Colombia’s University of the Rosary and the Swiss nonprofit Franklinia Foundation, Corrales and local community members started a black oak restoration project . They collected tree seeds and “inoculated” them with mycorrhizae. They then planted about 3,000 of these seeds in greenhouse pots filled with fungi-rich soil from the forest. Although previous attempts to grow black oak from seeds had been unsuccessful, Corrales says the fungi present in the soil made the seedlings grow strong.

“The black oak is an umbrella species for fungi: one single plant can be related to hundreds of fungi,” she says. “The plant cannot survive without the fungi, and the fungi cannot survive without the plant.”

To date, community members have replanted 424 black oaks in forest fringes, deforested lands and near water bodies. Nelly Salazar Asturillo, who owns a small organic coffee farm outside the town of Pitalito, in southern Huila, helped grow 90 saplings in her backyard, which were distributed to other locals. Asturillo’s family keeps an intact 19-hectare (47-acre) black oak forest on her land. “By preserving the oak, more and more birds are around, and it doesn’t get as hot as before,” she says. “For many years, we haven’t seen beehives around, and now the bees are also coming back.”

Lucia Urbano, another local coffee farmer, used to cut and burn black oaks to make charcoal for sale. A few years ago, as she tells it, she went up the mountain and asked nature for forgiveness, before establishing a 25-hectare (62-acre) reserve on her property and planting 40 black oak saplings. “Looking back at the deforestation, lack of water and climate change, I became more aware of the need to preserve the trees,” she says. “I have children and grandchildren and worry about their future here.”

Latin America boosts fungi research

In Argentina, Valeria Faggioli, a biologist at the National Agricultural Technology Institute, has been studying mycorrhizal fungi associated with the endangered monkey puzzle tree ( Araucaria araucana ) in remnants of the Atlantic Forest close to the famed Iguazú Falls. The monkey puzzle tree almost went extinct due to logging, and the commercial trade in wild-sourced specimens has been prohibited since 1990.

Faggioli says she hopes to isolate the spores of the fungi present in monkey puzzle forests to multiply them in the lab and inoculate seeds for reforestation projects. “Whatever we have lost due to land use and deforestation during the last centuries remains in the preserved forest soil,” Faggioli says. “Any attempt to restore degraded lands will demand going to the origins of the native habitat.”

In Chile, César Marín, a fungi ecologist at Santo Tomas University, is studying how fungi partner with the alerce tree ( Fitzroya cupressoides ), an iconic local endangered species. Alerce is the largest tree species in South America, growing up to 50 m (164 ft) tall. Marín has been collecting fungi at Alerce Costero National Park around the longest-living specimen of this tree, believed to be the oldest tree alive worldwide, at 5,400 years old. Chile aims to reforest 100 hectares (250 acres) of alerce in its national parks over the next three years; Marín says the fungi he’s collecting can help achieve this goal.

“More and more studies have shown it is a triple alliance between plants, fungi and the bacteria that absorb nutrients and pass them on to the fungi,” Marín tells Mongabay.

He adds more reforestation projects need to be based on fungi. Some research has shown that in certain conditions, such as in soils with high levels of phosphorus, the same mycorrhizal fungi that are helpful to trees can turn parasitic, damaging the plants. “It all depends on each place and context; that is why we need serious studies.”

David Janos, a retired mycorrhizae expert at the University of Miami, agrees. Janos says moving soils around can be dangerous and potentially spread diseases and parasites. He also notes that the community of fungi that trees need to grow might change over time. “There will always be the question of whether the right kind of mycorrhiza is present in a reforestation effort,” Janos says, highlighting the importance of using native fungi whenever possible.

Most researchers agree that for a balanced and healthy ecosystem, we need to preserve both the trees and the fungi they partner with. “It is a mutualistic relationship that has to be taken into account in any restoration project. But often, projects ignore what is underground,” Corrales says. “We need to develop a more ecosystemic vision of forests. If the black oak disappears, the fungi also do, and if the fungi disappear, so will the oaks.”

Neuenkamp, L., Prober, S. M., Price, J. N., Zobel, M., & Standish, R. J. (2019). Benefits of mycorrhizal inoculation to ecological restoration depend on plant functional type, restoration context and time.  Fungal Ecology ,  40 , 140-149. doi: 10.1016/j.funeco.2018.05.004

Banner image : According to researchers in Colombia, studying and understanding local mycorrhizal fungi fundamental to preserving local endangered plant species. Image courtesy of Sofia Moutinho.

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Saving Endangered Species: A Case Study Using Global Amphibian Declines

How are Endangered Species Identified?

The International Union for Conservation of Nature and Natural Resources (IUCN) Red List uses a hierarchical structure of nine categories for assigning threat levels for each species or subspecies. These categories range from 'Extinct' to 'Least Concern' (Figure 1). At the highest levels of threat, taxa are listed as 'Critically Endangered,' 'Endangered,' or 'Vulnerable,' all of which are given 'Threatened' status. A series of quantitative criteria is measured for inclusion in these categories, including: reduction in population size, geographic range size and occupancy of area, total population size, and probability of extinction. The evaluation of these criteria includes analyses regarding the number of mature individuals, generation time, and population fragmentation. Each taxon is appraised using all criteria. However, since not all criteria are appropriate for assessing all taxa, satisfying any one criterion qualifies listing at that designated threat level.

There are a variety of human activities that contribute to species becoming threatened, including habitat destruction, fragmentation, and degradation, pollution, introduction of non-native species, disease, climate change, and over-exploitation. In many cases, multiple causes act in concert to threaten populations. Though the causes underlying population declines are numerous, some traits serve as predictors of whether species are likely to be more vulnerable to the causes listed. For example, many species that have become endangered exhibit large body size, specialized diet and/or habitat requirements, small population size, low reproductive output, limited geographic distribution, and great economic value (McKinney 1997).

How to Save Endangered Species

There are a variety of methods currently being implemented to save endangered species. The most common are creation of protected areas, captive breeding and reintroduction, conservation legislation, and increased public awareness.

