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1.
PLoS One ; 19(5): e0299783, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38748670

RESUMO

Unsustainable trade in big cats affects all species in the genus, Panthera, and is one of the foremost threats to their conservation. To provide further insight into the impact of policy interventions intended to address this issue, we examine the case study of the Republic of Korea (South Korea), which in the early 1990s was one of the world's largest importers of tiger (Panthera tigris) bone and a major manufacturer of tiger-derived medicinal products. In 1993, South Korea became a Party to the Convention on International Trade in Endangered Species (CITES) and introduced a ban on commercial trade in CITES Appendix I-listed big cats a year later. We used an expert-based questionnaire survey and an exploration of the CITES trade database to investigate what has since happened to big cat trade in South Korea. Expert opinion suggested that big cat trade has likely substantially reduced since the early 1990s, as a result of the trade ban and broad socioeconomic changes. However, illegal trade has not been eradicated entirely and we were able to confirm that products reportedly derived from big cats were still publicly available for sale on a range of Korean online marketplaces, sometimes openly. The items most commonly reported by respondents from post-1994 trade and supported by expert-led evidence were tiger and leopard (Panthera pardus) skins and tiger bone wine. Although South Korea may provide a useful case study of a historically significant consumer country for tiger which has made strong progress in addressing unsustainable levels of big cat trade within a short period of time, there remains a need to address recalcitrant small-scale, illegal trade. We also recommend further investigation regarding reports of South Korean nationals being involved in illegal trade in tiger-derived products in Southeast Asia.


Assuntos
Comércio , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , República da Coreia , Animais , Comércio/tendências , Conservação dos Recursos Naturais/legislação & jurisprudência , Conservação dos Recursos Naturais/tendências , Espécies em Perigo de Extinção/legislação & jurisprudência , Espécies em Perigo de Extinção/tendências , Espécies em Perigo de Extinção/estatística & dados numéricos , Tigres , Panthera , Inquéritos e Questionários , Gatos
2.
PLoS One ; 19(5): e0300371, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38753613

RESUMO

Chameleons (family Chamaeleonidae) are a distinctive group of reptiles, mainly found in Africa, which have high local endemism and face significant threats from the international wildlife trade. We review the scale and structure of international chameleon trade, with a focus on collection in and exports from Tanzania; a hotspot of chameleon diversity. Analysis used data from the CITES Trade Database 2000-2019, combined with assessment of online trade, and on-the-ground surveys in Tanzania in 2019. Between 2000 and 2019, 1,128,776 live chameleons from 108 species were reported as exported globally, with 193,093 of these (from 32 species) exported by Tanzania. Both global and Tanzanian chameleon exports declined across the study period, driven by decreased trade in generalist genera. Whilst the proportion of captive-bred individuals increased across time for the generalist taxa, the majority of range-restricted taxa in trade remained largely wild-sourced. For Tanzanian exports, 41% of chameleons were from one of the 23 endemic species, and 10 of the 12 Tanzanian endemic species in trade are categorised as threatened with extinction by IUCN. In terms of online trade, of the 42 Tanzanian species assessed, there was evidence of online sale for 83.3% species, and 69% were actively for sale with prices listed. Prices were on average highest for Trioceros species, followed by Kinyongia, Rieppeleon, Rhampholeon, and Chameleo. Field work in Tanzania provided evidence that the historic harvest of endemic chameleon species has been higher than the quantities of these species reported as exported by Tanzania in their annual trade reports to CITES. However, we found no field evidence for trade in 2020 and 2021, in line with Tanzanian regulations that applied a blanket ban on all exports of live wild animals. Literature evidence, however, suggests that illegal trade continued to Europe from seizures of Tanzanian chameleon species in Austria in 2021.


