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Reptile research shows new avenues and old challenges for extinction risk modelling

* E-mail: [email protected]

Affiliation Department of Biology and Biotechnologies, Sapienza University of Rome, Rome, Italy

Moreno Di Marco

Published: July 11, 2022

https://doi.org/10.1371/journal.pbio.3001719
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In a new PLOS Biology paper, de Oliveira Caetano and colleagues presented an innovative method to estimate extinction risk in reptile species worldwide. The method shows a promising avenue to support Red List assessment, alongside some well-known challenges.

Citation: Di Marco M (2022) Reptile research shows new avenues and old challenges for extinction risk modelling. PLoS Biol 20(7): e3001719. https://doi.org/10.1371/journal.pbio.3001719

Copyright: © 2022 Moreno Di Marco. 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.

Funding: MDM acknowledges support from the MUR Rita Levi Montalcini program. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing interests: The author has declared that no competing interests exist.

Human-induced rates of species extinction largely surpass the background rates registered from the fossil record [ 1 ], and global monitoring of extinction risk is essential to track progresses towards sustainable development. The Red List of the International Union for the Conservation of Nature (IUCN; hereafter “Red List”) is the global authority that manages data on species extinction risk, now including over 140,000 assessed species. Yet, while the taxonomic coverage of the Red List has rapidly grown, a parallel increase in resources for update (i.e., periodic reassessment) has not followed [ 2 ]. Limited reassessment efforts means that the Red List is constantly facing a risk of becoming outdated, with many species (ca. 20% at the time of writing) having an assessment older than 10 years and possibly undergoing undetected decline. Under rapidly accelerating human pressure, there is a clear need to make the global monitoring of extinction risk more effective.

Many works have proposed approaches that might support extinction risk monitoring [ 3 ] using automated estimates of Red List parameters, e.g., population decline inferred from satellite-borne estimates of deforestation rates [ 4 ], or directly modelling Red List categories (or aggregation of categories) from environmental and life history variables [ 5 ]. Yet, very few of these approaches have fed into the Red List process, generating a research-implementation gap [ 3 ]. For example, most extinction risk modelling exercise do not reflect the process of Red List assessment (including its required parameters and guidelines), which makes it difficult to incorporate modelling outputs in the Red List. At the same time, there is often an implementation barrier even for potentially relevant methods, due to limited technical capacity by (and limited training offered to) assessors. However, recent research on reptiles shows a promising avenue to advance this debate.

In a new PLOS Biology paper, de Oliveira Caetano and colleagues [ 6 ] presented an innovative machine learning analysis to estimate the extinction risk of 4,369 reptile species that were unassessed or data deficient in the Red List. Meanwhile, in a recent Nature paper, Cox and colleagues [ 7 ] presented the results of the Global Reptile assessment, including extinction risk categories for ca. 85% of the 10,196 reptile species in the Red List (the rest being data deficient). Reptiles are a diverse group which represent a perfect example of the “update or outdate” conundrum in the Red List, as their assessment required nearly 50 workshops and 15 years to complete [ 7 ]. At the same time, enough data on reptile distribution and life history are now available [ 8 ] to attempt large-scale extinction risk modelling for the group, indicating that it might be time to “bridge” the research-implementation gap [ 3 ].

The model presented in [ 6 ] was 84% accurate in predicting Red List categories during cross-validation and found unassessed species to face higher risk compared to assessed species (27% versus 21% species threatened with extinction). The model’s performance was higher compared to previous similar exercises, albeit prediction accuracy for certain categories (e.g., near threatened) was substantially lower than others (e.g., least concern). The recent completion of nearly all reptile assessments in the Red List [ 9 ] allows to compare the model’s performance measured on the training set of originally assessed species (i.e., “model interpolation”) versus the performance measured on newly assessed species not used for model training (i.e., “model extrapolation”) ( Fig 1 ).

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The bar plots report the contingency distribution between predicted Red List categories (y-axis, prediction) and assessed categories (x-axis, observation). Plot (a) reports the contingency between assessed versus predicted categories for 6,520 species used to train the automated assessment model in [ 6 ]. Plot (b) reports the contingency between assessed versus predicted categories for 1,463 species that were considered unassessed and not used for model training in [ 6 ] and were only assigned a Red List category in 2021 [ 9 ]. For this latter comparison, I only selected species having precise taxonomic correspondence with the latest release of the IUCN Red List database and being assigned a category of risk (see S1 Table ), as follows: CR, critically endangered; EN, endangered; LC, least concern; NT, near threatened; VU, vulnerable.

https://doi.org/10.1371/journal.pbio.3001719.g001

The automated assessment model in [ 6 ] showed high accuracy both in the interpolation and extrapolation of least concern species: 92% of the species newly assessed as least concern were correctly predicted by the model. This reflects the ability of automated methods to separate least concern species from the rest, which is a promising implementation for facilitating periodic reassessments [ 10 ]. However, the model’s ability to extrapolate near threatened and threatened categories was substantially lower than the ability to interpolate those categories. Less than 30% of the newly assessed species in each of these categories were correctly predicted by the model: In most cases, these species were predicted as least concern.

The mismatch between predicted versus assessed categories during model extrapolation can have multiple causes. For 18% newly assessed species, the model predicted a lower category of risk than what Red List assessors have then assigned. This might happen because assessors have access to information on threats that are not explicitly accounted for in the model (harvesting, pathogens, invasive species, etc.). Instead, for 10% of species, the model predicted a higher category of risk than that assigned by Red List assessors. This might be related to the compound mechanistic nature of Red List criteria, which require a combination of parameters that models are typically unable to account for (e.g., restricted distribution AND severe fragmentation AND continuing decline). Importantly, however, the 2 works are based on different sources of species’ distribution maps, which can lead to a discrepancy in the measure of environmental and spatial variables (e.g., extent of occurrence) for the same species. If the distribution maps of newly assessed species differ substantially between the GARD dataset [ 8 ] and the Red List dataset [ 9 ], the mismatch in category prediction can be simply an outcome of different underlying data. This calls for a better homogenisation of spatial data used for extinction risk modelling and assessment purposes. Of course, there is also the possibility that some of the new assessments are incorrect, as Red List assessors did not have sufficient information to determine a species’ status while the model was able to use ancillary information. In this case, an indication of mismatch between predicted versus assessed category can be used to inform future reassessments [ 3 ].

Regardless of prediction performance, both recent works [ 6 , 7 ] highlight the difficulty to properly account for the effect of climate change. Cox and colleagues acknowledged the limited consideration of climate vulnerability in reptile Red List assessments [ 7 ], as the proportion of threatened species at risk from climate change (11%) was much lower than that of birds (30%). This likely indicates lower knowledge rather than lower vulnerability, considering that reptiles are ectotherms with limited climatic tolerance and dispersal ability [ 11 ]. Possibly because of this knowledge gap, climatic variables had limited predictive importance in the automated assessment model in [ 6 ]. As climate change accelerates, it is paramount that climate risk for groups such as reptiles and amphibians is consistently and customarily assessed in the Red List [ 12 ].

The recent publication of an innovative extinction risk model, alongside the complete Red List assessment of reptile species, shows promising avenues but also some well-known challenges for technological applications in the Red List. Automated assessment models can help Red List assessors by (i) quickly identifying species that are least concern and not in need of immediate conservation attention; (ii) pinpointing species that might be in need of reassessment (i.e., those with a mismatch between predicted versus assessed category); and (iii) investigate any significant bias in the assessment process (e.g., associated with differential application of the Red List guidelines by assessors). However, for these methods to be effective, it is important that model outputs are shared with assessors and any feedback is iteratively used to improve model’s structure, interpretation, and validation.

Supporting information

S1 table. list of reptile species considered unassessed (and not used for model training) in the work of de caetano oliveira and colleagues and subsequently assigned a red list category in 2021..

The list only includes species having precise taxonomic correspondence with the latest release of the IUCN Red List database and being assigned a category of risk.

https://doi.org/10.1371/journal.pbio.3001719.s001

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9. IUCN. The IUCN Red List of Threatened Species. Version 2021–3. 2021 [cited 2022 May 10]. Available from: https://www.iucnredlist.org .

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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 ).

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Extinct or possibly extinct listed species by taxonomic group.

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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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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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The sixth extinction crisis: Loss of animal populations and species

2010, Journal of Cosmology

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Andres Garcia

Proceedings of the National Academy of Sciences

Gerardo Ceballos

Significance The strong focus on species extinctions, a critical aspect of the contemporary pulse of biological extinction, leads to a common misimpression that Earth’s biota is not immediately threatened, just slowly entering an episode of major biodiversity loss. This view overlooks the current trends of population declines and extinctions. Using a sample of 27,600 terrestrial vertebrate species, and a more detailed analysis of 177 mammal species, we show the extremely high degree of population decay in vertebrates, even in common “species of low concern.” Dwindling population sizes and range shrinkages amount to a massive anthropogenic erosion of biodiversity and of the ecosystem services essential to civilization. This “biological annihilation” underlines the seriousness for humanity of Earth’s ongoing sixth mass extinction event.

Victor Nazarevich

The number of species becoming extinct has drawn a significant deal of attention from scientists and non-scientists alike. This research reviews recent literature citing evidence for the impact humans have had on our planet and how our biological systems are affected in both known species of flora and fauna as well as unknown species of flora and fauna, the latter lacking documentation as well as sightings by humans. Theoretical research is derived from previous research investigating the impacts of humankind's use of the land as well as population increases. Though there are many different definitions of what a mass extinction is and gradations of extinction intensity, a conservative approach is used to assess the seriousness of the current ongoing extinction crisis, setting the highest level of recognition for mass extinction, in extreme diversity loss associated with the Big Five extinction events (Barnosky, 2011). Understanding the relationship between extinction and functional diversity over time will be critical for making conservation work (Boyer & Jetz, 2014). If another mass extinction is allowed to progress, it would mean the end of biodiversity as we know it and would also mean that greater pressure would be placed on both humans and flora and fauna to survive in a world completely changed by the Anthropocene. Over the course of 8,000-10,000 years, humans grew in population and changed the landscape

Biodiversity and Conservation

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The ongoing sixth mass species extinction is the result of the destruction of component populations leading to eventual extirpation of entire species. Populations and species extinctions have severe implications for society through the degradation of ecosystem services. Here we assess the extinction crisis from a different perspective. We examine 29,400 species of terrestrial vertebrates, and determine which are on the brink of extinction because they have fewer than 1,000 individuals. There are 515 species on the brink (1.7% of the evaluated vertebrates). Around 94% of the populations of 77 mammal and bird species on the brink have been lost in the last century. Assuming all species on the brink have similar trends, more than 237,000 populations of those species have vanished since 1900. We conclude the human-caused sixth mass extinction is likely accelerating for several reasons. First, many of the species that have been driven to the brink will likely become extinct soon. Second,...