Protected areas

An effective and internationally recognized strategy for conserving species and ecosystems is to designate protected areas. The United Nations Environment Programme World Conservation Monitoring Center (UNEP-WCMC) defines a protected area as "an area of land and/or sea especially dedicated to the protection of biological diversity and of natural and associated cultural resources, managed through legal or other effective means." Worldwide, extensive systems of protected areas have been developed and include national parks, state/provincial parks, wildlife refuges, and nature reserves, all of which differ in their management objectives and degree of protection. The IUCN has defined six protected area management categories, based on primary management objective (Table 1). These categories are defined in detail in the Guidelines for Protected Areas Management Categories published by IUCN in 1994.

protected area managed mainly for science
Area of land and/or sea possessing some outstanding or representative ecosystems, geological or physiological features and/or species, available primarily for scientific research and/or environmental monitoring.
protected area managed mainly for wilderness protection
Large area of unmodified or slightly modified land, and/or sea, retaining its natural character and influence, without permanent or significant habitation, which is protected and managed so as to preserve its natural condition.
protected area managed mainly for ecosystem protection and recreation
Natural area of land and/or sea, designated to (a) protect the ecological integrity of one or more ecosystems for present and future generations, (b) exclude exploitation or occupation inimical to the purposes of designation of the area and (c) provide a foundation for spiritual, scientific, educational, recreational and visitor opportunities, all of which must be environmentally and culturally compatible.
protected area managed mainly for conservation of specific natural features
Area containing one or more specific natural or natural/cultural feature which is of outstanding or unique value because of its inherent rarity, representative or aesthetic qualities or cultural significance.
protected area managed mainly for conservation through management intervention
Area of land and/or sea subject to active intervention for management purposes so as to ensure the maintenance of habitats and/or to meet the requirements of specific species.
protected area managed mainly for landscape/seascape conservation and recreation
Area of land, with coast and sea as appropriate, where the interaction of people and nature over time has produced an area of distinct character with significant aesthetic, ecological and/or cultural value, and often with high biological diversity. Safeguarding the integrity of this traditional interaction is vital to the protection, maintenance and evolution of such an area.
protected area managed mainly for the sustainable use of natural ecosystems
Area containing predominantly unmodified natural systems, managed to ensure long term protection and maintenance of biological diversity, while providing at the same time a sustainable flow of natural products and services to meet community needs.

The World Database on Protected Areas (WDPA) records all nationally designated terrestrial and marine protected areas whose extent is known. These data are collected from national and regional governing bodies and non-governmental organizations. Currently, there are over 120,000 protected areas (2008 estimate, UNEP-WCMC), covering about 21 million square kilometers of land and sea. Since 1872, there has been a dramatic increase in the global number and extent of nationally designated protected areas (Figure 2). Well-planned and -managed protected areas not only benefit species at risk, but other species associated with them, thereby increasing the overall amount of biodiversity conserved. Despite increases in the size and number of protected areas, however, the overall area constitutes a small percentage of the earth's surface. Because these areas are critical to the conservation of biodiversity, the designation of more areas for protection and increases in the sizes of those areas already in existence are necessary.

Another opportunity for creating protected areas is the Alliance for Zero Extinction (AZE), an international consortium of conservation organizations that specifically targets protection of key sites that represent sanctuaries of one or more Endangered or Critically Endangered species. The AZE focuses on species whose habitats have been degraded or whose ranges are exceptionally small, making them susceptible to outside threats. Three criteria must be met in order to prioritize a site for protection (Table 2). To date, 588 sites encompassing 920 threatened species of mammals, birds, reptiles, amphibians, conifers and corals have been identified. The goal of such efforts is to prevent the most imminent species extinctions by increasing global awareness of these key areas.

Endangerment An AZE site must contain at least one Endangered or Critically Endangered species, as listed on the IUCN Red List. Irreplaceability An AZE site should only be designated if it is the sole area where and Endangered or Critically Endangered species occurs, contains the overwhelmingly significant known resident population (>95%) of the Endangered or Critically Endangered species, or contains the overwhelmingly significant known population (>95%) for one life history segment (e.g. breeding or wintering) of the Endangered or Critically Endangered species. Discreteness The area must have a definable boundary within the character of habitats, biological communities, and/or management issues have more in common with each other than they do with those in adjacent areas.

Captive breeding and reintroduction

Some species in danger of extinction in the wild are brought into captivity to either safeguard against imminent extinction or to increase population numbers. The primary goals of captive breeding programs are to establish populations via controlled breeding that are: a) large enough to be demographically stable; and b) genetically healthy (Ebenhard 1995). These objectives ensure that populations will exhibit a healthy age structure, resistance to disease, consistent reproduction, and preservation of the gene pool to minimize and/or avoid problems associated with inbreeding. Successful captive breeding programs include those for the Guam rail, scimitar-horned oryx, and Przewalski's horse. (See iucnredlist.org for details.)

Establishing captive populations is an important contribution of zoos and aquariums to the conservation of endangered species. Zoos and aquariums have limited space, however, so to maintain healthy populations, they cooperate in managing their collections as breeding populations from international to regional levels. The World Association of Zoos and Aquariums (WAZA) is the organization that unites the world's zoos and aquariums in cooperative breeding programs. Perhaps the most important tools in managing these programs are studbooks, which ensure that captive populations maintain a sufficient size, demographic stability, and ample genetic diversity. All information pertinent to management of the species in question is included (e.g., animal registration number, birth date, parentage, behavioral traits that may affect breeding). These studbooks are used to make recommendations regarding which individuals should be bred, how often, and with whom in order to minimize inbreeding and, thus, enhance the demographic and genetic security of the captive population.

Another goal of some captive breeding programs is to reintroduce animals to the wild to reestablish populations. Examples of successful introductions using captive-bred stock include California condors (Ralls & Ballou 2004) and black-footed ferrets (Russell et al. 1994). Reintroductions can also utilize individuals from healthy wild populations, meaning individuals that are thriving in one part of the range are introduced to an area where the species was extirpated. Reintroduction programs involve the release of individuals back into portions of their historic range, where they are monitored and either roam freely (e.g., gray wolves released in Yellowstone National Park) or are contained within an enclosed area (e.g., elk in Land Between the Lakes National Recreation Area in western Kentucky; Figure 3). However, reintroduction is only feasible if survival can be assured. Biologists must ascertain whether: a) the original threats persist and/or can be mitigated; and b) sufficient habitat remains, or else survival will be low upon release.

Laws and regulations

Biodiversity is protected by laws at state/provincial, national, and international levels. Arguably the most influential law is the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) which is an agreement between governments (i.e., countries) that controls international trade in wild animals, plants, and their parts to ensure continued survival. International trade in wildlife is a multi-billion dollar industry that affects millions of plants and animals. As a result, CITES lists species in three Appendices according to the level of protection they require to avoid over-exploitation; species listed in Appendix I require the most protection and, thus, trade limitations (Table 3). Currently, approximately 30,000 species are protected under CITES (Table 4).