Assuntos
Animais Selvagens , Comércio , Conservação dos Recursos Naturais , Lagartos , Animais , Tanzânia , Espécies em Perigo de Extinção/estatística & dados numéricos , Espécies em Perigo de Extinção/tendências , Biodiversidade , Comércio de Vida Silvestre
3.
BMC Ecol Evol ; 24(1): 64, 2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38764016

RESUMO

Flying foxes of the genus Pteropus, especially those inhabiting islands, face increasing pressure from anthropogenic threats. A first step to implementing effective conservation actions is to establish monitoring projects to understand a species' population status and trend. Pteropus species are highly affected by seasonality which further requires regular, repeated, and long-term data to understand population trends, and reactions to severe weather events. In the present case study, a regular, bi-annual population census was implemented on Comoros between 2016 and 2023 for the highly threatened Livingstone's fruit bat, Pteropus livingstonii, and compared the results of standardized monitoring to historical population data. Seasonality had a large impact on the number of bats found at roost sites, with more bats present in the wet season, but the data over the past eight years revealed no significant in- or decrease in the number of bats counted on the island Anjouan. We estimated around 1,200-1,500 bats on Anjouan and 300-400 bats on Mohéli, and found that landcover type has no measurable effect on population distribution at roost sites. Our study highlights the need for long-term surveys to understand past population trends and that single counts are not sufficient to draw final conclusions of a species' status.


Assuntos
Quirópteros , Espécies em Perigo de Extinção , Estações do Ano , Animais , Comores/epidemiologia , Espécies em Perigo de Extinção/tendências , Espécies em Perigo de Extinção/estatística & dados numéricos , Dinâmica Populacional/tendências , Conservação dos Recursos Naturais/tendências , Densidade Demográfica
5.
Nature ; 623(7985): 100-105, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37880359

RESUMO

Illegal harvesting and trading of wildlife have become major threats to global biodiversity and public health1-3. Although China is widely recognized as an important destination for wildlife illegally obtained abroad4, little attention has been given to illegal hunting within its borders. Here we extracted 9,256 convictions for illegal hunting from a nationwide database of trial verdicts in China spanning January 2014 to March 2020. These convictions involved illegal hunting of 21% (n = 673) of China's amphibian, reptile, bird and mammal species, including 25% of imperilled species in these groups. Sample-based extrapolation indicates that many more species were taken illegally during this period. Larger body mass and range size (for all groups), and proximity to urban markets (for amphibians and birds) increase the probability of a species appearing in the convictions database. Convictions pertained overwhelmingly to illegal hunting for commercial purposes and involved all major habitats across China. A small number of convictions represented most of the animals taken, indicating the existence of large commercial poaching operations. Prefectures closer to urban markets show higher densities of convictions and more individual animals taken. Our results suggest that illegal hunting is a major, overlooked threat to biodiversity throughout China.


Assuntos
Animais Selvagens , Biodiversidade , Caça , Animais , Anfíbios , Aves , China , Bases de Dados Factuais , Espécies em Perigo de Extinção/economia , Espécies em Perigo de Extinção/legislação & jurisprudência , Espécies em Perigo de Extinção/estatística & dados numéricos , Caça/economia , Caça/legislação & jurisprudência , Caça/estatística & dados numéricos , Mamíferos , Répteis
6.
Nature ; 622(7982): 308-314, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37794184

RESUMO

Systematic assessments of species extinction risk at regular intervals are necessary for informing conservation action1,2. Ongoing developments in taxonomy, threatening processes and research further underscore the need for reassessment3,4. Here we report the findings of the second Global Amphibian Assessment, evaluating 8,011 species for the International Union for Conservation of Nature Red List of Threatened Species. We find that amphibians are the most threatened vertebrate class (40.7% of species are globally threatened). The updated Red List Index shows that the status of amphibians is deteriorating globally, particularly for salamanders and in the Neotropics. Disease and habitat loss drove 91% of status deteriorations between 1980 and 2004. Ongoing and projected climate change effects are now of increasing concern, driving 39% of status deteriorations since 2004, followed by habitat loss (37%). Although signs of species recoveries incentivize immediate conservation action, scaled-up investment is urgently needed to reverse the current trends.