The human race faces many global to local challenges in the near future. Among these are massive biodiversity losses. The 2012 IUCN/SSC Red List reported evaluations of *56 % of all vertebrates. This included 97 % of amphibians, mammals, birds, cartilaginous fishes, and hagfishes. It also contained evaluations of *50 % of lampreys, *38 % of reptiles, and *29 % of bony fishes. A cursory examination of extinction magnitudes does not immediately reveal the severity of current biodiversity losses because the extinctions we see today have happened in such a short time compared to earlier events in the fossil record. So, we still must ask how current losses of species compare to losses in mass extinctions from the geological past. The most recent and best understood mass extinction is the Cretaceous terminal extinction which ends at the Cretaceous– Paleogene (K–Pg) border, 65 MYA. This event had massive losses of biodiversity (*17 % of families, [50 % of genera, and [70 % of species) and exterminated the dinosaurs. Extinction estimates for non-dinosaurian vertebrates at the K–Pg boundary range from 36 to 43 %. However, there remains much uncertainty regarding the completeness, preservation rates, and extinction magnitudes of the different classes of vertebrates. Fuzzy arithmetic was used to compare recent vertebrate extinction reported in the 2012 IUCN/SSC Red List with biodiversity losses at the end of K–Pg. Comparisons followed 16 different approaches to data compilation and 288 separate calculations. I tabulated the number of extant and extinct species (extinct ? extinct in the wild), extant island endemics, data deficient species, and so-called impaired species [species with IUCN/SSC Red List designations from vulnerable (VU) to critically endangered (CR)]. Species that went extinct since 1500 and since 1980 were tabulated. Vertebrate extinction moved forward 24–85 times faster since 1500 than during the Cretaceous mass extinction. The magnitude of extinction has exploded since 1980, with losses about 71–297 times larger than during the K–Pg event. If species identified by the IUCN/SSC as critically endangered through vulnerable, and those that are data deficient are assumed extinct by geological standards, then vertebrate extinction approaches 8900–18,500 times the magnitude during that mass extinction. These extreme values and the great speed with which vertebrate biodiversity is being decimated are comparable to the devastation of previous extinction events. If recent levels of extinction were to continue, the magnitude is sufficient to drive these groups extinct in less than a century.

niles eldredge

There is little doubt left in the minds of professional biologists that Earth is currently faced with a mounting loss of species that threatens to rival the five great mass extinctions of the geological past. As long ago as 1993, Harvard biologist E.O. Wilson estimated that Earth is currently losing something on the order of 30,000 species per year — which breaks down to the even more daunting statistic of some three species per hour. Some biologists have begun to feel that this biodiversity crisis — this “Sixth Extinction” — is even more severe, and more imminent, than Wilson had supposed.

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Extinction of species has been a recurrent phenomenon in the history of our planet, but it was generally outweighed in the course of quite a long geological time by the appearance of new species, except, especially, for the five geologically short times when the so-called “Big Five” mass extinctions occurred. Could the current decline in biodiversity be considered as a signal of an ongoing, human-driven sixth mass extinction? This note briefly examines some issues related to: (i) The hypothesized current extinction rate and the magnitude of contemporary global biodiversity loss; (ii) the challenges of comparing them to the background extinction rate and the magnitude of the past Big Five mass extinction events; (iii) briefly considering the effects of the main anthropogenic stressors on ecosystems, including the risk of the emergence of pandemic diseases. A comparison between the Pleistocene fauna dynamics with the present defaunation process and the cascading effects of recent anth...

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Can We Save Every Species from Extinction?

The Endangered Species Act requires that every U.S. plant and animal be saved from extinction, but after 50 years, we have to do much more to prevent a biodiversity crisis

By Robert Kunzig

Light and dark brown striped fish with iridescent fins shown against a black background.

Snail Darter Percina tanasi. Listed as Endangered: 1975. Status: Delisted in 2022.

A Bald Eagle disappeared into the trees on the far bank of the Tennessee River just as the two researchers at the bow of our modest motorboat began hauling in the trawl net. Eagles have rebounded so well that it's unusual not to see one here these days, Warren Stiles of the U.S. Fish and Wildlife Service told me as the net got closer. On an almost cloudless spring morning in the 50th year of the Endangered Species Act, only a third of a mile downstream from the Tennessee Valley Authority's big Nickajack Dam, we were searching for one of the ESA's more notorious beneficiaries: the Snail Darter. A few months earlier Stiles and the FWS had decided that, like the Bald Eagle, the little fish no longer belonged on the ESA's endangered species list. We were hoping to catch the first nonendangered specimen.

Dave Matthews, a TVA biologist, helped Stiles empty the trawl. Bits of wood and rock spilled onto the deck, along with a Common Logperch maybe six inches long. So did an even smaller fish; a hair over two inches, it had alternating vertical bands of dark and light brown, each flecked with the other color, a pattern that would have made it hard to see against the gravelly river bottom. It was a Snail Darter in its second year, Matthews said, not yet full-grown.

Everybody loves a Bald Eagle. There is much less consensus about the Snail Darter. Yet it epitomizes the main controversy still swirling around the ESA, signed into law on December 28, 1973, by President Richard Nixon: Can we save all the obscure species of this world, and should we even try, if they get in the way of human imperatives? The TVA didn't think so in the 1970s, when the plight of the Snail Darter—an early entry on the endangered species list—temporarily stopped the agency from completing a huge dam. When the U.S. attorney general argued the TVA's case before the Supreme Court with the aim of sidestepping the law, he waved a jar that held a dead, preserved Snail Darter in front of the nine judges in black robes, seeking to convey its insignificance.

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Now I was looking at a living specimen. It darted around the bottom of a white bucket, bonking its nose against the side and delicately fluttering the translucent fins that swept back toward its tail.

“It's kind of cute,” I said.

Matthews laughed and slapped me on the shoulder. “I like this guy!” he said. “Most people are like, ‘Really? That's it?’ ” He took a picture of the fish and clipped a sliver off its tail fin for DNA analysis but left it otherwise unharmed. Then he had me pour it back into the river. The next trawl, a few miles downstream, brought up seven more specimens.

In the late 1970s the Snail Darter seemed confined to a single stretch of a single tributary of the Tennessee River, the Little Tennessee, and to be doomed by the TVA's ill-considered Tellico Dam, which was being built on the tributary. The first step on its twisting path to recovery came in 1978, when the U.S. Supreme Court ruled, surprisingly, that the ESA gave the darter priority even over an almost finished dam. “It was when the government stood up and said, ‘Every species matters, and we meant it when we said we're going to protect every species under the Endangered Species Act,’” says Tierra Curry, a senior scientist at the Center for Biological Diversity.

Bald Eagle Haliaeetus leucocephalus. Listed as Endangered: 1967. Status: Delisted in 2007. Credit: © Joel Sartore/National Geographic Photo Ark

Today the Snail Darter can be found along 400 miles of the river's main stem and multiple tributaries. ESA enforcement has saved dozens of other species from extinction. Bald Eagles, American Alligators and Peregrine Falcons are just a few of the roughly 60 species that had recovered enough to be “delisted” by late 2023.

And yet the U.S., like the planet as a whole, faces a growing biodiversity crisis. Less than 6 percent of the animals and plants ever placed on the list have been delisted; many of the rest have made scant progress toward recovery. What's more, the list is far from complete: roughly a third of all vertebrates and vascular plants in the U.S. are vulnerable to extinction, says Bruce Stein, chief scientist at the National Wildlife Federation. Populations are falling even for species that aren't yet in danger. “There are a third fewer birds flying around now than in the 1970s,” Stein says. We're much less likely to see a White-throated Sparrow or a Red-winged Blackbird, for example, even though neither species is yet endangered.

The U.S. is far emptier of wildlife sights and sounds than it was 50 years ago, primarily because habitat—forests, grasslands, rivers—has been relentlessly appropriated for human purposes. The ESA was never designed to stop that trend, any more than it is equipped to deal with the next massive threat to wildlife: climate change. Nevertheless, its many proponents say, it is a powerful, foresightful law that we could implement more wisely and effectively, perhaps especially to foster stewardship among private landowners. And modest new measures, such as the Recovering America's Wildlife Act—a bill with bipartisan support—could further protect flora and fauna.

That is, if special interests don't flout the law. After the 1978 Supreme Court decision, Congress passed a special exemption to the ESA allowing the TVA to complete the Tellico Dam. The Snail Darter managed to survive because the TVA transplanted some of the fish from the Little Tennessee, because remnant populations turned up elsewhere in the Tennessee Valley, and because local rivers and streams slowly became less polluted following the 1972 Clean Water Act, which helped fish rebound.

Under pressure from people enforcing the ESA, the TVA also changed the way it managed its dams throughout the valley. It started aerating the depths of its reservoirs, in some places by injecting oxygen. It began releasing water from the dams more regularly to maintain a minimum flow that sweeps silt off the river bottom, exposing the clean gravel that Snail Darters need to lay their eggs and feed on snails. The river system “is acting more like a real river,” Matthews says. Basically, the TVA started considering the needs of wildlife, which is really what the ESA requires. “The Endangered Species Act works,” Matthews says. “With just a little bit of help, [wildlife] can recover.”

The trouble is that many animals and plants aren't getting that help—because government resources are too limited, because private landowners are alienated by the ESA instead of engaged with it, and because as a nation the U.S. has never fully committed to the ESA's essence. Instead, for half a century, the law has been one more thing that polarizes people's thinking.

I t may seem impossible today to imagine the political consensus that prevailed on environmental matters in 1973. The U.S. Senate approved the ESA unanimously, and the House passed it by a vote of 390 to 12. “Some people have referred to it as almost a statement of religion coming out of the Congress,” says Gary Frazer, who as assistant director for ecological services at the FWS has been overseeing the act's implementation for nearly 25 years.

Gopher Tortoise Gopherus polyphemus . Listed as Threatened: 1987. Status: Still threatened. Credit: ©Joel Sartore/National Geographic Photo Ark

But loss of faith began five years later with the Snail Darter case. Congresspeople who had been thinking of eagles, bears and Whooping Cranes when they passed the ESA, and had not fully appreciated the reach of the sweeping language they had approved, were disabused by the Supreme Court. It found that the legislation had created, “wisely or not ... an absolute duty to preserve all endangered species,” Chief Justice Warren E. Burger said after the Snail Darter case concluded. Even a recently discovered tiny fish had to be saved, “whatever the cost,” he wrote in the decision.

Was that wise? For both environmentalists such as Curry and many nonenvironmentalists, the answer has always been absolutely. The ESA “is the basic Bill of Rights for species other than ourselves,” says National Geographic photographer Joel Sartore, who is building a “photo ark” of every animal visible to the naked eye as a record against extinction. (He has taken studio portraits of 15,000 species so far.) But to critics, the Snail Darter decision always defied common sense. They thought it was “crazy,” says Michael Bean, a leading ESA expert, now retired from the Environmental Defense Fund. “That dichotomy of view has remained with us for the past 45 years.”