Appendix Level of Protection Trade Appendix I Species threatened with extinction Permitted only in exceptional circumstances Appendix II Species might be threatened with extinction but not required Trade is controlled to ensure survival Appendix III Species are protected in at least one country Trade is controlled after a member country has indicated that assistance is needed in this capacity   Appendix I Appendix II Appendix III Mammals 297 spp. + 23 sspp. 492 spp. + 5 sspp. 44 spp. + 10 sspp. Birds 156 spp + 11 sspp. 1275 spp. + 2 sspp. 24 spp. Reptiles 76 spp. + 5 sspp. 582 spp. 56 spp. Amphibians 17 spp. 113 spp. 1 sp. Fish 15 spp. 81 spp. - Invertebrates 64 spp. + 5 sspp. 2142 spp. + 1 sspp. 22 spp. + 3 sspp. Plants 301 spp. + 4 sspp. 29105 spp. 119 spp. + 1 sspp.

The trade in wildlife is an international issue and, as such, cooperation between countries is required to regulate trade under CITES. However, member countries adhere to regulations voluntarily and, consequently, they must implement them. Most important, CITES does not take the place of national laws; member countries must also have their own domestic legislation in place to execute the Convention.

Public awareness

In general, the public is unaware about the current extinction crisis. Public awareness can be increased through education and citizen science programs. Conservation education often begins in elementary school and may be enhanced through summer camps or family vacations that are nature oriented (e.g., involve visiting national or state parks). Early positive experiences with nature are essential for children to gain an appreciation for wildlife and the problems species face. In high school, this education is continued through formal science education and extra-curricular activities. Other means of increasing public awareness involve internet websites where subscribers can receive emails from conservation organizations like Defenders of Wildlife, Environmental Defense, and World Wildlife Fund. In many cases, these organizations provide updates on the status of endangered species and promote letter writing to elected officials in requesting protection for endangered species and their habitats.

CASE STUDY IN CONSERVATION: Global declines in amphibian populations

Amphibians are one of the earth's most imperiled vertebrate groups, with approximately one-third of all species facing extinction (Stuart et al . 2004). Causes of amphibian population declines and extinctions echo those listed in the introductory paragraphs but primarily consist of drainage and development of wetland habitats and surrounding uplands, contamination of aquatic habitats, predation by or hybridization with introduced species, climate change, and over-harvesting (Collins & Storfer 2003). In addition, the recent declines observed in relatively pristine areas, such as state, provincial, and national parks worldwide have brought to light the tremendous impact of pathogens on amphibian populations, most notably that of the amphibian-killing fungus Batrachochytrium dendrobatidis (Bd). So what is being done to preserve amphibian diversity?

To address the historic sources of amphibian population declines, such as overexploitation and habitat loss, national and international legislation exists to monitor the trade in amphibians and prevent further reductions in available habitat. Although international trade in amphibians is less common relative to trade in other vertebrate groups, CITES currently lists 131 species in Appendices I-III. Furthermore, IUCN currently lists 509, 767, and 657 amphibian species as Critically Endangered, Endangered, or Vulnerable (Figure 4), respectively. These species' native habitats are afforded protection at various levels of organization. The AZE has identified 588 sites worldwide exhibiting at least one criterion for protection (Table 2), and these sites are home to hundreds of amphibian species listed by IUCN as between Vulnerable and Critically Endangered. In addition, IUCN's Amphibian Specialist Group (ASG) has partnered with governmental and non-governmental organizations and individuals to create new protected areas and minimize further population declines due to habitat fragmentation and loss. In addition to designation of new protected areas, efforts of the ASG include habitat restoration, promotion of ecotourism, and extended amphibian-monitoring programs.

Despite efforts to preserve suitable habitat, biologists became increasingly aware of catastrophic population declines associated with Bd, and more urgent action became necessary when declines were detected in protected areas with minimal risks of habitat loss and overexploitation. Batrachochytrium dendrobatidis is a parasitic fungus that disrupts the bodily processes of its amphibian hosts, resulting in lethargy and ultimately death. Although the exact origins of this pathogen are currently debated, Bd has been detected throughout the world and linked to dramatic amphibian population declines and extinctions (Skerratt et al . 2007).

Due to the rapidity with which Bd invades amphibian communities, swift conservation action was deemed necessary to prevent extinctions; consequently, many institutions realized the necessity of collecting wild individuals prior to the arrival of Bd with the hopes of establishing captive populations. The Amphibian Ark, for example, represents a joint effort between the ASG, the World Association of Zoos and Aquariums, and the IUCN/SSC Conservation Breeding Specialist Group. Members of these organizations worldwide participate in captive amphibian husbandry and breeding programs using wild-caught individuals (Figure 5-6). In concert with such activities, some facilities are also addressing the possibility of 'biobanking' activities, such as cryogenically preserving the sperm and eggs of imperiled species or maintaining living cell lines for future use. While some researchers are dedicated to maintaining captive populations, others are actively investigating potential treatments for Bd or preventative measures. Treatment methods are currently being investigated for amphibians already infected with Bd (Berger et al . 2010), and findings that certain bacteria confer Bd resistance have led some researchers to examine the viability of 'seeding' amphibians with protective bacterial coatings prior to reintroduction efforts (Becker and Harris 2010). Also, biologists are increasingly advocating for more rigorous chytrid monitoring protocols to prevent further spread of this pathogen, such as efforts in the United States to incorporate amphibians into the Lacey Act (1900), a federal mandate that would require them to be certified as disease-free prior to importation.

Throughout the current amphibian extinction crisis, increasing public awareness has been a critical component of conservation efforts. Amphibians typically do not receive the attention bestowed upon more charismatic megafauna, such as pandas and tigers, despite their significant economic, ecological, and aesthetic values. In a worldwide effort to bring amphibian population declines to the forefront, the Amphibian Ark declared 2008 as the "Year of the Frog," a time in which conservationists showcased amphibian diversity in zoos and aquaria while detailing their current plight. In addition, some conservation efforts, such as Project Golden Frog, utilize attractive or otherwise conspicuous amphibians as flagship species with which to garner public interest and local pride in endangered species and promote local activism (Figure 7). The ASG's 'Metamorphosis' initiative utilizes artistry to promote increase public recognition of connections between the plight of amphibians and that of humanity. Biologists have also solicited direct public involvement through citizen science programs wherein non-scientists can participate in crucial amphibian population monitoring efforts; examples of these efforts include ASG's Global Amphibian BioBlitz, Nature Canada, and Environment Canada's FrogWatch, the United States Geological Survey's North American Amphibian Monitoring Program, and the AZA's FrogWatch USA. Finally, continued research highlighting the critical ecological and economic roles amphibians play in ecosystems, such as transferring energy through food webs and reducing insect populations (Davic & Welsh 2004), has been important in cultivating popular interest in the current extinction crisis.