Assuntos
Anfíbios , Mudança Climática , Ecossistema , Espécies em Perigo de Extinção , Animais , Anfíbios/classificação , Biodiversidade , Mudança Climática/estatística & dados numéricos , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/tendências , Espécies em Perigo de Extinção/estatística & dados numéricos , Espécies em Perigo de Extinção/tendências , Extinção Biológica , Risco , Urodelos/classificação
7.
Nature ; 622(7981): 101-106, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37758956

RESUMO

Protected areas (PAs) are the primary strategy for slowing terrestrial biodiversity loss. Although expansion of PA coverage is prioritized under the Convention on Biological Diversity, it remains unknown whether PAs mitigate declines across the tetrapod tree of life and to what extent land cover and climate change modify PA effectiveness1,2. Here we analysed rates of change in abundance of 2,239 terrestrial vertebrate populations across the globe. On average, vertebrate populations declined five times more slowly within PAs (-0.4% per year) than at similar sites lacking protection (-1.8% per year). The mitigating effects of PAs varied both within and across vertebrate classes, with amphibians and birds experiencing the greatest benefits. The benefits of PAs were lower for amphibians in areas with converted land cover and lower for reptiles in areas with rapid climate warming. By contrast, the mitigating impacts of PAs were consistently augmented by effective national governance. This study provides evidence for the effectiveness of PAs as a strategy for slowing tetrapod declines. However, optimizing the growing PA network requires targeted protection of sensitive clades and mitigation of threats beyond PA boundaries. Provided the conditions of targeted protection, adequate governance and well-managed landscapes are met, PAs can serve a critical role in safeguarding tetrapod biodiversity.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Filogenia , Vertebrados , Animais , Aves/classificação , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/estatística & dados numéricos , Vertebrados/classificação , Espécies em Perigo de Extinção/estatística & dados numéricos , Espécies em Perigo de Extinção/tendências , Anfíbios/classificação , Répteis/classificação , Aquecimento Global/estatística & dados numéricos
8.
Primates ; 64(4): 407-413, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37140752

RESUMO

Monitoring the population size of threatened primate species with minimal disturbance is becoming an outstanding requirement for conservation and wildlife management. Drones with thermal infrared (TIR) and visible spectrum (RGB) imaging are increasingly used to survey arboreal primates, but ground-truthing is still required to assess the effectiveness of drone-based count estimates. Our pilot study aims to assess the ability of a drone with both TIR and RGB sensors to detect, count, and identify semi-wild population of four endangered species of langurs and gibbon in the Endangered Primate Rescue Center (EPRC) in northern Vietnam. We found that TIR imagery enabled higher detection rates compared to RGB imagery and obtained an accurate count with the TIR only after four drone flights. We could identify langurs species based on thermal signature at a flight height of 50 m from the ground level (max tree height = 15 m), via size and shape of the body. With TIR imagery, we were able to record inconspicuous behaviors such as foraging and play. While some individuals initially showed flight or avoidance behaviors when the drone was sighted, these behaviors decreased or were absent on following drone surveys. Our study suggests that monitoring and precisely counting langur and gibbon species populations could be successful with the use of thermal drones only.


Assuntos
Espécies em Perigo de Extinção , Presbytini , Dispositivos Aéreos não Tripulados , Animais , Espécies em Perigo de Extinção/estatística & dados numéricos , Hylobates , Projetos Piloto , Primatas , Dispositivos Aéreos não Tripulados/instrumentação , Vietnã , População , Raios Infravermelhos
10.
PLoS Genet ; 18(2): e1009974, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35143486

RESUMO

Wide-ranging animals, including migratory species, are significantly threatened by the effects of habitat fragmentation and habitat loss. In the case of terrestrial mammals, this results in nearly a quarter of species being at risk of extinction. Caribou are one such example of a wide-ranging, migratory, terrestrial, and endangered mammal. In populations of caribou, the proportion of individuals considered as "migrants" can vary dramatically. There is therefore a possibility that, under the condition that migratory behavior is genetically determined, those individuals or populations that are migratory will be further impacted by humans, and this impact could result in the permanent loss of the migratory trait in some populations. However, genetic determination of migration has not previously been studied in an endangered terrestrial mammal. We examined migratory behavior of 139 GPS-collared endangered caribou in western North America and carried out genomic scans for the same individuals. Here we determine a genetic subdivision of caribou into a Northern and a Southern genetic cluster. We also detect >50 SNPs associated with migratory behavior, which are in genes with hypothesized roles in determining migration in other organisms. Furthermore, we determine that propensity to migrate depends upon the proportion of ancestry in individual caribou, and thus on the evolutionary history of its migratory and sedentary subspecies. If, as we report, migratory behavior is influenced by genes, caribou could be further impacted by the loss of the migratory trait in some isolated populations already at low numbers. Our results indicating an ancestral genetic component also suggest that the migratory trait and their associated genetic mutations could not be easily re-established when lost in a population.