According to veteran Washington, D.C., environmental attorney Lowell E. Baier, author of a new history called The Codex of the Endangered Species Act, both the act itself and its early implementation reflected a top-down, federal “command-and-control mentality” that still breeds resentment. FWS field agents in the early days often saw themselves as combat biologists enforcing the act's prohibitions. After the Northern Spotted Owl's listing got tangled up in a bitter 1990s conflict over logging of old-growth forests in the Pacific Northwest, the FWS became more flexible in working out arrangements. “But the dark mythology of the first 20 years continues in the minds of much of America,” Baier says.

Credit: June Minju Kim ( map ); Source: David Matthews, Tennessee Valley Authority ( reference )

The law can impose real burdens on landowners. Before doing anything that might “harass” or “harm” an endangered species, including modifying its habitat, they need to get a permit from the FWS and present a “habitat conservation plan.” Prosecutions aren't common, because evidence can be elusive, but what Bean calls “the cloud of uncertainty” surrounding what landowners can and cannot do can be distressing.

Requirements the ESA places on federal agencies such as the Forest Service and the Bureau of Land Management—or on the TVA—can have large economic impacts. Section 7 of the act prohibits agencies from taking, permitting or funding any action that is likely to “jeopardize the continued existence” of a listed species. If jeopardy seems possible, the agency must consult with the FWS first (or the National Marine Fisheries Service for marine species) and seek alternative plans.

“When people talk about how the ESA stops projects, they've been talking about section 7,” says conservation biologist Jacob Malcom. The Northern Spotted Owl is a strong example: an economic analysis suggests the logging restrictions eliminated thousands of timber-industry jobs, fueling conservative arguments that the ESA harms humans and economic growth.

In recent decades, however, that view has been based “on anecdote, not evidence,” Malcom claims. At Defenders of Wildlife, where he worked until 2022 (he's now at the U.S. Department of the Interior), he and his colleagues analyzed 88,290 consultations between the FWS and other agencies from 2008 to 2015. “Zero projects were stopped,” Malcom says. His group also found that federal agencies were only rarely taking the active measures to recover a species that section 7 requires—like what the TVA did for the Snail Darter. For many listed species, the FWS does not even have recovery plans.

Endangered species also might not recover because “most species are not receiving protection until they have reached dangerously low population sizes,” according to a 2022 study by Erich K. Eberhard of Columbia University and his colleagues. Most listings occur only after the FWS has been petitioned or sued by an environmental group—often the Center for Biological Diversity, which claims credit for 742 listings. Years may go by between petition and listing, during which time the species' population dwindles. Noah Greenwald, the center's endangered species director, thinks the FWS avoids listings to avoid controversy—that it has internalized opposition to the ESA.

He and other experts also say that work regarding endangered species is drastically underfunded. As more species are listed, the funding per species declines. “Congress hasn't come to grips with the biodiversity crisis,” says Baier, who lobbies lawmakers regularly. “When you talk to them about biodiversity, their eyes glaze over.” Just this year federal lawmakers enacted a special provision exempting the Mountain Valley Pipeline from the ESA and other challenges, much as Congress had exempted the Tellico Dam. Environmentalists say the gas pipeline, running from West Virginia to Virginia, threatens the Candy Darter, a colorful small fish. The Inflation Reduction Act of 2022 provided a rare bit of good news: it granted the FWS $62.5 million to hire more biologists to prepare recovery plans.

The ESA is often likened to an emergency room for species: overcrowded and understaffed, it has somehow managed to keep patients alive, but it doesn't do much more. The law contains no mandate to restore ecosystems to health even though it recognizes such work as essential for thriving wildlife. “Its goal is to make things better, but its tools are designed to keep things from getting worse,” Bean says. Its ability to do even that will be severely tested in coming decades by threats it was never designed to confront.

T he ESA requires a species to be listed as “threatened” if it might be in danger of extinction in the “foreseeable future.” The foreseeable future will be warmer. Rising average temperatures are a problem, but higher heat extremes are a bigger threat, according to a 2020 study.

Scientists have named climate change as the main cause of only a few extinctions worldwide. But experts expect that number to surge. Climate change has been “a factor in almost every species we've listed in at least the past 15 years,” Frazer says. Yet scientists struggle to forecast whether individual species can “persist in place or shift in space”—as Stein and his co-authors put it in a recent paper—or will be unable to adapt at all and will go extinct. On June 30 the FWS issued a new rule that will make it easier to move species outside their historical range—a practice it once forbade except in extreme circumstances.

Credit: June Minju Kim ( graphic ); Brown Bird Design ( illustrations ); Sources: U.S. Fish & Wildlife Service Environmental Conservation Online System; U.S. Federal Endangered and Threatened Species by Calendar Year https://ecos.fws.gov/ecp/report/species-listings-by-year-totals ( annual data through 2022 ); Listed Species Summary (Boxscore) https://ecos.fws.gov/ecp/report/boxscore ( cumulative data up to September 18, 2023, and annual data for coral ); Delisted Species https://ecos.fws.gov/ecp/report/species-delisted ( delisted data through 2022 )

Eventually, though, “climate change is going to swamp the ESA,” says J. B. Ruhl, a law professor at Vanderbilt University, who has been writing about the problem for decades. “As more and more species are threatened, I don't know what the agency does with that.” To offer a practical answer, in a 2008 paper he urged the FWS to aggressively identify the species most at risk and not waste resources on ones that seem sure to expire.

Yet when I asked Frazer which urgent issues were commanding his attention right now, his first thought wasn't climate; it was renewable energy. “Renewable energy is going to leave a big footprint on the planet and on our country,” he says, some of it threatening plants and animals if not implemented well. “The Inflation Reduction Act is going to lead to an explosion of more wind and solar across the landscape.

Long before President Joe Biden signed that landmark law, conflicts were proliferating: Desert Tortoise versus solar farms in the Mojave Desert, Golden Eagles versus wind farms in Wyoming, Tiehm's Buckwheat (a little desert flower) versus lithium mining in Nevada. The mine case is a close parallel to that of Snail Darters versus the Tellico Dam. The flower, listed as endangered just last year, grows on only a few acres of mountainside in western Nevada, right where a mining company wants to extract lithium. The Center for Biological Diversity has led the fight to save it. Elsewhere in Nevada people have used the ESA to stop, for the moment, a proposed geothermal plant that might threaten the two-inch Dixie Valley Toad, discovered in 2017 and also declared endangered last year.

Does an absolute duty to preserve all endangered species make sense in such places? In a recent essay entitled “A Time for Triage,” Columbia law professor Michael Gerrard argues that “the environmental community has trade-off denial. We don't recognize that it's too late to preserve everything we consider precious.” In his view, given the urgency of building the infrastructure to fight climate change, we need to be willing to let a species go after we've done our best to save it. Environmental lawyers adept at challenging fossil-fuel projects, using the ESA and other statutes, should consider holding their fire against renewable installations. “Just because you have bullets doesn't mean you shoot them in every direction,” Gerrard says. “You pick your targets.” In the long run, he and others argue, climate change poses a bigger threat to wildlife than wind turbines and solar farms do.

For now habitat loss remains the overwhelming threat. What's truly needed to preserve the U.S.'s wondrous biodiversity, both Stein and Ruhl say, is a national network of conserved ecosystems. That won't be built with our present politics. But two more practical initiatives might help.

The first is the Recovering America's Wildlife Act, which narrowly missed passage in 2022 and has been reintroduced this year. It builds on the success of the 1937 Pittman-Robertson Act, which funds state wildlife agencies through a federal excise tax on guns and ammunition. That law was adopted to address a decline in game species that had hunters alarmed. The state refuges and other programs it funded are why deer, ducks and Wild Turkeys are no longer scarce.

The recovery act would provide $1.3 billion a year to states and nearly $100 million to Native American tribes to conserve nongame species. It has bipartisan support, in part, Stein says, because it would help arrest the decline of a species before the ESA's “regulatory hammer” falls. Although it would be a large boost to state wildlife budgets, the funding would be a rounding error in federal spending. But last year Congress couldn't agree on how to pay for the measure. Passage “would be a really big deal for nature,” Curry says.

Oyster Mussel. Epioblasma capsaeformis. Listed as Endangered: 1997. Status: Still endangered. Credit: © Joel Sartore/National Geographic Photo Ark

The second initiative that could promote species conservation is already underway: bringing landowners into the fold. Most wildlife habitat east of the Rocky Mountains is on private land. That's also where habitat loss is happening fastest. Some experts say conservation isn't likely to succeed unless the FWS works more collaboratively with landowners, adding carrots to the ESA's regulatory stick. Bean has long promoted the idea, including when he worked at the Interior Department from 2009 to early 2017. The approach started, he says, with the Red-cockaded Woodpecker.

When the ESA was passed, there were fewer than 10,000 Red-cockaded Woodpeckers left of the millions that had once lived in the Southeast. Humans had cut down the old pine trees, chiefly Longleaf Pine, that the birds excavate cavities in for roosting and nesting. An appropriate tree has to be large, at least 60 to 80 years old, and there aren't many like that left. The longleaf forest, which once carpeted up to 90 million acres from Virginia to Texas, has been reduced to less than three million acres of fragments.

In the 1980s the ESA wasn't helping because it provided little incentive to preserve forest on private land. In fact, Bean says, it did the opposite: landowners would sometimes clear-cut potential woodpecker habitat just to avoid the law's constraints. The woodpecker population continued to drop until the 1990s. That's when Bean and his Environmental Defense Fund colleagues persuaded the FWS to adopt “safe-harbor agreements” as a simple solution. An agreement promised landowners that if they let pines grow older or took other woodpecker-friendly measures, they wouldn't be punished; they remained free to decide later to cut the forest back to the baseline condition it had been in when the agreement was signed.

That modest carrot was inducement enough to quiet the chainsaws in some places. “The downward trends have been reversed,” Bean says. “In places like South Carolina, where they have literally hundreds of thousands of acres of privately owned forest enrolled, Red-cockaded Woodpecker numbers have shot up dramatically.”

The woodpecker is still endangered. It still needs help. Because there aren't enough old pines, land managers are inserting lined, artificial cavities into younger trees and sometimes moving birds into them to expand the population. They are also using prescribed fires or power tools to keep the longleaf understory open and grassy, the way fires set by lightning or Indigenous people once kept it and the way the woodpeckers like it. Most of this work is taking place, and most Red-cockaded Woodpeckers are still living, on state or federal land such as military bases. But a lot more longleaf must be restored to get the birds delisted, which means collaborating with private landowners, who own 80 percent of the habitat.

Leo Miranda-Castro, who retired last December as director of the FWS's southeast region, says the collaborative approach took hold at regional headquarters in Atlanta in 2010. The Center for Biological Diversity had dropped a “mega petition” demanding that the FWS consider 404 new species for listing. The volume would have been “overwhelming,” Miranda-Castro says. “That's when we decided, ‘Hey, we cannot do this in the traditional way.’ The fear of listing so many species was a catalyst” to look for cases where conservation work might make a listing unnecessary.

An agreement affecting the Gopher Tortoise shows what is possible. Like the woodpeckers, it is adapted to open-canopied longleaf forests, where it basks in the sun, feeds on herbaceous plants and digs deep burrows in the sandy soil. The tortoise is a keystone species: more than 300 other animals, including snakes, foxes and skunks, shelter in its burrows. But its numbers have been declining for decades.