References and Recommended Reading

Berger, L., Speare R. et al . Treatment of chtridiomycosis requires urgent clinical trials. Diseases of Aquatic Organisms 92 , 165-174 (2010).

Collins, J. P. & Storfer, A. Global amphibian declines: sorting the hypotheses. Diversity and Distributions 9 , 89-98 (2003).

Davic, R. D. & Welsh, H. H. On the ecological roles of salamanders. Annual Review of Ecology, Evolution, and Systematics 35 , 404-434 (2004).

Ebenhard, T. Conservation breeding as a tool for saving animal species from extinction. Trends in Ecology and Evolution 10 , 438-443 (1995).

McKinney, M. L. Extinction vulnerability and selectivity: combining ecological and paleontological views. Annual Review of Ecology and Evolution 28 , 495-516 (1997).

Ralls, K. & Ballou, J. D. Genetic status and management of California condors. Condor 106 , 215-228 (2004).

Russell, W. C., Thorne, E. T. et al. The genetic basis of black-footed ferret reintroduction. Conservation Biology 8 , 163-266 (1994).

Skerratt, L. F., Berger, L. et al . Spread of chytridiomycosis has caused the rapid global decline and extinction of frogs. Ecohealth 4 , 125-134 (2007).

Stuart, S. N., Chanson, J. S. et al. Status and trends of amphibian declines and extinctions worldwide. Science 306 , 1783-1786 (2004).

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Endangered Species

An endangered species is a type of organism that is threatened by extinction. Species become endangered for two main reasons: loss of habitat and loss of genetic variation.

Biology, Ecology, Geography, Conservation

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An endangered species is a type of organism that is threatened by extinction . Species become endangered for two main reasons: loss of habitat and loss of genetic variation . Loss of Habitat A loss of habitat can happen naturally. Nonavian dinosaurs , for instance, lost their habitat about 65 million years ago. The hot, dry climate of the Cretaceous period changed very quickly, most likely because of an asteroid striking Earth. The impact of the asteroid forced debris into the atmosphere , reducing the amount of heat and light that reached Earth’s surface. The dinosaurs were unable to adapt to this new, cooler habitat. Nonavian dinosaurs became endangered, then extinct . Human activity can also contribute to a loss of habitat. Development for housing, industry , and agriculture reduces the habitat of native organisms. This can happen in a number of different ways. Development can eliminate habitat and native species directly. In the Amazon rainforest of South America, developers have cleared hundreds of thousands of acres. To “clear” a piece of land is to remove all trees and vegetation from it. The Amazon rainforest is cleared for cattle ranches , logging , and ur ban use. Development can also endanger species indirectly. Some species, such as fig trees of the rainforest, may provide habitat for other species. As trees are destroyed, species that depend on that tree habitat may also become endangered. Tree crowns provide habitat in the canopy , or top layer, of a rainforest . Plants such as vines, fungi such as mushrooms, and insects such as butterflies live in the rainforest canopy. So do hundreds of species of tropical birds and mammals such as monkeys. As trees are cut down, this habitat is lost. Species have less room to live and reproduce . Loss of habitat may happen as development takes place in a species range . Many animals have a range of hundreds of square kilometers. The mountain lion ( Puma concolor ) of North America, for instance, has a range of up to 1,000 square kilometers (386 square miles). To successfully live and reproduce, a single mountain lion patrols this much territory. Urban areas , such as Los Angeles, California, U.S.A., and Vancouver, British Columbia, Canada, grew rapidly during the 20th century. As these areas expanded into the wilderness, the mountain lion’s habitat became smaller. That means the habitat can support fewer mountain lions. Because enormous parts of the Sierra Nevada, Rocky, and Cascade mountain ranges remain undeveloped, however, mountain lions are not endangered. Loss of habitat can also lead to increased encounters between wild species and people. As development brings people deeper into a species range, they may have more exposure to wild species. Poisonous plants and fungi may grow closer to homes and schools. Wild animals are also spotted more frequently . These animals are simply patrolling their range, but interaction with people can be deadly. Polar bears ( Ursus maritimus ), mountain lions, and alligators are all predators brought into close contact with people as they lose their habitat to homes, farms , and businesses. As people kill these wild animals, through pesticides , accidents such as collisions with cars, or hunting, native species may become endangered.

Loss of Genetic Variation Genetic variation is the diversity found within a species. It’s why human beings may have blond, red, brown, or black hair. Genetic variation allows species to adapt to changes in the environment. Usually, the greater the population of a species, the greater its genetic variation. Inbreeding is reproduction with close family members. Groups of species that have a tendency to inbreed usually have little genetic variation, because no new genetic information is introduced to the group. Disease is much more common, and much more deadly, among inbred groups. Inbred species do not have the genetic variation to develop resistance to the disease. For this reason, fewer offspring of inbred groups survive to maturity. Loss of genetic variation can occur naturally. Cheetahs ( Acinonyx jubatus ) are a threatened species native to Africa and Asia. These big cats have very little genetic variation. Biologists say that during the last Ice Age , cheetahs went through a long period of inbreeding. As a result, there are very few genetic differences between cheetahs. They cannot adapt to changes in the environment as quickly as other animals, and fewer cheetahs survive to maturity. Cheetahs are also much more difficult to breed in captivity than other big cats, such as lions ( Panthera leo ). Human activity can also lead to a loss of genetic variation. Overhunting and overfishing have reduced the populations of many animals. Reduced population means there are fewer breeding pairs . A breeding pair is made up of two mature members of the species that are not closely related and can produce healthy offspring. With fewer breeding pairs, genetic variation shrinks. Monoculture , the agricultural method of growing a single crop , can also reduce genetic variation. Modern agribusiness relies on monocultures. Almost all potatoes cultivated , sold, and consumed, for instance, are from a single species, the Russet Burbank ( Solanum tuberosum ). Potatoes, native to the Andes Mountains of South America, have dozens of natural varieties. The genetic variation of wild potatoes allows them to adapt to climate change and disease. For Russet Burbanks, however, farmers must use fertilizers and pesticides to ensure healthy crops because the plant has almost no genetic variation. Plant breeders often go back to wild varieties to collect genes that will help cultivated plants resist pests and drought, and adapt to climate change. However, climate change is also threatening wild varieties. That means domesticated plants may lose an important source of traits that help them overcome new threats. The Red List The International Union for Conservation of Nature (IUCN) keeps a “Red List of Threatened Species.” The Red List de fines the severity and specific causes of a species’ threat of extinction. The Red List has seven levels of conservation: least concern , near threatened , vulnerable, endangered, critically endangered , extinct in the wild , and extinct. Each category represents a different threat level. Species that are not threatened by extinction are placed within the first two categories—least concern and near-threatened. Those that are most threatened are placed within the next three categories, known as the threatened categories —vulnerable, endangered, and critically endangered. Those species that are extinct in some form are placed within the last two categories—extinct in the wild and extinct. Classifying a species as endangered has to do with its range and habitat, as well as its actual population. For this reason, a species can be of least concern in one area and endangered in another. The gray whale ( Eschrichtius robustus ), for instance, has a healthy population in the eastern Pacific Ocean, along the coast of North and South America. The population in the western Pacific, however, is critically endangered.