Assuntos
Migração Animal/fisiologia , Genoma/genética , Rena/genética , Animais , Comportamento Animal/fisiologia , Evolução Biológica , Conservação dos Recursos Naturais/métodos , Ecologia/métodos , Ecossistema , Espécies em Perigo de Extinção/estatística & dados numéricos , Feminino , Genômica/métodos , Haplótipos , América do Norte , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Análise de Sequência de DNA/métodos
11.
Sci Rep ; 11(1): 18987, 2021 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-34556696

RESUMO

Detection of environmental DNA (eDNA) has become a commonly used surveillance method for threatened or invasive vertebrates in both aquatic and terrestrial environments. However, most studies in this field favor vertebrate target species. Environmental DNA protocols can be especially useful for endangered invertebrates such as the Hine's emerald dragonfly (Somatochlora hineana) where conservation efforts have been greatly hindered by training, time, overall costs, and environmental impacts associated with conducting surveys in the calcareous fens occupied by this species. An essential step in developing such a protocol is to evaluate the dynamics of eDNA concentration under controlled conditions. We used the quantitative polymerase chain reaction (qPCR) to examine seasonal shifts in the persistence and net-accumulation of eDNA from captive S. hineana larvae in experimental mesocosms at temperatures corresponding with their overwintering (5.0 °C) and active (16.0 °C) seasons. Environmental DNA persisted longer at 5.0 °C but accumulated more readily at 16.0 °C. Differences in the accumulation and persistence of eDNA reflect differences in the longevity of eDNA at different temperatures and seasonal differences in larval S. hineana behavior. This study highlights the importance of considering how seasonal changes in temperature influence not only the speed of eDNA degradation but also the target species' eDNA shedding rates.


Assuntos
DNA Ambiental/isolamento & purificação , Monitorização de Parâmetros Ecológicos/métodos , Espécies em Perigo de Extinção/estatística & dados numéricos , Odonatos/genética , Animais , DNA Ambiental/química , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Estudos de Viabilidade , Reação em Cadeia da Polimerase em Tempo Real , Estações do Ano , Temperatura
12.
PLoS One ; 16(9): e0256146, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34499686

RESUMO

Sharks and rays are at risk of extinction globally. This reflects low resilience to increasing fishing pressure, exacerbated by habitat loss, climate change, increasing value in a trade and inadequate information leading to limited conservation actions. Artisanal fisheries in the Bay of Bengal of Bangladesh contribute to the high levels of global fishing pressure on elasmobranchs. However, it is one of the most data-poor regions of the world, and the diversity, occurrence and conservation needs of elasmobranchs in this region have not been adequately assessed. This study evaluated elasmobranch diversity, species composition, catch and trade within the artisanal fisheries to address this critical knowledge gap. Findings show that elasmobranch diversity in Bangladesh has previously been underestimated. In this study, over 160000 individual elasmobranchs were recorded through landing site monitoring, comprising 88 species (30 sharks and 58 rays) within 20 families and 35 genera. Of these, 54 are globally threatened according to the IUCN Red List of Threatened Species, with ten species listed as Critically Endangered and 22 species listed as Endangered. Almost 98% juvenile catch (69-99% for different species) for large species sand a decline in numbers of large individuals were documented, indicating unsustainable fisheries. Several previously common species were rarely landed, indicating potential population declines. The catch pattern showed seasonality and, in some cases, gear specificity. Overall, Bangladesh was found to be a significant contributor to shark and ray catches and trade in the Bay of Bengal region. Effective monitoring was not observed at the landing sites or processing centres, despite 29 species of elasmobranchs being protected by law, many of which were frequently landed. On this basis, a series of recommendations were provided for improving the conservation status of the elasmobranchs in this region. These include the need for improved taxonomic research, enhanced monitoring of elasmobranch stocks, and the highest protection level for threatened taxa. Alongside political will, enhancing national capacity to manage and rebuild elasmobranch stocks, coordinated regional management measures are essential.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Espécies em Perigo de Extinção/estatística & dados numéricos , Pesqueiros/estatística & dados numéricos , Tubarões/fisiologia , Rajidae/fisiologia , Animais , Bangladesh , Mudança Climática , Oceanos e Mares , Dinâmica Populacional , Tubarões/classificação , Rajidae/classificação
13.
Sci Rep ; 11(1): 19397, 2021 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-34588514