Urbanization is the main threat to the tortoises, but timberland can be managed in a way that leaves room for them. Eager to keep the species off the list, timber companies, which own 20 million acres in its range, agreed to figure out how to do that—above all by returning fire to the landscape and keeping the canopy open. One timber company, Resource Management Service, said it would restore Longleaf Pine on about 3,700 acres in the Florida panhandle, perhaps expanding to 200,000 acres eventually. It even offered to bring other endangered species onto its land, which delighted Miranda-Castro: “I had never heard about that happening before.” Last fall the FWS announced that the tortoise didn't need to be listed in most of its range.

Miranda-Castro now directs Conservation Without Conflict, an organization that seeks to foster conversation and negotiation in settings where the ESA has more often generated litigation. “For the first 50 years the stick has been used the most,” Miranda-Castro says. “For the next 50 years we're going to be using the carrots way more.” On his own farm outside Fort Moore, Ga., he grows Longleaf Pine—and Gopher Tortoises are benefiting.

Whooping Crane. Grus americana. Listed as Endangered: 1967. Status: Still endangered. Credit: © Joel Sartore/National Geographic Photo Ark

The Center for Biological Diversity doubts that carrots alone will save the reptile. It points out that the FWS's own models show small subpopulations vanishing over the next few decades and the total population falling by nearly a third. In August 2023 it filed suit against the FWS, demanding the Gopher Tortoise be listed.

The FWS itself resorted to the stick this year when it listed the Lesser Prairie-Chicken, a bird whose grassland home in the Southern Plains has long been encroached on by agriculture and the energy industry. The Senate promptly voted to overturn that listing, but President Biden promised to veto that measure if it passes the House.

B ehind the debates over strategy lurks the vexing question: Can we save all species? The answer is no. Extinctions will keep happening. In 2021 the FWS proposed to delist 23 more species—not because they had recovered but because they hadn't been seen in decades and were presumed gone. There is a difference, though, between acknowledging the reality of extinction and deliberately deciding to let a species go. Some people are willing to do the latter; others are not. Bean thinks a person's view has a lot to do with how much they've been exposed to wildlife, especially as a child.

Zygmunt Plater, a professor emeritus at Boston College Law School, was the attorney in the 1978 Snail Darter case, fighting for hundreds of farmers whose land would be submerged by the Tellico Dam. At one point in the proceedings Justice Lewis F. Powell, Jr., asked him, “What purpose is served, if any, by these little darters? Are they used for food?” Plater thinks creatures such as the darter alert us to the threat our actions pose to them and to ourselves. They prompt us to consider alternatives.

The ESA aims to save species, but for that to happen, ecosystems have to be preserved. Protecting the Northern Spotted Owl has saved at least a small fraction of old-growth forest in the Pacific Northwest. Concern about the Red-cockaded Woodpecker and the Gopher Tortoise is aiding the preservation of longleaf forests in the Southeast. The Snail Darter wasn't enough to stop the Tellico Dam, which drowned historic Cherokee sites and 300 farms, mostly for real estate development. But after the controversy, the presence of a couple of endangered mussels did help dissuade the TVA from completing yet another dam, on the Duck River in central Tennessee. That river is now recognized as one of the most biodiverse in North America.

The ESA forced states to take stock of the wildlife they harbored, says Jim Williams, who as a young biologist with the FWS was responsible for listing both the Snail Darter and mussels in the Duck River. Williams grew up in Alabama, where I live. “We didn't know what the hell we had,” he says. “People started looking around and found all sorts of new species.” Many were mussels and little fish. In a 2002 survey, Stein found that Alabama ranked fifth among U.S. states in species diversity. It also ranks second-highest for extinctions; of the 23 extinct species the FWS recently proposed for delisting, eight were mussels, and seven of those were found in Alabama.

One morning this past spring, at a cabin on the banks of Shoal Creek in northern Alabama, I attended a kind of jamboree of local freshwater biologists. At the center of the action, in the shade of a second-floor deck, sat Sartore. He had come to board more species onto his photo ark, and the biologists—most of them from the TVA—were only too glad to help, fanning out to collect critters to be decanted into Sartore's narrow, flood-lit aquarium. He sat hunched before it, a black cloth draped over his head and camera, snapping away like a fashion photographer, occasionally directing whoever was available to prod whatever animal was in the tank into a more artful pose.

As I watched, he photographed a striated darter that didn't yet have a name, a Yellow Bass, an Orangefin Shiner and a giant crayfish discovered in 2011 in the very creek we were at. Sartore's goal is to help people who never meet such creatures feel the weight of extinction—and to have a worthy remembrance of the animals if they do vanish from Earth.

With TVA biologist Todd Amacker, I walked down to the creek and sat on the bank. Amacker is a mussel specialist, following in Williams's footsteps. As his colleagues waded in the shoals with nets, he gave me a quick primer on mussel reproduction. Their peculiar antics made me care even more about their survival.

There are hundreds of freshwater mussel species, Amacker explained, and almost every one tricks a particular species of fish into raising its larvae. The Wavy-rayed Lampmussel, for example, extrudes part of its flesh in the shape of a minnow to lure black bass—and then squirts larvae into the bass's open mouth so they can latch on to its gills and fatten on its blood. Another mussel dangles its larvae at the end of a yard-long fishing line of mucus. The Duck River Darter Snapper—a member of a genus that has already lost most of its species to extinction—lures and then clamps its shell shut on the head of a hapless fish, inoculating it with larvae. “You can't make this up,” Amacker said. Each relationship has evolved over the ages in a particular place.

The small band of biologists who are trying to cultivate the endangered mussels in labs must figure out which fish a particular mussel needs. It's the type of tedious trial-and-error work conservation biologists call “heroic,” the kind that helped to save California Condors and Whooping Cranes. Except these mussels are eyeless, brainless, little brown creatures that few people have ever heard of.

For most mussels, conditions are better now than half a century ago, Amacker said. But some are so rare it's hard to imagine they can be saved. I asked Amacker whether it was worth the effort or whether we just need to accept that we must let some species go. The catch in his voice almost made me regret the question.

“I'm not going to tell you it's not worth the effort,” he said. “It's more that there's no hope for them.” He paused, then collected himself. “Who are we to be the ones responsible for letting a species die?” he went on. “They've been around so long. That's not my answer as a biologist; that's my answer as a human. Who are we to make it happen?”

Robert Kunzig is a freelance writer in Birmingham, Ala., and a former senior editor at National Geographic, Discover and Scientific American .

Scientific American Magazine Vol 329 Issue 4

REPORTS, ARTICLES AND RESEARCH PAPERS

Endangered species.

• Paving the Road to Extinction: Congress’ Expanded Assault on Endangered Species Through Appropriations Poison-Pill Riders .Kurose, S., and Hartl, B., Center for Biological Diversity, January 2024. • Recovery of the Grizzly Bear at the Intersection of Law and Science . Greenwald, N. August 2023. • No Refuge: How America’s National Wildlife Refuges Are Needlessly Sprayed With Nearly Half a Million Pounds of Pesticides Each Year . Connor, H. May 2018. • Mexico's 10 Most Iconic Endangered Species . Olivera, A. April 2018. • A Wall in the Wild: The Disastrous Impacts of Trump's Border Wall on Wildlife . Greenwald, N., Segee, B., Curry, T. and Bradley, C. May 2017. • Pollinators in Peril: A Systematic Status Review of North American and Hawaiian Native Bees . Kopec, K., Center for biological Diversity, February 2017. • Removing the Walls to Recovery: Top 10 Species Priorities for a New Administration. Endangered Species Coalition (including the Center). December 2016. • Shortchanged: Funding Needed to Save America's Most Endangered Species . Greenwald, N., Hartl, , B., Mehrhoff, L., Pang, J. December 2016. • Taxa, Petitioning Agency, and Lawsuits Affect Time Spent Awaiting Listing Under the US Endangered Species Act . Greenwald, N., Kesler, D., Puckett, E. Biological Conservation . September 2016. • Fishing Down Nutrients on Coral Reefs . Allgeier, J.E., Valdivia,A., Cox, C. & Layman, C.A. Nature Communications . August 2016. • A Wild Success: A Systematic Review of Bird Recovery Under the Endangered Species Act . Suckling, K., Mehrhoff, L., 2016. Beam, R. & Hartl, B. June 2016. • Poisoned Waters: How Cyanide Fishing and the Aquarium Trade Are Devastating Coral Reefs and Tropical Fish . Center for Biological Diversity & For the Fishes. June 2016. • Lethal Loophole: How the Obama Administration Is Increasingly Allowing Special Interests to Endanger Rare Wildlife . Sanerib, T., Elkins, C., and Greenwald, N. February 2016. • Biodiversity on the Brink: The Role of “Assisted Migration" in Managing Endangered Species Threatened With Rising Seas . Lopez, J. Harvard Environmental Law Review Vol. 39. 2015. • Politics of Extinction: The Unprecedented Republican Attack on Endangered Species and the Endangered Species Act . Pand, J., and Greenwald, N. July 2015. • Runaway Risks: Oil Trains and the Government's Failure to Protect People, Wildlife and the Environments . Margolis, J., 2015. • Sea-Level Rise and Species Survival along the Florida Coast . Lopez, J. 2014. • Collision Course: The Government's Failing System for Protecting Florida Manatees from Deadly Boat Strikes . Center for Biological Diversity. September 2014. • Nourished by Wildfire: The Ecological Benefits of the Rim Fire and the Threat of Salvage Logging . Center for Biological Diversity and John Muir Projejct, January 2014. • Deadly Waters: How Rising Seas Threaten 233 Endangered Species . Center for Biological Diversity. 2013. • In Harm's Way: How the U.S. State Department and U.S. Fish and Wildlife Service Have Ignored the Dangers of the Keystone XL Pipeline to Endangered Species . Burd, L., Greenwald, N., & Bradley, C., 2013. • Dying for Protection: The 10 Most Vulnerable, Least Protected Amphibians and Reptiles in the United States . Adkins Giese, C. 2013. • On Thin Ice: After Five Years on the Endangered Species List, Polar Bears Still Face a Troubling Future . Center for Biological Diversity. 2013. • A Poor Track Record, but a Chance to Excel . Snape, W., 2013. The Environmental FORUM Environmental Law Institute, www.eli.org ) 30(1): 53. • Can A Multi-Species Habitat Conservation Plan Save San Diego's Vulnerable Vernal Pool Species? Buse, J., 2012. Golden Gate University Environmental Law Journal 6(1): 52-80. • On Time, On Target: How the Endangered Species Act Is Saving America's Wildlife . Suckling, K., Greenwald, N., Curry, T. 2012. • Protecting Rare Amphibians Under the U.S. Endangered Species Act . Adkins Giese, C., FrogLog (May 2012): 21-23. • White-nose Syndrome Headed to a Cave Near You . Matteson, M. Desert Report (June 2011): 6-7. • Impact of Dunes Sagebrush Lizard on Oil and Gas Activities in New Mexico . Lininger, J. & Bradley, C., 2011. • Assessing Protection for Imperiled Species of Nevada, U.S.A.: Are Species Slipping Through the Cracks of Existing Protections? Bradley, C. & Greenwald, N., 2008. • Not Too Late to Save the Polar Bear: A Rapid Action Plan to Address the Arctic Meltdown . Siegel, K., Cummings, B., Moritz, A. & Nowicki, B., 2007. • Status of the Bald Eagle in the Lower 48 States and the District of Columbia: 1963-2007 . Suckling, K. & Hodges, W., 2007. • The Bureaucratically Imperiled Mexican Wolf . Povilitis, A., Parsons, D.R., Robinson, M.J., & Becker, C.D., 2006. • A Review of Northern Goshawk Habitat Selection in the Home Range and Implications for Forest Management in the Western United States . Greenwald, D. N., Crocker-Bedford, C., Broberg, l., & Suckling, K., 2005. • Suitable Habitat for Jaguars in New Mexico . Robinson, M., Bradley, C., Boyd, J., 2005. • Impacts of the 2003 Southern California Wildfires on Four Species Listed as Threatened or Endangered Under the Federal Endangered Species Act: Quino Checkerspot Butterfly, Mountain Yellow-legged Frog, Coastal California Gnatcatcher, Least Bell's Vireo . Bond, M. & Bradley, C., 2003. • A Conservation Alternative for the Management of the Four Southern California National Forests (Los Padres, Angeles, San Bernardino, Cleveland) . Penrod, K., et al., 2002. • Analysis of Compliance by U.S. Forest Service Southwestern Region with Incidental Take Statements Issued by the U.S. Fish and Wildlife Service in Three Biological Opinions of 1999 . Taylor, M. 2001.