Least Concern Least concern is the lowest level of conservation . A species of least concern is one that has a widespread and abundant population. Human beings are a species of least concern, along with most domestic animals , such as dogs ( Canis familiaris ) and cats ( Felis catus ). Many wild animals, such as pigeons and houseflies ( Musca domestica ), are also classified as least concern. Near Threatened A near threatened species is one that is likely to qualify for a threatened category in the near future. Many species of violets , native to tropical jungles in South America and Africa, are near threatened, for instance. They have healthy populations, but their rainforest habitat is disappearing at a fast pace. People are cutting down huge areas of rainforest for development and timber . Many violet species are likely to become threatened. Vulnerable Species The definitions of the three threatened categories (vulnerable, endangered, and critically endangered) are based on five criteria: population reduction rate , geographic range, population size, population restrictions , and probability of extinction . Threatened categories have different thresholds for these criteria. As the population and range of the species decreases, the species becomes more threatened. 1) Population reduction rate A species is classified as vulnerable if its population has declined between 30 and 50 percent. This decline is measured over 10 years or three generations of the species, whichever is longer. A generation is the period of time between the birth of an animal and the time it is able to reproduce. Mice are able to reproduce when they are about one month old. Mouse populations are mostly tracked over 10-year periods. An elephant's generation lasts about 15 years. So, elephant populations are measured over 45-year periods. A species is vulnerable if its population has declined at least 50 percent and the cause of the decline is known. Habitat loss is the leading known cause of population decline. A species is also classified as vulnerable if its population has declined at least 30 percent and the cause of the decline is not known. A new, unknown virus , for example, could kill hundreds or even thousands of individuals before being identified. 2) Geographic range A species is vulnerable if its “ extent of occurrence ” is estimated to be less than 20,000 square kilometers (7,722 square miles). An extent of occurrence is the smallest area that could contain all sites of a species’ population. If all members of a species could survive in a single area, the size of that area is the species’ extent of occurrence. A species is also classified as vulnerable if its “ area of occupancy ” is estimated to be less than 2,000 square kilometers (772 square miles). An area of occupancy is where a specific population of that species resides. This area is often a breeding or nesting site in a species range. 3) Population size Species with fewer than 10,000 mature individuals are vulnerable. The species is also vulnerable if that population declines by at least 10 percent within 10 years or three generations, whichever is longer. 4) Population restrictions Population restriction is a combination of population and area of occupancy. A species is vulnerable if it is restricted to less than 1,000 mature individuals or an area of occupancy of less than 20 square kilometers (8 square miles). 5) Probability of extinction in the wild is at least 10 percent within 100 years. Biologists, anthropologists, meteorologists , and other scientists have developed complex ways to determine a species’ probability of extinction. These formulas calculate the chances a species can survive, without human protection, in the wild. Vulnerable Species: Ethiopian Banana Frog The Ethiopian banana frog ( Afrixalus enseticola ) is a small frog native to high- altitude areas of southern Ethiopia. It is a vulnerable species because its area of occupancy is less than 2,000 square kilometers (772 square miles). The extent and quality of its forest habitat are in decline. Threats to this habitat include forest clearance, mostly for housing and agriculture. Vulnerable Species: Snaggletooth Shark The snaggletooth shark ( Hemipristis elongatus ) is found in the tropical, coastal waters of the Indian and Pacific Oceans. Its area of occupancy is enormous, from Southeast Africa to the Philippines, and from China to Australia. However, the snaggletooth shark is a vulnerable species because of a severe population reduction rate. Its population has fallen more than 10 percent over 10 years. The number of these sharks is declining due to fisheries, especially in the Java Sea and Gulf of Thailand. The snaggletooth shark’s flesh, fins, and liver are considered high-quality foods. They are sold in commercial fish markets, as well as restaurants. Vulnerable Species: Galapagos Kelp Galapagos kelp ( Eisenia galapagensis ) is a type of seaweed only found near the Galapagos Islands in the Pacific Ocean. Galapagos kelp is classified as vulnerable because its population has declined more than 10 percent over 10 years. Climate change is the leading cause of decline among Galapagos kelp. El Niño, the natural weather pattern that brings unusually warm water to the Galapagos, is the leading agent of climate change in this area. Galapagos kelp is a cold-water species and does not adapt quickly to changes in water temperature.

Endangered Species 1) Population reduction rate A species is classified as endangered when its population has declined between 50 and 70 percent. This decline is measured over 10 years or three generations of the species, whichever is longer. A species is classified as endangered when its population has declined at least 70 percent and the cause of the decline is known. A species is also classified as endangered when its population has declined at least 50 percent and the cause of the decline is not known. 2) Geographic range An endangered species’ extent of occurrence is less than 5,000 square kilometers (1,930 square miles). An endangered species’ area of occupancy is less than 500 square kilometers (193 square miles). 3) Population size A species is classified as endangered when there are fewer than 2,500 mature individuals. When a species population declines by at least 20 percent within five years or two generations, it is also classified as endangered. 4) Population restrictions A species is classified as endangered when its population is restricted to less than 250 mature individuals. When a species’ population is this low, its area of occupancy is not considered. 5) Probability of extinction in the wild is at least 20 percent within 20 years or five generations, whichever is longer.