RESUMO

The effective conservation of mammals on the brink of extinction requires an integrated socio-ecological approach, yet the updated ecological knowledge of species remains fundamental. This study brings spatiotemporal behaviour, population structure, age-specific survival rates, and population size estimate of the Western Derby eland (WDE) in the Niokolo Koba National Park (NKNP), Senegal, investigated during dry seasons 2017 and 2018. WDE was strongly localised in the core area of NKNP (< 5%), active throughout the day with the highest peak in the hottest daytime, with a mean group size 7.6 ± SE 8.9. The adult sex ratio was female-biased and showed low annual adult male survival rates. The population consisted of high proportion of juveniles, whilst adults did not exceed 40%. The estimated population density was 0.138 WDE/km2 (± 0.0102) and estimated size 195 WDE in NKNP (CI95 from 54 to 708 individuals). Findings highlighted that the WDE population has potential to expand in the NKNP, due to an underutilized capacity. The age-specific vital rates indicate adult males as the most vulnerable; suggesting either an increase in the large predators' population, livestock encroachment pressure, and/or poaching. Findings imply that targeted monitoring with science-based interpretation may bring forward strong conservation solutions to the protected area management decision-makers.


Assuntos
Antílopes , Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção/estatística & dados numéricos , Parques Recreativos/estatística & dados numéricos , Animais , Densidade Demográfica , Senegal
14.
PLoS One ; 16(8): e0255784, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34352882

RESUMO

As human pressures on the environment continue to spread and intensify, effective conservation interventions are direly needed to prevent threats, reduce conflicts, and recover populations and landscapes in a liaison between science and conservation. It is practically important to discriminate between true and false (or misperceived) effectiveness of interventions as false perceptions may shape a wrong conservation agenda and lead to inappropriate decisions and management actions. This study used the false positive risk (FPR) to estimate the rates of misperceived effectiveness of electric fences (overstated if reported as effective but actually ineffective based on FPR; understated otherwise), explain their causes and propose recommendations on how to improve the representation of true effectiveness. Electric fences are widely applied to reduce damage to fenced assets, such as livestock and beehives, or increase survival of fenced populations. The analysis of 109 cases from 50 publications has shown that the effectiveness of electric fences was overstated in at least one-third of cases, from 31.8% at FPR = 0.2 (20% risk) to 51.1% at FPR = 0.05 (5% risk, true effectiveness). In contrast, understatement reduced from 23.8% to 9.5% at these thresholds of FPR. This means that truly effective applications of electric fences were only 48.9% of all cases reported as effective, but truly ineffective cases were 90.5%, implying that the effectiveness of electric fences was heavily overstated. The main reasons of this bias were the lack of statistical testing or improper reporting of test results (63.3% of cases) and interpretation of marginally significant results (p < 0.05, p < 0.1 and p around 0.05) as indicators of effectiveness (10.1%). In conclusion, FPR is an important tool for estimating true effectiveness of conservation interventions and its application is highly recommended to disentangle true and false effectiveness for planning appropriate conservation actions. Researchers are encouraged to calculate FPR, publish its constituent statistics (especially treatment and control sample sizes) and explicitly provide test results with p values. It is suggested to call the effectiveness "true" if FPR < 0.05, "suggestive" if 0.05 ≤ FPR < 0.2 and "false" if FPR ≥ 0.2.


