Extinction Risk Research Articles

지방소멸의 심화가 사회적경제 의존성에 미치는 영향 분석 - 감마 회귀 모형을 활용한 시군구 수준의 분석

The purpose of this study is to empirically analyze whether the degree of regional extinction intensifies dependency on the social economy. To achieve the purpose of the study, local municipalities in South Korea are utilized as the units of analysis. The dependent variables are proxy indicators measuring dependency on the social economy, while the main independent variable is the regional extinction index. Furthermore, to measure dependency on the social economy, this study utilizes the location quotient, which compares the proportion of the number of corporations, sales, and jobs created by the social economy within the municipality to national levels. Empirical results using gamma regression models indicate that in models where the number of corporations LQ and total sales LQ are set as dependent variables, an increase in extinction risk is associated with increased dependency on the social economy. However, no significant effects is observed in the model where job LQ is the dependent variable.

Incorporating citizen science into IUCN Red List assessments.

Many citizen scientists are highly motivated to help address the current extinction crisis. Their work is making valuable contributions to protecting species by raising awareness, identifying species occurrences, assessing population trends, and informing direct management actions, such as captive breeding. However, clear guidance is lacking about how to use existing citizen science data sets and how to design effective citizen science programs that directly inform extinction risk assessments and resulting conservation actions based on the International Union for Conservation of Nature (IUCN) Red List criteria. This may be because of a mismatch between what citizen science can deliver to address extinction risk and the reality of what is needed to inform threatened species listing based on IUCN criteria. To overcome this problem, we examined each IUCN Red List criterion (A-E) relative to the five major types of citizen science outputs relevant to IUCN assessments (occurrence data, presence-absence observations, structured surveys, physical samples, and narratives) to recommend which outputs are most suited to use when applying the IUCN extinction risk assessment process. We explored real-world examples of citizen science projects on amphibians and fungi that have delivered valuable data and knowledge for IUCN assessments. We found that although occurrence data are routinely used in the assessment process, simply adding more observations of occurrence from citizen science information may not be as valuable as inclusion of more nuanced data types, such as presence-absence data or information on threats from structured surveys. We then explored the characteristics of citizen science projects that have already delivered valuable data to support assessments. These projects were led by recognized experts who champion and validate citizen science data, thereby giving greater confidence in its accuracy. We urge increased recognition of the value of citizen science data within the assessment process.

Correction: The habitat breadth of phyllostomid bats is partially determined by their diet and could be used as a predictor of extinction risk

Correction: The habitat breadth of phyllostomid bats is partially determined by their diet and could be used as a predictor of extinction risk

Arthropod traits as proxies for abundance trends in the Azorean Islands

Human activities drive ecological transformation, impacting island ecosystems from species diversity to ecological traits, mainly through habitat degradation and invasive species. Using two unique long‐term datasets we aim to evaluate whether species traits (body size, trophic level, dispersal capacity and habitat occupancy) can predict temporal variations in the abundance of endemic, indigenous (endemic and native non‐endemic) and exotic arthropods in the Azores Islands. We found that body size is crucial to predict arthropod abundance trends. Small‐bodied herbivorous arthropods showed a decrease in abundance, while large‐bodied indigenous arthropods increased in abundance, mainly in well‐preserved areas. Also, large‐bodied exotic arthropods increased in abundance across the entire archipelago. Moreover, endemic canopy dwellers increased in abundance, while endemic ground‐dwellers decreased in abundance. Simultaneously, exotic arthropods showed the opposite result, increasing in abundance in the ground while decreasing in abundance in the canopy. Finally, habitat influenced both endemic and exotic spider abundance trends. Endemic spiders that occupy solely natural habitats experienced a decline in abundance, while exotic spiders in the same habitats increased in abundance. Our study underscores the significance of arthropod species traits in predicting abundance changes in island ecosystems over time, as well as the importance of monitoring species communities. Conservation efforts must extend beyond endangered species to protect non‐threatened ones, given the increased extinction risk faced by even common species on islands. Monitoring and restoration programs are essential for preserving island ecosystems and safeguarding endemic arthropod populations.

A new species of the Cambeva variegata group (Siluriformes: Trichomycteridae) from the Serra do Espinhaço, south-eastern Brazil, under severe risk of extinction

The mountain ranges of southeastern and southern Brazil are inhabited by a great diversity of catfishes of the genus Cambeva. The Cambeva variegata group, diagnosed by having a prominent skin crest similar to an adipose fin, an interrupted supraorbital laterosensory canal, with an additional supraorbital S4 pore, and a relatively small premaxilla with an accentuated constriction on its lateral portion, occurs in a broad area of south-eastern Brazil, mostly within the savannah-like Cerrado vegetation at the northern-most part of the genus distribution. The new species described here was collected in streams of the Rio das Velhas drainage, Rio São Francisco basin, draining the Serra do Espinhaço. The new species is diagnosed by having more interopercular odontodes and a combination of morphometric data, colour pattern, relative dorsal-fin origin and vertebra position, and-fin-ray morphology. Field studies indicate that the two localities where the new species occur are being dramatically affected by negative human impacts, putting it in severe risk of extinction.