Endangered Species: Scimitar -horned Oryx The scimitar-horned oryx ( Oryx dammah ) is a species of antelope with long horns. Its range extends across northern Africa. Previously, the scimitar-horned oryx was listed as extinct in the wild because the last confirmed sighting of one was in 1988. However, the first group of scimitar-horned oryx was released back into the wild in Chad, in August 2016, and the population is growing. Overhunting and habitat loss, including competition with domestic livestock , are the main reasons for the decline of the oryx’s wild population. Captive herds are now kept in protected areas of Tunisia, Senegal, and Morocco. Scimitar-horned oryxes are also found in many zoos . Critically Endangered Species 1) Population reduction rate A critically endangered species’ population has declined between 80 and 90 percent. This decline is measured over 10 years or three generations of the species, whichever is longer. A species is classified as critically endangered when its population has declined at least 90 percent and the cause of the decline is known. A species is also classified as endangered when its population has declined at least 80 percent and the cause of the decline is not known. 2) Geographic range A critically endangered species’ extent of occurrence is less than 100 square kilometers (39 square miles). A critically endangered species’ area of occupancy is estimated to be less than 10 square kilometers (4 square miles). 3) Population size A species is classified as critically endangered when there are fewer than 250 mature individuals. A species is also classified as critically endangered when the number of mature individuals declines by at least 25 percent within three years or one generation, whichever is longer. 4) Population restrictions A species is classified as critically endangered when its population is restricted to less than 50 mature individuals. When a species’ population is this low, its area of occupancy is not considered. 5) Probability of extinction in the wild is at least 50 percent within 10 years or three generations, whichever is longer. Critically Endangered Species: Bolivian Chinchilla Rat The Bolivian chinchilla rat ( Abrocoma boliviensis ) is a rodent found in a small section of the Santa Cruz region of Bolivia. It is critically endangered because its extent of occurrence is less than 100 square kilometers (39 square miles). The major threat to this species is loss of its cloud forest habitat. People are clearing forests to create cattle pastures .

Critically Endangered Species: Transcaucasian Racerunner The Transcaucasian racerunner ( Eremias pleskei ) is a lizard found on the Armenian Plateau , located in Armenia, Azerbaijan, Iran, and Turkey. The Transcaucasian racerunner is a critically endangered species because of a huge population decline, estimated at more than 80 percent during the past 10 years. Threats to this species include the salination , or increased saltiness, of soil . Fertilizers used for agricultural development seep into the soil, increasing its saltiness. Racerunners live in and among the rocks and soil, and cannot adapt to the increased salt in their food and shelter. The racerunner is also losing habitat as people create trash dumps on their area of occupancy. Critically Endangered Species: White Ferula Mushroom The white ferula mushroom ( Pleurotus nebrodensis ) is a critically endangered species of fungus. The mushroom is critically endangered because its extent of occurrence is less than 100 square kilometers (39 square miles). It is only found in the northern part of the Italian island of Sicily, in the Mediterranean Sea. The leading threats to white ferula mushrooms are loss of habitat and overharvesting. White ferula mushrooms are a gourmet food item. Farmers and amateur mushroom hunters harvest the fungus for food and profit. The mushrooms can be sold for up to $100 per kilogram (2.2 pounds). Extinct in the Wild A species is extinct in the wild when it only survives in cultivation (plants), in captivity (animals), or as a population well outside its established range. A species may be listed as extinct in the wild only after years of surveys have failed to record an individual in its native or expected habitat.

Extinct in the Wild: Monut Kaala Cyanea The Mount Kaala cyanea ( Cyanea superba ) is a large, flowering tree native to the island of Oahu, in the U.S. state of Hawai‘i. The Mount Kaala cyanea has large, broad leaves and fleshy fruit. The tree is extinct in the wild largely because of invasive species. Non-native plants crowded the cyanea out of its habitat, and non-native animals such as pigs, rats, and slugs ate its fruit more quickly than it could reproduce. Mount Kaala cyanea trees survive in tropical nurseries and botanical gardens . Many botanists and conservationists look forward to establishing a new population in the wild. Extinct A species is extinct when there is no reasonable doubt that the last remaining individual of that species has died. Extinct: Cuban Macaw The Cuban macaw ( Ara tricolor ) was a tropical parrot native to Cuba and a small Cuban island, Isla de la Juventud. Hunting and collecting the birds for pets led to the bird’s extinction. The last specimen of the Cuban macaw was collected in 1864. Extinct: Ridley’s Stick Insect Ridley’s stick insect ( Pseudobactricia ridleyi ) was native to the tropical jungle of the island of Singapore. This insect, whose long, segmented body resembled a tree limb, is only known through a single specimen, collected more than 100 years ago. During the 20th century, Singapore experienced rapid development. Almost the entire jungle was cleared, depriving the insect of its habitat.

Endangered Species and People When a species is classified as endangered, governments and international organizations can work to protect it. Laws may limit hunting and destruction of the species’ habitat. Individuals and organizations that break these laws may face huge fines. Because of such actions, many species have recovered from their endangered status. The brown pelican ( Pelecanus occidentalis ) was taken off the endangered species list in 2009, for instance. This seabird is native to the coasts of North America and South America, as well as the islands of the Caribbean Sea. It is the state bird of the U.S. state of Louisiana. In 1970, the number of brown pelicans in the wild was estimated at 10,000. The bird was classified as vulnerable. During the 1970s and 1980s, governments and conservation groups worked to help the brown pelican recover. Young chicks were reared in hatching sites, then released into the wild. Human access to nesting sites was severely restricted. The pesticide DDT , which damaged the eggs of the brown pelican, was banned. During the 1980s, the number of brown pelicans soared. In 1988, the IUCN “delisted” the brown pelican. The bird, whose population is now in the hundreds of thousands, is now in the category of least concern.

Convention on Biological Diversity The Convention on Biological Diversity is an international treaty to sustain and protect the diversity of life on Earth. This includes conservation, sustainability, and sharing the benefits of genetic research and resources. The Convention on Biological Diversity has adopted the IUCN Red List of endangered species in order to monitor and research species' population and habitats. Three nations have not ratified the Convention on Biological Diversity: Andorra, the Holy See (Vatican), and the United States.

Lonesome George Lonesome George was the only living member of the Pinta Island tortoise ( Chelonoidis abingdoni ) known to exist. The Pinta Island tortoise was only found on Pinta, one of the Galapagos Islands. The Charles Darwin Research Station, a scientific facility in the Galapagos, offered a $10,000 reward to any zoo or individual for locating a single Pinta Island tortoise female. On June 25, 2012, Lonesome George died, leaving one more extinct species in the world.

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Pair of rare Amur tiger cubs debuting at Minnesota Zoo are raising hopes for the endangered species

APPLE VALLEY, Minn. (AP) — A pair of rare Amur tiger cubs are making their public debut at the Minnesota Zoo, raising hopes for preserving an endangered species that’s native to far eastern Russia and northern China.

Andrei and Amaliya got to venture outside and feel the grass of their new home under their paws Wednesday for the first time since their 12-year-old mother, Dari, gave birth on May 23.

“They’ve done quite well since then,” zoologist Trista Fischer said. “We’ve monitored them very closely. Dari’s been fantastic. She’s provided outstanding maternal care. And so today we’ve reached the point where they’re fully vaccinated and they’re now about 40 to 45 pounds (18-20 kilograms).”