ENDANGERED SPECIES ACT

• Taxa, Petitioning Agency, and Lawsuits Affect Time Spent Awaiting Listing Under the US Endangered Species Act . Greenwald, N., Kesler, D., Puckett, E. Biological Conservation . September 2016. • A Wild Success: A Systematic Review of Bird Recovery Under the Endangered Species Act . Suckling, K., Mehrhoff, L., Beam, R. & Hartl, B. June 2016. • Saving Species and Wild Spaces: 10 Extraordinary Places Saved by the Endangered Species Act , Pang, J. & Hartl, B. May 2016. • Politics of Extinction: The Unprecedented Republican Attack on Endangered Species and the Endangered Species Act . Pang, J., and Greenwald, N. July 2015. • A Different Perspective on the Endangered Species Act at 40 Responding to Damien M. Schiff . Buse, J., 2015. University of California, Davis 38(1): 145-166. • Making Room for Wolf Recovery: The Case for Maintaining Endangered Species Act Protections for America's Wolves . Weiss, A., Greenwald, N. & Bradey, C. Center for Biological Diversity, November 2014. • A Wild Success: American Voices on the Endangered Species Act at 40 . Center for Biological Diversity, Endangered Species Coalition, Defenders of Wildlife, February 2014. • On Time, On Target: How the Endangered Species Act Is Saving America's Wildlife . Suckling, K., Greenwald, N., Curry, T., 2012. • A Future for All: A Blueprint for Strengthening the Endangered Species Act . 2011. • Effects on Species' Conservation of Reinterpreting the Phrase “Significant Portion of its Range” in the U.S. Endangered Species Act . Greenwald, N., 2009. Conservation Biology 23(6): 1375-1377. • State Endangered Species Acts . In Baur, D.C. & Irvin, W.R. (eds.), Endangered Species Act: Law, Policy, and Perspectives , second edition. American Bar Association. George, S. & Snape, W., 2010. • Politicizing Extinction: The Bush Administration's Dangerous Approach to Endangered Wildlife . Greenwald, N., 2007. • Measuring the Success of the Endangered Species Act, Recovery Trends in the Northeastern United States . Suckling, K.F., 2006. • Factors Affecting the Rate and Taxonomy of Species Listings under the US Endangered Species Act . In Gobel, D, Scott, M.J. & Davis, F.W. (eds.), The Endangered Species Act at Thirty: Renewing the Conservation Commitment . Island Press. Greenwald, D.N., Suckling, K.F. & Taylor, M.F.J., 2006. • Critical Habitat and Recovery . In: Gobel, D., Scott, M.J. & Davis, F.W. (eds.), The Endangered Species Act at Thirty: Renewing the Conservation Commitmen t. Island Press. Suckling, K.F. & Taylor, M.F.J., 2006. • The Listing Record . In Gobel, D., Scott, M.J., & Davis, F.W. (eds.), The Endangered Species Act at Thirty: Renewing the Conservation Commitmen t. Island Press. Greenwald, D.N., K.F. Suckling and M.F.J. Taylor, 2006. • Progress or Extinction? A Systematic Review of the U.S. Fish and Wildlife Service's Endangered Species Act Listing Program. 1974-2004 . Greenwald, D. N. & Suckling, K. F., 2005 • The Effectiveness of the Endangered Species Act: A Quantitative Analysis . Taylor, M.F.J., Suckling, K.F. & Rachlinski, J.J., 2005. BioScience 55(4): 360-367. • Extinction and the Endangered Species Act . Suckling, K., Nowicki, B. & Slack, R., 2004. • A Review of the Bush Critical Habitat Record . 2003. • Bush Administration Attacks Endangered Species Act . • Safeguarding Citizen Rights Under the Endangered Species Act . Senatore, M., & Suckling, K., 2001.

BIODIVERSITY

• Hidden In Plain Sight: California's Native Habitats Are Valuable Carbon Sinks . Yap, T., Prabhala, A., Anderson, I. Center for Biological Diversity. July 2023. • Bullfrogs: A Trojan Horse for a Deadly Fungus? Yap, T., Koo, M., Ambrose, R., Vredenburg, V.T. Science Journal for Kids . October 2018. • Mexico's 10 Most Iconic Endangered Species . Olivera, A. April 2018. • A Multi-method Approach to Delineate and Validate Migratory Corridors . Bond, M., Bradley, C., Kiffner, C., Morrison, T., and Lee, D. Landscape Ecology . May 2017. • Biodiversity on the Brink: The Role of “Assisted Migration" in Managing Endangered Species Threatened With Rising Seas . Lopez, J. Harvard Environmental Law Review Vol. 39. 2015. • Nourished by Wildfire: The Ecological Benefits of the Rim Fire and the Threat of Salvage Logging . Center for Biological Diversity and John Muir Projejct, January 2014. • Joining the Convention on Biological Diversity: A Legal and Scientific Overview of Why the United States Must Wake Up . Snape, B., 2010. Sustainable Development Law & Policy 10(3): 6-18. • Highways to Hell: A Critical Examination of the Environmental Impacts of the Security and Prosperity Partnership . Lopez, J., 2009. [3 MB version] • Rana Aurora (Northern Red-legged Frog) Egg Mass Disturbance. Curry, T. R., and Hayes, M. P., 2009. Herpetological Review 40(2): 208-209. • Greenwashing Risks to Baby-boomers Abroad: An Assessment of Available Strategies to Address “Green” Marketing Misrepresentation to U.S. Retiree Real Estate Investors Overseas. 2009. • Life History Diversity and Protection of the Southwestern Washington/Columbia River Distinct Population Segment of the Coastal Cutthroat Trout . Greenwald, N. & Mashuda, S., 2008. • Predation on the Coastal Tailed Frog ( Ascaphus truei ) by a Shrew ( Sorex spp.) in Washington State . Lund, E., Hayes, M., Curry, T., Marsten, J. & Young, 2008. Northwestern Naturalist 89(3): 200-202. • Assessing Protection for Imperiled Species of Nevada, U.S.A.: Are Species Slipping Through the Cracks of Existing Protections? Greenwald, N. & Bradley, C., 2008. • Medicinal Plants at Risk — Nature's Pharmacy, Our Treasure Chest: Why We Must Preserve Our Natural Heritage . Roberson, E., 2008. • Species of Concern of the Tillamook Rainforest and North Coast, Oregon . Greenwald, N. & Garty, A., 2007. • The Bering Sea: A Biodiversity Assessment of Vertebrate Species . Greenwald, N., Callimanis, S., Garty, A. & Peters, E., 2006. • Saving All the Parts: Protecting Species of Northwest Old-growth Forests . Greenwald, N. & Greason, S., 2004. • Imperiled Western Trout and the Importance of Roadless Areas . 2001. • A Conservation Alternative for the Management of the Four Southern California National Forests (Los Padres, Angeles, San Bernardino, Cleveland) . Penrod, K., et al., 2002. • Principles of Wildlife Corridor Design . Bond, M., 2003.

• A Wall of Lights Through the Wild: 1,800 Stadium Lights on Arizona Conservation Lands Threaten Wildlife . McSpadden, R., Jordahl, L., and Bradley, C. Center for Biological Diversity. June 2023. • Hidden In Plain Sight: California's Native Habitats Are Valuable Carbon Sinks . Yap, T., Prabhala, A., Anderson, I. Center for Biological Diversity. July 2023. • Deadpool Highway: How Interstate 11 Would Worsen Arizona’s Water Crisis . McSpadden, R., and Bradley, C. Center for Biological Diversity. May 2023. • State of Utom River 2022: Challenges, Opportunities for Southern California’s Signature River . Center for Biological Diversity. August 2022. • A Wall in the Wild: The Disastrous Impacts of Trump's Border Wall on Wildlife . Greenwald, N., Segee, B., Curry, T. and Bradley, C. May 2017. • A Multi-Method Approach to Delineate and Validate Migratory Corridors . Bond, M., Bradley, C., Kiffner, C., Morrison, T., and Lee, D. Landscape Ecology . May 2017. • Public Lands Enemies: 15 Federal Lawmakers Plotting to Seize, Destroy and Privatize America's Public Lands . Spivak, R. & Beam, R. March 2017. • Runaway Risks: Oil Trains and the Government's Failure to Protect People, Wildlife and the Environments . Margolis, J., 2015. • Nourished by Wildfire: The Ecological Benefits of the Rim Fire and the Threat of Salvage Logging . Center for Biological Diversity and John Muir Projejct, January 2014. • Groups Join Together to Confront Water-rights Issue . Mrowka, R. Desert Report (June 2011): 2, 13. • Saving Our National Legacy: The Future of America's Last Heritage Forests . Fink, M., Kassar, C., Matteson, M., and McKinnon, T., July 2009. • America's Newest Fossil Beds National Monument: Tule Springs/Upper Las Vegas Wash . Mrowka, R. and Davis, L., 2009. • Wild at Heart: Saving the Last of America's Backcountry . 2008. • Imperiled Western Trout and the Importance of Roadless Areas . 2001. • Protection and Conservation of Roadless Areas in the Southwest . Greenwald, N. • A Conservation Alternative for the Management of the Four Southern California National Forests (Los Padres, Angeles, San Bernardino, Cleveland) . Penrod, K., et al., 2002.