Assuntos
Espécies em Perigo de Extinção/estatística & dados numéricos , Comportamento Predatório , Animais , Biota , Interpretação Estatística de Dados , Estimulação Elétrica , Lobos/fisiologia
15.
Nat Commun ; 12(1): 5162, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34453040

RESUMO

Although species with larger body size and slow pace of life have a higher risk of extinction at a global scale, it is unclear whether this global trend will be consistent across biogeographic realms. Here we measure the functional diversity of terrestrial and freshwater vertebrates in the six terrestrial biogeographic realms and predict their future changes through scenarios mimicking a gradient of extinction risk of threatened species. We show vastly different effects of extinctions on functional diversity between taxonomic groups and realms, ranging from almost no decline to deep functional losses. The Indo-Malay and Palearctic realms are particularly inclined to experience a drastic loss of functional diversity reaching 29 and 31%, respectively. Birds, mammals, and reptiles regionally display a consistent functional diversity loss, while the projected losses of amphibians and freshwater fishes differ across realms. More efficient global conservation policies should consider marked regional losses of functional diversity across the world.


Assuntos
Biodiversidade , Espécies em Perigo de Extinção/estatística & dados numéricos , Vertebrados/classificação , Animais , Conservação dos Recursos Naturais , Ecossistema , Extinção Biológica , Vertebrados/crescimento & desenvolvimento
17.
Genes (Basel) ; 12(7)2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34210039

RESUMO

Mislabelling of fish and fish products has attracted much attention over the last decades, following public awareness of the practice of substituting high-value with low-value fish in markets, restaurants, and processed seafood. In some cases, mislabelling includes illegal, unreported, and unregulated (IUU) fishing, contributing to overexploit substitute species that are undetectable when sold under wrong names. This is the first study of DNA barcoding to assess the level of mislabelling in fish marketed in Ghana, focusing on endangered shark species. Genetic identification was obtained from 650 base pair sequences within the cytochrome c oxidase I (COI) gene. All except one of 17 shark fillets analysed were wrongly labelled as compared with none of 28 samples of small commercial pelagic fish and 14 commercial shark samples purchased in Europe. Several substitute shark species in Ghana are endangered (Carcharhinussignatus and Isurusoxyrinchus) and critically endangered (Squatina aculeata). Shark products commercialized in Europe (n = 14) did not reveal mislabelling, thus specific shark mislabelling cannot be generalized. Although based on a limited number of samples and fish markets, the results that reveal trade of endangered sharks in Ghana markets encourage Ghanaian authorities to improve controls to enforce conservation measures.


Assuntos
Espécies em Perigo de Extinção/estatística & dados numéricos , Produtos Pesqueiros/normas , Rotulagem de Alimentos/normas , Tubarões/genética , Animais , Código de Barras de DNA Taxonômico/normas , Espécies em Perigo de Extinção/legislação & jurisprudência , Pesqueiros/normas , Gana , Tubarões/fisiologia
18.
PLoS One ; 16(7): e0253895, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34197512

RESUMO

Assessing species status and making classification decisions under the Endangered Species Act is a critical step towards effective species conservation. However, classification decisions are liable to two errors: i) failing to classify a species as threatened or endangered that should be classified (underprotection), or ii) classifying a species as threatened or endangered when it is not warranted (overprotection). Recent surveys indicate threatened spectacled eider populations are increasing in western Alaska, prompting the U.S. Fish and Wildlife Service to reconsider the federal listing status. There are multiple criteria set for assessing spectacled eider status, and here we focus on the abundance and decision analysis criteria. We estimated population metrics using state-space models for Alaskan breeding populations of spectacled eiders. We projected abundance over 50 years using posterior estimates of abundance and process variation to estimate the probability of quasi-extinction. The decision analysis maps the risk of quasi-extinction to the loss associated with making a misclassification error (i.e., underprotection) through a loss function. Our results indicate that the Yukon Kuskokwim Delta breeding population in western Alaska has met the recovery criteria but the Arctic Coastal Plain population in northern Alaska has not. The methods employed here provide an example of accounting for uncertainty and incorporating value judgements in such a way that the decision-makers may understand the risk of committing a misclassification error. Incorporating the abundance threshold and decision analysis in the reclassification criteria greatly increases the transparency and defensibility of the classification decision, a critical aspect for making effective decisions about species management and conservation.