Scientists estimate the Amur tiger population is just around 400 to 500 in the wild. They were near the brink of extinction in the 1930s and 1940s but have recovered somewhat since then. It’s tricky to breed them, and around one in four Amur cubs don’t make it to adulthood, whether it’s in the wild or in captivity, she said. Poachers are another major threat.

But the Minnesota Zoo, located in the Minneapolis suburb of Apple Valley, has a long history of conserving tigers. Its Amur tigers have produced 57 cubs, 46 of which survived for at least 30 days. Of those 46, 21 have gone on to produce litters of their own, amounting to another 86 cubs. The births of Andrei and Amaliya raised the zoo’s population to seven Amur tigers, including their sire, Luka.

Fischer is the leading coordinator for the Tiger Species Survival Plan, a breeding program in the United States with facilities in other countries that works on a global level to preserve the big cats. The plan manages three groups of tigers: Sumatran, Malayan and Amur.

“This litter is so valuable to the population right now,” she explained, saying the genetic diversity of heathy tigers in human care could someday be used to help support populations in the wild.

Zoo spokesperson Zach Nugent said the cubs will remain housed together with their mom for about 18 months, before Andrei, the male, is moved to separate housing, around the same time a male cub in the wild would start venturing out on his own. Amaliya, the female, may spend a little more time with Dari, up to 24 months. Then Fischer will determine whether either cub should be bred, and potentially moved for that to another accredited zoo, which typically happens after the cubs are 2 years old.

“Aww, I love when they get their little Yoda ears,” Fischer said referring to the pointy ears of the Star Wars character as she watched Amaliya and Andrei explore the new terrain of their enclosure. She said it was an emotional, exciting and proud moment for her and her team.

“Our work’s not over, but all that work so far is really paying off in how well that these cubs are acclimating to a new surrounding, pretty much immediately,” she said as the little tigers roamed outside with their mother. “They’re showing a lot of resiliency, which is something that we work hard for in human care. We want these animals to have a lot of confidence and be able to adapt to new environments just as they’re doing today.”

Karnowski reported from Minneapolis.

Copyright 2024 The Associated Press. All rights reserved.

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Awareness programme on endangered species organised for fishermen and other stakeholders

Published - September 10, 2024 09:39 pm IST - VISAKHAPATNAM

One of the fishermen, who had done exemplary service for the rescue of endangered marine species, being felicitated by the officials, at an awareness programme, organised by the CMFRI in Visakhapatnam on Tuesday. | Photo Credit: BY ARRANGEMENT

An awareness programme on the conservation of marine protected species such as mammals (whales, porpoises, dugongs and dolphins), reptiles (sea turtles and snakes), and endangered, threatened and protected (ETP) was organised by the Visakhapatnam Regional Centre of ICAR- Central Marine Fisheries Research Institute (CMFRI) at the fishing harbour, here, on Tuesday.

The objective of the programme was to enhance understanding and engagement of coastal communities and stakeholders in conservation, protection and restoration of vital marine ecosystems and its constituent protected species.

Stakeholders in the sector, fishermen association and trade leaders, various department officials working in the related sectors and Wildlife Authorities and officials from the Marine Police, maritime, Port, Coast Guard, Navy and NGOs in the field participated in the programme.

According to the experts, promoting awareness and support for endangered species, implementing effective rescue and alert systems, and fostering a network of conservation leaders could significantly accelerate the efforts to protect wildlife.

Chief Conservator of Forests Srikanthanatha Reddy, Visakhapatnam, participated as the chief guest. Deputy Conservator of Forests G. Mangamma and retired DFO Janaki Rao spoke .

The meeting discussed the impacts of coastal pollution (plastics/chemicals/urban wastes/industrial and thermal effluents), certain fishing practices, increased navigational traffic, and other anthropogenic interventions such as sounds, lights, coastal constructions and mining. The discussions also brought some recommendations, including rewarding incentives or delivering compensatory loss reimbursing equivalents upon a recovery effort to bring in more volunteers and bringing in more awareness and support for mass involvements.

During the programme, 25 active fishermen (rescuers) from Srikakulam, Vizianagaram and Visakhapatnam districts were felicitated for the exemplary services in rescue of different endangered, threatened and protected marine species in the coast of Andhra Pradesh during the last few years and were honoured with medals and certificates.

The officials from different government institutions such as CIFT, MPEDA, NETFISH, FSI, CIFNET, NIFPHAT, Department of Fisheries AP, Department of Forest, A.P., and the Department of Marine Living Resources, Andhra University, attended the programme.

V. Laxman Rao, president, and members of the AP Mechanised Fishing Boat Operators Association, as well as representatives of the Dolphin Boat Owners Association, Visakhapatnam, also participated in the programme.

Joe K. Kizhakudan, Principal Scientist and Head of ICAR-CMFRI, Visakhapatnam, and Pralaya Ranjan Behera, Senior Scientist and Principal Investigator of the project, spoke.

Pamphlets giving information on protected marine species of Andhra Pradesh were distributed to the fishermen.

Published - September 10, 2024 09:39 pm IST

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The Biden administration is taking steps to eliminate protections for gray wolves

The Biden administration has asked an appeals court to revive a Trump-era rule that lifted remaining Endangered Species Act protections for gray wolves in the U.S. If successful, the move would put the predators under states’ oversight and would allow ...

BILLINGS, Mont. -- The Biden administration on Friday asked an appeals court to revive a Trump-era rule that lifted remaining Endangered Species Act protections for gray wolves in the U.S.

If successful, the move would put the predators under state oversight nationwide and open the door for hunting to resume in the Great Lakes region after it was halted two years ago under court order.

Environmentalists had successfully sued when protections for wolves were lifted in former President Donald Trump’s final days in office.

Friday’s filing with the 9th U.S. District Court of Appeals was President Joe Biden administration’s first explicit step to revive that rule. Protections will remain in place pending the court’s decision.

The court filing follows years of political acrimony as wolves have repopulated some areas of the western U.S., sometimes attacking livestock and eating deer, elk and other big game.

Environmental groups want that expansion to continue since wolves still occupy only a fraction of their historic range.

Attempts to lift or reduce protections for wolves date to the first term of former President George W. Bush more than two decades ago and have continued with each subsequent administration.

They once roamed most of North America but were widely decimated by the mid-1900s in government-sponsored trapping and poisoning campaigns. Gray wolves were granted federal protections in 1974.