CLIMATE CHANGE

• Flight Path: A Trajectory for U.S. Aviation to Meet Global Climate Goals . Center for Biological Diversity. October 2020. • From Bailout to Righting the Course: The Commonsense Action the United States Must Take to Address the Flood Crisis . Lopez, J. 2020. • Stealing California's Future: How Monterey County's Dirty Oil Business Worsens the Climate Crisis . Center for Biological Diversity. September 2016. • Throwing Shade: 10 Sunny States Blocking Distributed Solar Development . Greer, R. April 2016. • Up in the Air: How Airplane Carbon Pollution Jeopardizes Global Climate Goals . Pardee, V. December 2015. • Biodiversity on the Brink: The Role of “Assisted Migration" in Managing Endangered Species Threatened With Rising Seas . Lopez, J. Harvard Environmental Law Review Vol. 39. 2015. • Grounded: The President's Power to Fight Climate Change, Protect Public Lands by Keeping Publicly Owned Fossil Fuels in the Ground . Saul, M., McKinnon, T., Spivak, R., 2015. • What Happens When Species Move But Reserves Do Not? Creating Climate Adaptive Solutions to Climate Change . Whipps, N., 2015. Hastings Law Journal Vol. 66. • Runaway Risks: Oil Trains and the Government's Failure to Protect People, Wildlife and the Environments . Margolis, J., 2015. • The Potential Greenhouse Gas Emissions From U.S. Federal Fossil Fuels . Ecoshift Consulting, Center for Biological Diversity, Friends of the Earth. August 2015. • Troubled Waters: Offshore Fracking's Threat to California's Ocean, Air and Seismic Stability . Center for Biological Diversity, 2014. • On Shaky Ground: Fracking, Acidizing, and Increased Earthquake Risk in California . Earthworks, Center for Biological Diversity, Clean Water Action, 2014. • Deadly Waters: How Rising Seas Threaten 233 Endangered Species . Center for Biological Diversity, 2013. • The New Normal: Climate Change Victims in Post- Kiobel United States Federal Courts . Lopez, J., 2013. Charleston Law Review 8(1). • Not Just a Number: Achieving a CO 2 Concentration of 350 ppm or Less to Avoid Catastrophic Climate Impacts. Center for Biological Diversity and 350.org, 2010. • Extinction: It's Not Just for Polar Bears. A Center for Biological Diversity and Care for the Wild International report. Wolf, S., 2010. • Yes, He Can: President Obama's Power to Make an International Climate Commitment Without Waiting for Congress . Bundy, K., Cummings, B., Pardee, V. & Siegel, K., 2009. • 350 Reasons We Need to Get to 350: Species Threatened by Global Warming; An Interactive Installation by the Center for Biological Diversity . 2009. • No Reason to Wait: Reducing Greenhouse Gas Emissions Through the Clean Air Act . Siegel, K., Snape, W., and Vespa, M., June 2009. • Why 350? Climate Policy Must Aim to Stabilize Greenhouse Gases at the Level Necessary to Minimize the Risk of Catastrophic Outcomes . Vespa, M., 2009. Ecology Law Currents 36(1): 185-194. • Fuel to Burn: The Climate and Public Health Implications of Off-road Vehicle Pollution in California . Kassar, C. & Spitler, P., 2008. • Not Too Late to Save the Polar Bear: A Rapid Action Plan to Address the Arctic Meltdown . Siegel, K., Cummings, B., Moritz, A. & Nowicki, B., 2007. • The California Environmental Quality Act: On the Front Lines of California's Fight Against Global Warming . Siegel, K., Vespa, M. & Nowicki, B., 2007.

• Powerless in the United States: How Utilities Drive Shutoffs and Energy Injustice . Center for Biological Diversity, March 2023. • Rooftop-Solar Justice: Why Net Metering is Good for People and the Planet and Why Monopoly Utilities Want to Kill It . Crystal,. H., Lin, R., and Su, J., Center for Biological Diversity, Energy and Policy Institute, BailoutWatch, January 2023. • Fueling Extinction: How Dirty Energy Drives Wildlife to the Brink . Endangered Species Coalition (incl. the Center for Biological Diversity), 2012. • A Deadly Toll: The Gulf Oil Spill and the Unfolding Wildlife Disaster . 2011. Center for Biological Diversity. • What We Should Learn From the BP Spill . Lopez, J., 2011. Environmental Law News 20 (1): 35. • Too Much Oil for the Rubber Stamp: The Government's Role in the BP Oil Spill . Lopez, J., 2011. • BP's Well Evaded Environmental Review: Categorical Exclusion Policy Remains Unchanged . Lopez, J., 2010. Ecology Law Currents 37 (93): 93-103. • Corporate Profile of Salt River Project . Draffan, G., 2001. • Ecological and Community Problems with Biomass-to-Energy . Schulke, T.

ENVIRONMENTAL HEALTH/POLLUTION

• Collateral Damage: How Factory Farming Drives Upthe Use of Toxic Agricultural Pesticides . Center for Biological Diversity, World Animal Protection, 2022. • Pesticides and Environmental Injustice in the USA: Root Causes, Current Regulatory Reinforcement and a Path Forward . Donley, N., Bullard, R., Economos, J., Figueroa, I., Lee, J., Liebman, A., Navarro Martinez, D., & Shafiei, F. BMC Public Health , April 2022. • Toxic Hangover: How the EPA Is Approving New Products With Dangerous Pesticides It Committed to Phasing Out . Donley, N., Jan. 2020. • A Menace to Monarchs: Drift-prone Dicamba Poses a Dangerous New Threat to Monarch Butterflies . Donley, N., March 2018. • Toxic Concoctions: How the EPA Ignores the Dangers of Pesticide Cocktails . Donley, N., July 2016. • Can't We Just All Get Along: Reconciling Pesticide Use and Species Protection . Lopez, J. 2015. • Lost in the Mist: How Glyphosate Use Disproportionately Threatens California's Most Impoverished Counties . Center for Biological Diversity, 2015. • Perdido en la niebla: Como El uso de glifosato desproporcionadamente amenaza los condados más pobres de California . Center for Biological Diversity, 2015. • Dispersants: The Lesser of Two Evils or a Cure Worse Than the Disease? Kilduff, C. and Lopez, J., 2012. Ocean and Coastal Law Journal 16 (2): 375-394. • Endocrine-disrupting Chemical Pollution: Why the EPA Should Regulate These Chemicals Under the Clean Water Act . Lopez, J., 2010. Sustainable Development Law & Policy 10(3): 19-23. • Poisoning Our Imperiled Wildlife: San Francisco Bay Area Endangered Species at Risk from Pesticides . Miller, J., Miller, J., Beeland, T.D. & Bradley, C., 2006. • Silent Spring Revisited: Pesticide Use and Endangered Species . Litmans, B. & Miller, J, 2004.

POPULATION AND SUSTAINABILITY

• Alternative Economies: Uplifting Activities for a Sustainable Future . Dennings, K., Adoma, A.; 2023. • At What Cost: Unraveling the Harms of the Fast Fashion Industry . Shedlock, K., Feldstein, S.; 2023. • Too Hot for Knitwear: Climate Crisis, Biodiversity and Fashion Brands Using Woll and Synthetics . Feldstein, S., Hakansson, E.; 2023. • Talking Trash: U.S. Perspectives on the Language of Waste Reduction . Dennings, K., Adoma, A.; 2023. • Unwrapped: Perceptions of Winter Holiday Consumerism, Gift Giving and Waste . Dennings, K., Adoma, A; 2023. • The Influence of Environmental Toxicity, Inequity and Capitalism on Reproductive Health . Dennings, K., Grossman, A; 2022. • Gender and the Climate Crisis: Equitable Solutions for Climate Plans . Dennings, K., Baillie, S., and Baxter, C; 2022. • Public Perceptions on Population: US Survey Results . Dennings, K., Baillie, S., Ricciardi, R. and Addo, A; 2022; Population and Sustainability 6(1): 1-23. • Sheer Destruction: Wool, Fashion and the Biodiversity Crisis . Feldstein, S., Hakansson, E., Katcher, J., Vance, V.; 2021. • Endangered Species Condoms: A Social Marketing Tool for Starting Conversations About Population . Baillie, S., Dennings, K. and Feldstein S.; 2020; Journal of Population and Sustainability 4(2): 31-44. • Contraception and Consumption in the Age of Extinction: U.S. Survey Results . Dennings, K., 2020. • Appetite for Change: A Policy Guide to Reducing Greenhouse Gas Emissions of U.S. Diets by 2030 . Feldstein, S., 2020. • Catering to the Climate: How Earth-Friendly Menus at Events Can Help Save the Planet . Molidor, J., Emery., I., 2019. • Towards a Psychology of the Food‐Energy‐Water Nexus: Costs and Opportunities . Dreyer, S.J., Kurz, T., Prosser, A.M.B., Abrash, A.W., Dennings, K., McNeill, I., Saber, D.A., Swim, J.K., 2019. Journal of Social Issues 76(1). • Slow Road to Zero: A Report Card on U.S. Supermarkets’ Path to Zero Food Waste . Molidor, J., Feldstein, S., Figueiredo, J., 2019. • Checked Out: How U.S. Supermarkets Fail to Make the Grade in Reducing Food Waste . Molidor, J., Feldstein, S., 2018. • Wasting Biodiversity: Why Food Waste Needs to Be a Conservation Priority . Feldstein, S., 2017. Biodiversity 18 (2-3): 75-77. • Habitat-Fed Food: Grass-fed Beef and Sustainable Solutions . Molidor, J., 2017. Biodiversity 18 (2-3): 78-81.

FIRE AND FOREST RESTORATION

• Nourished by Wildfire: The Ecological Benefits of the Rim Fire and the Threat of Salvage Logging . Center for Biological Diversity and John Muir Projejct, January 2014. • Influence of Pre-Fire Tree Mortality on Fire Severity in Conifer Forests of the San Bernardino Mountains, California , 2009. Bond, M., Lee, D. E., Bradley, C. & Hanson, T. Open Forest Science Journal 2:41-47. • Impacts of the 2003 Southern California Wildfires on Four Species Listed as Threatened or Endangered Under the Federal Endangered Species Act: Quino Checkerspot Butterfly, Mountain Yellow-legged Frog, Coastal California Gnatcatcher, Least Bell's Vireo . Bond, M. & Bradley, C., 2003. • Ecological Restoration of Southwestern Ponderosa Pine Ecosystems: A Broad Perspective . Allen, C.D., Savage, M., Falk, D.A., Suckling, K. F., Swetnam, T. W., Schulke, T., Stacey, P. B., Morgan, P., Hoffman, M. & Klingel, J. T., 2002. Ecological Applications 12(5): 1418-1433. • Prelude to Catastrophe: Recent and Historic Land Management within the Rodeo-Chedeski Fire Area . • Effectively Treating the Wildland-Urban Interface to Protect Houses and Communities from the Threat of Forest Fire . Nowicki, B., 2002. • Protection and Conservation of Roadless Areas in the Southwest . Greenwald, N. • An Ecologically Integrated Approach to Managing Dwarf Mistletoe (Arceuthobium) in Southwest Forests . Pollock, Michael M., Ph. D. Kieran Suckling, 1995. • A Conservation Alternative for the Management of the Four Southern California National Forests (Los Padres, Angeles, San Bernardino, Cleveland) . Penrod, K., et al., 2002. • Fire & Forest Ecosystem Health in the American Southwest . Suckling, K., 1996.