Assuntos
Tomada de Decisões Gerenciais , Técnicas de Apoio para a Decisão , Patos , Espécies em Perigo de Extinção/legislação & jurisprudência , Alaska , Animais , Teorema de Bayes , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Espécies em Perigo de Extinção/estatística & dados numéricos , Estados Unidos , Yukon
19.
PLoS One ; 16(7): e0253604, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34197517

RESUMO

Climate change and anthropogenic modifications to the landscape can have both positive and negative effects on an animal. Linking landscape change to physiological stress and fitness of an animal is a fundamental tenet to be examined in applied ecology. Cortisol is a glucocorticoid hormone that can be used to indicate an animal's physiological stress response. In the Sierra Nevada Mountains of California, fishers (Pekania pennanti) are a threatened mesocarnivore that have been subjected to rapid landscape changes due to anthropogenic modifications and tree mortality related to a 4-year drought. We measured cortisol concentrations in the hair of 64 fishers (41 females, 23 males) captured and radio-collared in the Sierra National Forest, California. We addressed two main questions: (1) Is the physiological stress response of fishers influenced by anthropogenic factors, habitat type, canopy cover, and tree mortality due to drought in their home range? (2) Does the physiological stress response influence survival, reproduction, or body condition? We examined these factors within a fisher home range at 3 scales (30, 60, 95% isopleths). Using model selection, we found that tree mortality was the principle driver influencing stress levels among individual fishers with female and male fishers having increasing cortisol levels in home ranges with increasing tree mortality. Most importantly, we also found a link between physiological stress and demography where female fishers with low cortisol levels had the highest annual survival rate (0.94), whereas females with medium and high cortisol had lower annual survival rates, 0.78 and 0.81, respectively. We found no significant relationships between cortisol levels and body condition, male survival, or litter size. We concluded that tree mortality related to a 4-year drought has created a "landscape of stress" for this small, isolated fisher population.


Assuntos
Mudança Climática , Secas , Espécies em Perigo de Extinção/estatística & dados numéricos , Mustelidae/fisiologia , Estresse Fisiológico , Animais , California , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Feminino , Florestas , Cabelo/química , Hidrocortisona/análise , Masculino , Taxa de Sobrevida , Árvores
20.
Nat Commun ; 12(1): 3694, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140481

RESUMO

Various prioritisation strategies have been developed to cope with accelerating biodiversity loss and limited conservation resources. These strategies could become more engaging for decision-makers if they reflected the positive effects conservation can have on future projected biodiversity, by targeting net positive outcomes in future projected biodiversity, rather than reflecting the negative consequences of further biodiversity losses only. Hoping to inform the post-2020 biodiversity framework, we here apply this approach of targeting net positive outcomes in future projected biodiversity to phylogenetic diversity (PD) to re-identify species and areas of interest for conserving global mammalian PD. We identify priority species/areas as those whose protection would maximise gains in future projected PD. We also identify loss-significant species/areas as those whose/where extinction(s) would maximise losses in future projected PD. We show that our priority species/areas differ from loss-significant species/areas. While our priority species are mostly similar to those identified by the EDGE of Existence Programme, our priority areas generally differ from previously-identified ones for global mammal conservation. We further highlight that these newly-identified species/areas of interest currently lack protection and offer some guidance for their future management.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Ecologia/métodos , Espécies em Perigo de Extinção , África Austral , Animais , Ásia Central , Sudeste Asiático , Evolução Biológica , Espécies em Perigo de Extinção/estatística & dados numéricos , Extinção Biológica , Madagáscar , Mamíferos , Filogenia
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