Each time the U.S. Fish and Wildlife Service declares them recovered, the agency is challenged in court. Wolves in different parts of the U.S. lost and regained protections multiple times in recent years.

“The U.S. Fish and Wildlife Service is focused on a concept of recovery that allows wolves to thrive on the landscape while respecting those who work and live in places that support them,” agency spokesperson Vanessa Kauffman said.

The administration is on the same side in the case as livestock and hunting groups, the National Rifle Association and Republican-led Utah.

It’s opposed by the Sierra Club, Center for Biological Diversity, Humane Society of the United States and other groups.

“While wolves are protected, they do very well, and when they lose protections, that recovery backslides,” said Collette Adkins with the Center for Biological Diversity. “We won for good reason at the district court.”

She said she was “saddened” officials were trying to reinstate the Trump administration's rule.

Efforts to restore wolves to date have been limited to a handful of regions. Federal officials earlier this year agreed to develop a first-ever national recovery plan, by December 2025, under a settlement in a separate lawsuit.

Kauffman declined to say whether that national plan would still be pursued if the government prevails in the 9th Circuit case.

But attorneys suggested in Friday's court filing that the government is ready to move on from gray wolf recovery, now that the species is no longer in danger of extinction.

“The ESA (Endangered Species Act) is clear: its goal is to prevent extinction, not to restore species to their pre-western settlement numbers and range," U.S. Department of Justice attorneys wrote.

The 2022 ruling that restored protections said wildlife officials had failed to show wolf populations could be sustained in the Midwest and portions of the West. Officials also didn’t adequately consider threats to wolves outside those core areas, said U.S. District Judge Jeffrey White in California.

The Great Lakes region has more than 4,000 wolves. More than 2,000 wolves occupy states in the Rocky Mountains and Pacific Northwest.

Congress circumvented the courts in 2011 and stripped federal safeguards in the northern U.S. Rocky Mountains. Thousands of wolves have since been killed in Montana, Idaho and Wyoming.

Lawmakers have continued to press for state control in the western Great Lakes region. When those states gained jurisdiction over wolves briefly under the Trump rule, trappers and hunters using hounds blew past harvest goals in Wisconsin and killed almost twice as many as planned.

Michigan and Minnesota have previously held hunts but not in recent years.

Wolves are present but no public hunting is allowed in states including Washington, Oregon, California and Colorado. They’ve never been protected in Alaska, where tens of thousands of the animals live.

The Biden administration last year rejected requests from conservation groups to restore protections for gray wolves across the northern Rockies. That decision, too, has been challenged.

State lawmakers in that region, which includes Yellowstone National Park and vast areas of wilderness, are intent on culling more wolf packs . But federal officials determined the predators were not in danger of being wiped out entirely under the states’ loosened hunting rules.

The U.S. also is home to small, struggling populations of red wolves in the mid-Atlantic region and Mexican wolves in the Southwest. Those populations are both protected as endangered.

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Pair of rare Amur tiger cubs debuting at Minnesota Zoo are raising hopes for the endangered species

A pair of rare Amur tiger cubs are making their public debut at the Minnesota Zoo, raising hopes for preserving an endangered species that’s native to far eastern Russia and northern China. (AP video: Mark Vancleave)

Three-month-old Amur tiger cubs Amaliya explores her outdoor enclosure for the first time with their mother Dari at the Minnesota Zoo in Apple Valley, Minn. on Wednesday, Sept. 11, 2024. (AP photo/Mark Vancleave)

Three-month-old Amur tiger cubs Amaliya and Andrei explored their outdoor enclosure for the first time with their mother Dari at the Minnesota Zoo in Apple Valley, Minn. on Wednesday, Sept. 11, 2024. (AP photo/Mark Vancleave)

Three-month-old Amur tiger cubs Amaliya explores her outdoor enclosure for the first time with her mother Dari at the Minnesota Zoo in Apple Valley, Minn. on Wednesday, Sept. 11, 2024. (AP photo/Mark Vancleave)

• Copy Link copied

APPLE VALLEY, Minn. (AP) — A pair of rare Amur tiger cubs are making their public debut at the Minnesota Zoo, raising hopes for preserving an endangered species that’s native to far eastern Russia and northern China.

Andrei and Amaliya got to venture outside and feel the grass of their new home under their paws Wednesday for the first time since their 12-year-old mother, Dari, gave birth on May 23.

“They’ve done quite well since then,” zoologist Trista Fischer said. “We’ve monitored them very closely. Dari’s been fantastic. She’s provided outstanding maternal care. And so today we’ve reached the point where they’re fully vaccinated and they’re now about 40 to 45 pounds (18-20 kilograms).”

Scientists estimate the Amur tiger population is just around 400 to 500 in the wild. They were near the brink of extinction in the 1930s and 1940s but have recovered somewhat since then. It’s tricky to breed them, and around one in four Amur cubs don’t make it to adulthood, whether it’s in the wild or in captivity, she said. Poachers are another major threat.

But the Minnesota Zoo, located in the Minneapolis suburb of Apple Valley, has a long history of conserving tigers. Its Amur tigers have produced 57 cubs, 46 of which survived for at least 30 days. Of those 46, 21 have gone on to produce litters of their own, amounting to another 86 cubs. The births of Andrei and Amaliya raised the zoo’s population to seven Amur tigers, including their sire, Luka.

Fischer is the leading coordinator for the Tiger Species Survival Plan, a breeding program in the United States with facilities in other countries that works on a global level to preserve the big cats. The plan manages three groups of tigers: Sumatran, Malayan and Amur.

“This litter is so valuable to the population right now,” she explained, saying the genetic diversity of heathy tigers in human care could someday be used to help support populations in the wild.

Zoo spokesperson Zach Nugent said the cubs will remain housed together with their mom for about 18 months, before Andrei, the male, is moved to separate housing, around the same time a male cub in the wild would start venturing out on his own. Amaliya, the female, may spend a little more time with Dari, up to 24 months. Then Fischer will determine whether either cub should be bred, and potentially moved for that to another accredited zoo, which typically happens after the cubs are 2 years old.

“Aww, I love when they get their little Yoda ears,” Fischer said referring to the pointy ears of the Star Wars character as she watched Amaliya and Andrei explore the new terrain of their enclosure. She said it was an emotional, exciting and proud moment for her and her team.

“Our work’s not over, but all that work so far is really paying off in how well that these cubs are acclimating to a new surrounding, pretty much immediately,” she said as the little tigers roamed outside with their mother. “They’re showing a lot of resiliency, which is something that we work hard for in human care. We want these animals to have a lot of confidence and be able to adapt to new environments just as they’re doing today.”

Karnowski reported from Minneapolis.