LIVESTOCK GRAZING

• Costs and Consequences: The Real Price of Livestock Grazing on America's Public Lands . Glaser, C., Romaniello, C. & Moskowitz, K. (prepared for the Center for Biological Diversity), 2015. • Assessing the Full Cost of the Federal Grazing Program . Moskowitz, K., & Romaniello, C., 2002. • Ecological Restoration of Southwestern Ponderosa Pine Ecosystems: A Broad Perspective . Allen, C.D., Savage, M., Falk, D.A., Suckling, K.F., Swetnam, T.W., Schulke, T., Stacey, P.B., Morgan, P., Hoffman, M. & Klingel, J.T., 2002. Ecological Applications 12(5): 1418-1433. • Cattle Grazing and the Loss of Biodiversity in the East Bay . • Livestock Grazing, Fire Regimes, and Tree Densities: A Literature Review .

• Frogs . In Bernheimer, K. (ed.), Brothers and Beasts: An Anthology of Men on Fairy Tales. Wayne State University Press. Suckling, K.F., 2007. • Biodiversity, Linguistic Diversity and Identity — Toward an Ecology of Language in an Age of Extinction . Suckling, K., 2000. Langscape 17: 14-20. • A House on Fire: Connecting the Biological and Linguistic Diversity Crises . 2002. Animal Law 6: 193-202.

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The Center for Biological Diversity is a 501(c)(3) registered charitable organization. Tax ID: 27-3943866.

3D DNA Preserved for 52,000 Years in Freeze-Dried Woolly Mammoth Remains

For the first time, researchers have mapped ancient genetic material in unprecedented detail

Daily Correspondent

Gloved hand holding up a bit of hair from a dark brown blob

Some 52,000 years ago, a female woolly mammoth with a shaggy, mullet-like mane died in a cave in Siberia. The region’s dry, cold climate freeze-dried the hulking creature’s body, transforming its flesh and skin into what amounted to woolly mammoth jerky.

Now, the well-preserved creature—nicknamed Chris Waddle, after the retired English soccer player known for his business-in-the-front, party-in-the-back-style haircut—is giving up some of the extinct species’ secrets. Using a piece of skin from near the animal’s ear, scientists have reconstructed the three-dimensional architecture of its DNA, according to a new paper published this week in the journal Cell .

This unprecedented feat, which involved more than 50 international scientists, offers new insights into how the animal’s genes behaved while it was still alive. More broadly, their methods may help support the conservation of today’s living animals and, possibly, aid in efforts to “ de-extinct” the woolly mammoth .

“To get as close to a real mammoth as possible, one needs to know how the [genetic] architecture differs from an Asian elephant,” says Hendrik Poinar , a biologist at McMaster University in Hamilton, Ontario, who was not involved with the research, to NewScientist ’s Corryn Wetzel.

Usually, after an animal dies, its DNA molecules begin to break down and spread out, leaving behind a jumbled mess of genetic material. When researchers later try to study that DNA, it’s like trying to read the scattered pages of a book that’s been turned upside down and shaken. They can still learn a lot, but this heap of genetic information gives them an incomplete picture.

However, because of the way the 52,000-year-old woolly mammoth was preserved, the geometry of its genetic material remained surprisingly intact, allowing researchers to reconstruct its genetic code in remarkable detail. To do so, they used a novel technique known as “PaleoHi-C,” which helped them map sections of DNA and reassemble the genome in its original, three-dimensional configuration. In this case, studying the mammoth’s ancient DNA was like reading “an ordered stack [of pages] with dog-eared corners,” writes Scientific American ’s Saima S. Iqbal.

By seeing the structure of the genome, scientists can “figure out which genes were active in that particular animal at the moment that it died and which genes were repressed,” says study co-author Marc A. Marti-Renom, a researcher at the National Center for Genomic Analysis in Barcelona, to the Washington Post ’s Lizette Ortega.

Researchers compared the mammoth’s DNA to the genome of modern Asian elephants . They found plenty of similarities—for instance, that both animals had 28 pairs of chromosomes—but also some important distinctions. Roughly 4.1 percent of the two species’ skin genes were different, including one relating to hair growth, reports the New York Times ’ Siobhan Roberts.

Their analysis showed that the gene responsible for hair growth was more active in the mammoth than in today’s elephants, which helps explain why modern pachyderms are bald while their ancient ancestors had luscious locks. They also pinpointed the genes responsible for the mammoth’s cold tolerance.

Gloved hands holding a small brown object in one hand and a scalpel in the other

The team was curious to know whether the mammoth’s impeccably preserved DNA was a fluke—and whether their “PaleoHi-C” method would work on other specimens. So, they conducted a series of laboratory experiments with beef liver. They dehydrated some samples using both heat and freeze-drying, but kept others fresh and left them out at room temperature.

After three days, the fresh beef’s DNA had disintegrated into a mishmash of fragments. But the DNA in the dehydrated samples still had its three-dimensional structure a year later.

They even tried destroying the dehydrated DNA—using some pretty creative methods, like running over it with a car and firing a shotgun at it. But, still, it persisted.

Their hearty samples suggest the same method might be applied to other ancient creatures, even the remains of mummified humans, given the right preservation conditions.

“This new work opens up major new possibilities of exploring the biology of extinct species,” says Adrian Lister, a paleontologist at the Natural History Museum in London who was not involved with the research, to the Guardian ’s Ian Sample. “This exceptional preservation might be found in fossils much older … back to 2 million years ago, opening the possibility to investigate the biology of much older extinct species and their relationship to and differences from living relatives.”

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Sarah Kuta is a writer and editor based in Longmont, Colorado. She covers history, science, travel, food and beverage, sustainability, economics and other topics.

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July 18, 2024

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Project to sequence genomes of 40,000 plant, animal and fungi species in Catalan-speaking territories

by University of Barcelona

Earth BioGenome Project to sequence the genome of nearly 40,000 plant, animal and fungi species in Catalan-speaking territories

Biodiversity loss is one of the most alarming threads the planet faces. Degraded habitats, overexploited resources, climate crisis and invasive species are some of the factors that threaten the richness and variety of living species.

The rapid and progressive disappearance of organisms—some experts talk about a sixth mass extinction—will create major imbalances and ecosystems, alter ecological cycles and relationships between species, affecting all forms of life, including the human species.

Sequencing the genomes of all plants, animals and fungi on Earth—about 2 million known species—to protect biodiversity as we know it: This is the aim of the Earth BioGenome Project (EBP), which will characterize the genomic biodiversity of species in different regions of the planet.

The Catalan Initiative for the Earth BioGenome Project (CBP) is also participating in this international project, which will sequence the genomes of the eukaryotic species—that is, those with cells that have a defined nucleus—that are in the Catalan-speaking territories (Andorra, Northern Catalonia, Balearic Islands, the Valencian Community and Principality of Catalonia).

Now, an article in the journal NAR Genomics and Bioinformatics has reported on the CBP project.

The main authors of the text are Professor Montserrat Corominas, from the UB's Faculty of Biology, the UB Institute of Biomedicine (IBUB) and the Institute for Catalan Studies (IEC), and Professor Roderic Guigó, from the Cenetr for Genomic Regulation (CRG), Pompeu Fabra University (UPF) and IEC. The NARGAB article explicitly cites the Catalan translation, which is available in the Zenodo database.

Sequencing genomes to protect species

Knowing the genome of living beings is decisive for designing tools and strategies to help minimize—or even reverse—the loss of biodiversity and the extinction of species. A quarter of all known species on the European continent are found in the Països Catalans (Catalan-speaking territories), where there is a high level of biodiversity and an abundance of endemic species, many of which are seriously threatened by global climate change , which is likely to have a major ecological impact on the Mediterranean basin, especially in freshwater ecosystems and mountain areas.

"One of the great achievements of the Catalan Initiative for the Earth BioGenome Project (CBP) is that it has been able to encourage scientists from very different disciplines within biology, areas in which they have traditionally worked in isolation from each other.

"This favors interdisciplinary research , which is essential for the progress of science," says Montserrat Corominas, professor at the UB's Department of Genetics, Microbiology and Statistics and head of the REGnetREG research group at the UB.

Obtaining the genomes of all species on Earth "may be the most important project in the history of science, and one of the most important in the history of mankind. Knowing these genomes will provide knowledge of biological processes with unprecedented resolution.

"All this knowledge will have an impact that we cannot yet even imagine in areas such as medicine, agriculture, biotechnology, etc., and also in many industrial processes, which are increasingly dependent on biological processes.

"This scientific milestone will therefore be essential for the development of the bioeconomy, i.e. an economy that develops with nature and not against nature," stresses expert Roderic Guigó, head of the Computational Biology and Health Genomics research program at the Center for Genomic Regulation (CRG).

The Balearic shearwater: A genome of reference in conservation

Biologists, botanists, zoologists, geneticists, bioinformaticists, microbiologists, ecologists and other experts have contributed their research efforts to an investigation that, for now, has the sequencing of the genomes of 76 species in its sights.

In the pilot phase of the PBC, which began in the summer of 2020, a digitized catalogue of the eukaryotic species living in Catalonia has been created, with species of little-explored taxa, such as the freshwater flagellate (Singekia montserratensis); rare, endemic or difficult to locate species, such as the Catalan blind scorpion (Belisarius xambeui), or those considered emerging as biological models, such as the wall lizard (Podarcis muralis).

The genomes of endangered species such as the Montseny brook newt (Calotriton arnoldi), the most endangered amphibian in Europe, or the red coral (Corallium rubrum); species used in medicine, such as the Pyrenean chamomile (Achillea ptarmica subsp. pyrenaica), or of economic interest, such as the pearly razorfish (Xyrichtys novacula), are also to be provided.

One of the first genomes sequenced is that of the Balearic shearwater (Puffinus mauretanicus), a marine bird endemic to the Balearic Islands, critically endangered—especially due to accidental captures in longliners—according to the International Union for Conservation of Nature (IUCN).

Professors Marta Riutort and Julio Rozas, from the UB's Faculty of Biology and the UB Biodiversity Research Institute (IRBio) have coordinated the study to decipher this genome of reference in conservation.

"Having the complete genome has allowed us to evaluate the real situation of the Balearic shearwater populations much better," says Riutort. "It has also opened the way for us to develop a tool that should help in their conservation and which has already aroused the interest of the groups involved," adds Rozas.

Addressing the challenge of biodiversity genomics

Nearly 150 experts from institutions such as the UB, CRG, IBE-UPF-CSIC, ICREA, CNAG, ICTA-UAB, BSC-CNS, CRAG, ICBIBE, CSIC-UIB and IBB, among others, have participated in this project. Most of the genomes are sequenced at the National Center for Genomic Analysis (CNAG), based at the Barcelona Science Park (PCB), and the results are available on the PBC website .

"Thanks to the advances in DNA sequencing technologies and analysis procedures, we can obtain high-quality reference genomes of animal and plant species at a rate unthinkable just a few years ago," says expert Tyler Alioto, head of CNAG's genome assembly and annotation group.

"Analyzing sequencing data to form a genome is equivalent to deciphering a jigsaw puzzle with millions of pieces. It has been necessary to develop powerful computational tools."

Sharing resources to protect biodiversity worldwide

The article published now highlights the rich biodiversity of the territories that have historically shared a strong cultural tradition, mainly reflected in the use of the Catalan language. Thus, the PBC was promoted in 2019 by the Catalan Society of Biology (SCB), thanks to the legacy of Leandre Cervera (1891–1964)—president of the entity in hiding during Franco's regime—with the initial support of the Catalan Institution of Natural History (ICHN) and the Institute for Catalan Studies (IEC).

For the authors, this paper is also a way of bringing their research closer to all citizens, who, in the end, are the ones who fund the research activity. This is particularly relevant as part of an initiative open to the whole of society that appeals to a shared cultural and linguistic heritage.

Since June 2024, the coordination group that manages the activities of the project—which is renewed every four years—is led by Marta Riutort (UB-IRBio) and Javier del Campo (Institute of Evolutionary Biology-IBE).

Beyond the borders of the Catalan-speaking territories, the PBC wants to form part of a global transformative movement to raise social awareness of the threat that biodiversity loss generates for human well-being, promoting a different and more balanced relationship with nature around the world.

"Our wish is that, when the international project comes to an end, we will be able to say that we have made a significant contribution from our countries," conclude Montserrat Corominas and Roderic Guigó.

Provided by University of Barcelona

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Environment

In a first, sea rise kills off a Florida Keys species

Alex Harris Miami Herald (TNS)

MIAMI — Key Largo has a new, disturbing and first-of-its-kind graveyard. There are no headstones, no burial markers, no names, no bodies.

It’s the last place an incredibly rare species of tree called the Key Largo tree was seen alive, back in 2023. The killer? All the clues point to climate change.

At least, that’s what a newly published paper suggests. Scientists have been watching this particular stand of cacti — known for their height (up to 20 feet) and brown hairlike puffball they grow around their flowers — since the 1990s.

At the time, researchers determined that a two-acre patch in John Pennekamp State Park was the only population in the U.S. of Pilosocereus millspaughii, an offshoot from the larger Caribbean population of the cactus.

But as of last year, the very last of the bunch is gone. And researchers believe sea level rise was the main culprit — rising tides and groundwater turning the soil too salty for the plant to survive. It appears this local extinction (also known as extirpation) could be the first climate-driven demise of a species in the United States.

“As far as we know, from any published research we can find, this is the first case we can find,” same James Lange, lead botanist with Fairchild Tropical Botanical Gardens and co-author of the study, which was published Tuesday in the Journal of the Botanical Research Institute of Texas.

“It was tragic to see as we monitored this over the years,” he said. “It was a big, old beautiful plant, one of the things that makes the Keys unique. And we’ve lost it.”

While the unique tree cactus may be the first recorded species to go locally extinct due to sea level rise in the U.S., plenty of other species are threatened too. And some on the same key.

Last year, a new study found that the endangered silver rice rat, which calls the Florida Keys home, shifted its population along with the rising tide. Researchers strapped telemetry collars to the tiny critters and tracked their movements. Over 17 years, they discovered the rats of three separate islands in the Keys shifted to higher elevations as seas rose in the area. If seas continue to rise, the rice rats could be left with nowhere to live.

Another study, from University of Miami researcher Taylor Alexander in 1976, explicitly pointed to sea level rise as the reason why slash pines could no longer exist on Key Largo. The soil was just too salty, he found.

George Gann, executive director at the Institute for Regional Conservation and co-author of the study, said these stories are examples of the threats sea rise can bring to bear, but they’re also an opportunity for scientists to collaborate and figure out how to save imperiled species before it’s too late.

“This is kind of the stake in the ground where we will see many other species lost to the impacts of climate change and sea level rise. And that is indeed sad,” he said. “This is the game. We have to figure out how do we stop the incredible loss of species and move to a position of ecological restoration.”

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A disappearing act

Scientists started watching the tiny strand of cacti, located in an outcrop within John Pennekamp State Park, closely around 2007, by which time the trees had already survived multiple hurricanes, including the quadruple-whammy of 2005.

By 2015, the population was on the decline. Only 60 plants were recorded in that year’s annual survey, half as many as researchers spotted in 2013.

By 2016, only 28 plants remained, and animals like raccoons and birds were chomping on the few survivors. It was the only year scientists noticed so many bite marks, and they wondered if it could be because high tides could have drowned most of the freshwater puddles those animals rely on for clean drinking water, so they turned to juicy, water-filled cacti instead.

“Perhaps due to these tidal influences, freshwater resources may have been limited at the time,” Lange said. “We see this potential correlation.”

Hurricane Irma, which walloped the island chain in 2017, struck another decisive blow with 1.5 feet of storm surge over the area. And by 2019, the colony was all but dead. And for the first time, scientists noted, salty king tides were now within a few inches of the base of the cacti. During that time, a neighborhood on the same key had standing water on its roads for three straight months. The spot where the cacti lived was at an even lower elevation.

“We weren’t able to visit the population during this time, because the island was flooded,” Lange said.

A rescue effort

The sight of the yellowing, withering and felled cacti moved scientists to action. They rescued what they could: cuttings sliced off their decaying parents and seeds from the pulpy, magenta fruit.

Today, they’re proud of the three dozen fragments, 25 seedlings and more than 1,000 seeds they have saved. The survivors are split between Fairchild Gardens and John Pennekamp State Park.

But it wasn’t enough to resuscitate a dying species, at least, not on this solo patch of land.

Last July, researchers went back to the site. They found a single cactus, a little over a foot tall, surrounded by limestone exposed by encroaching, salty seas and a new surrounding crop of mangroves and other salt-tolerant plants.

They cut down the sole survivor and took it back to the nursery, where they thought it would have a better chance of survival.

These species aren’t just threatened by sea level rise, which is gradually increasing along the entire Florida coast, but by “pulse events,” Gann said.

“It’s the king tides. It’s the storm surge from hurricanes that does not drain off as fast as it used to. Because of the speed of sea level rise, you don’t have the nice gradual shift in habitats you have on barrier islands,” he said. “That’s not what we’re seeing, we’re seeing overwash, we’re seeing complete transformation.”

That makes it tricky, but not impossible, for scientists to try and replant the salvaged snippets of the tree cactus.

The plan is to find some open land in Key Largo in the next few years and replant the fragments botanists are currently cultivating. It could buy the species “five, ten, thirty years,” Gann said.

“It can be quite difficult to find the perfect place where a plant that wasn’t there before can survive,” said Alan Franck, collections manager for the Florida Museum of Natural History and co-author of the study.

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IMAGES

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Animal Extinction Research Project
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COMMENTS

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The loss of biodiversity is one of the most critical current environmental problems, threatening valuable ecosystem services and human well-being (1-7).A growing body of evidence indicates that current species extinction rates are higher than the pre-human background rate (8-15), with hundreds of anthropogenic vertebrate extinctions documented in prehistoric and historic times (16-23).
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Communicating biodiversity loss and extinction. In the Summary for Policy Makers Footnote 60 and at the launch of the IPBES GA, the finding that 1 million species are currently threatened with extinction took a central position. It featured prominently in the press release by IPBES and, as we noted before, it attracted considerable attention in news and social media as well.
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The loss of biological diversity is one of the most severe human-caused global environmental problems. Hundreds of species and myriad populations are being driven to extinction every year (1-8).From the perspective of geological time, Earth's richest biota ever is already well into a sixth mass extinction episode (9-14).Mass extinction episodes detected in the fossil record have been ...
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For example, taxonomists described 1230 species of birds after 1900, and 13 of them are now extinct or possibly extinct. This cohort accumulated 98,334 species-years—meaning that an average species has been known for 80 years. The extinction rate is (13/98,334) × 10 6 = 132 E/MSY.
Circling the drain: the extinction crisis and the future of humanity
The extinction dynamics depicted here represent the prelude of the global extinction of species and are exemplified by numerous species of plants and animals. For example, from a sample of 177 species of mammals, just shy of 50% exhibited a range contraction of at least 80% in the period of 1990-2015 [ 44 ].
Climate-Related Local Extinctions Are Already Widespread among ...
Author Summary Climate change is an important threat to the world's plant and animal species, including species on which humans depend. However, predicting how species will respond to future climate change is very difficult. In this study, I analyze the extinctions caused by the climate change that has already occurred. Numerous studies find that species are shifting their geographic ranges ...
Accelerating extinction risk from climate change
Overall, 7.9% of species are predicted to become extinct from climate change; (95% CIs, 6.2 and 9.8) ().Results were robust to model type, weighting scheme, statistical method, potential publication bias, and missing studies (fig. S1 and table S2) ().This proportion supports an estimate from a 5-year synthesis of studies ().Its divergence from individual studies (1-4) can be explained by ...
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Up to one million plant and animal species face extinction, many within decades, because of human activities, says the most comprehensive report yet on the state of global ecosystems. Without ...
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However, recent research on reptiles shows a promising avenue to advance this debate. In a new PLOS Biology paper, de Oliveira Caetano and colleagues [ 6] presented an innovative machine learning analysis to estimate the extinction risk of 4,369 reptile species that were unassessed or data deficient in the Red List.
Frontiers
Introduction. A key objective of conservation science is to understand the patterns and drivers of species declines and extinction to reduce the loss of biodiversity (Soulé, 2013).In the Anthropocene, human activities are driving the sixth mass extinction and pose the greatest threats to wildlife (Dirzo et al., 2014; Ceballos et al., 2015).A robust understanding of extinction is therefore ...
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Research article An animal crisis caused by pollution, deforestation
This research shows that anthropogenic environmental perturbations will drive 4 ± 2% of marine animal species and 9 ± 4% of terrestrial tetrapod species to extinction during 2060-2080 CE. Furthermore, a major nuclear war concurrent with environmental perturbations will lead to at most a ∼40% loss in marine animal species and ∼60% loss ...
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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 ...
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The bucardo - an endemic ibex from the Pyrenees - is the only extinct animal to have ever been cloned, and for seven short minutes in 2003, "extinction was not forever." Using the bucardo's extinction as a starting point, rather than an ending, this paper addresses the "spectral ecologies" of the Pyrenees.
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We used 73 datasets collected worldwide containing 4489 species from four major taxa [2682 arthropods, 1260 birds, 282 herptiles (reptiles and amphibians), and 265 mammals] (Fig. 1, fig. S1, and tables S1 and S2) to provide a global test of the extinction filter hypothesis in forest ecosystems ().In the presence of an extinction filter, species inhabiting a filtered landscape with high levels ...
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