Large-scale genome sequencing of giant pandas improves the understanding of population structure and future conservation initiatives

The extinction risk of the giant panda has been demoted from "endangered" to "vulnerable" on the International Union for Conservation of Nature Red List, but its habitat is more fragmented than ever before, resulting in 33 isolated giant panda populations according to the fourth national survey released by the Chinese government. Further comprehensive investigations of the genetic background and in-depth assessments of the conservation status of wild populations are still necessary and urgently needed. Here, we sequenced the genomes of 612 giant pandas with an average depth of ~26× and generated a high-resolution map of genomic variation with more than 20 million variants covering wild individuals from six mountain ranges and captive representatives in China. We identified distinct genetic clusters within the Minshan population by performing a fine-grained genetic structure. The estimation of inbreeding and genetic load associated with historical population dynamics suggested that future conservation efforts should pay special attention to the Qinling and Liangshan populations. Releasing captive individuals with a genetic background similar to the recipient population appears to be an advantageous genetic rescue strategy for recovering the wild giant panda populations, as this approach introduces fewer deleterious mutations into the wild population than mating with differentiated lineages. These findings emphasize the superiority of large-scale population genomics to provide precise guidelines for future conservation of the giant panda.

Determining Priority Conservation of Endemic Palms in the Philippine Islands Using a Localized Conservation Priority Index

The mass production of palms for economic and cultural use in the Philippines leads to risk of extinction, genetic erosion, and biodiversity loss. This study aimed to identify top-priority endemic Arecaceae species in the Philippine Islands using a modified localized conservation priority index (LCPI), which considered factors such as distribution, harvesting risk, and economic and cultural use. A taxonomic list of 89 species was constructed, spanning 12 genera, with Calamus being the most speciose genus containing 25 endemic species. The LCPI assessment designated 31 high priority species for conservation, 24 as medium priority, and 34 as low priority. High-priority palms scored highly on the LCPI due to their limited distribution, high susceptibility to overharvesting, and significant economic and cultural value to local communities. The study reveals the diversity and importance of endemic Philippine palms needing urgent conservation efforts to sustain their valuable ecosystem services.

Accelerating and standardising IUCN Red List assessments with sRedList

The IUCN Red List of Threatened Species underpins much decision-making in conservation and plays a key role in monitoring the status and trends of biodiversity. However, the shortage of funds and assessor capacity slows the uptake of novel data and techniques, hampering its currency, applicability, consistency and long-term viability. To help address this, we developed sRedList, a user-friendly online platform that assists Red List assessors through a step-by-step process to estimate key parameters in a standardised and reproducible fashion. Through the platform, assessors can swiftly generate outputs including species' range maps, lists of countries of occurrence, lower and upper bounds of area of occupancy, habitat preferences, trends in area of habitat, and levels of fragmentation. sRedList is compliant with the IUCN Red List guidelines and outputs are interoperable with the Species Information Service (SIS; the IUCN Red List database) in support of global, regional and national assessments and reassessments. sRedList can also help assessors prioritise species for reassessment. sRedList was released in October 2023, with a complete documentation package (including text documentation, ‘cheatsheets’, and 15 video tutorials), and will soon be highlighted in the official Red List online training course. sRedList will help to bridge the gap between extinction risk research and Red List assessment practice, increase the taxonomic coverage and consistency of assessments, and ensure the IUCN Red List is up-to-date to best support conservation policy and practice across the world.

Assessing exploitation vulnerability risk of marine ornamental reef fish in Sri Lanka: A productivity susceptibility analysis

We conducted a Productivity Susceptibility Analysis (PSA) to empirically assess the vulnerability risk of marine ornamental reef fish in Sri Lanka for exploitation. We considered distribution, accessibility, ecological niche, and market price as susceptibility attributes, while fecundity, larval development, maximum length, and longevity were productivity attributes. The vulnerability score, demand, and market price were used to assess species prioritization, and then compositions of the prioritized species were computed. The veracity of primary and secondary data collected on susceptibility and productivity attributes was confirmed by interviewing traditional fishers in situ. The IUCN and present PSA classifications for the medium susceptibility risk species were comparatively assessed. Four species out of 17 medium susceptibility risk species were encountered as the medium vulnerability risk species for exploitation. The Pacific cleaner shrimp (Lysmata amboinensis) emerged as the highest prioritized species. In addition, we observed significant differences in the species’ status assessed through the PSA approach compared to the IUCN status. The study affirms that demand and market prices substantially influence the exploitation vulnerability of species, and the PSA offers a promising multidisciplinary approach to evaluating intrinsic and extrinsic factors in conservation ecology compared to widely used IUCN status for assessing extinction risk. Furthermore, the present findings have practical implications, as they warrant essential policy changes for conserving the prioritized species and the medium vulnerability risk species encountered in the present research to extinction risk.

What does not kill Gaia makes her stronger: impacts of external perturbations on biosphere evolution

ABSTRACT Life on Earth has experienced numerous upheavals over its approximately 4 billion year history. In previous work, we have discussed how interruptions to stability lead, on average, to increases in habitability over time, a tendency we called entropic Gaia. Here, we continue this exploration, working with the Tangled Nature Model of co-evolution, to understand how the evolutionary history of life is shaped by periods of acute environmental stress. We find that while these periods of stress pose a risk of complete extinction, they also create opportunities for evolutionary exploration which would otherwise be impossible, leading to more populous and stable states among the survivors than in alternative histories without a stress period. We also study how the duration, repetition and number of refugia into which life escapes during the perturbation affects the final outcome. The model results are discussed in relation to both Earth history and the search for alien life.

Verifying the Diet of the Slender Racer, <i>Orientocoluber spinalis</i> (Peters, 1866), Rare, Threatened, and Endangered Across Northeast Asian Countries

Understanding the diet of a species provides important information on various aspects of its ecology. Diet studies are few on the reptile species, of which observation frequency is very low, due to the great difficulty of sampling. We investigated the diet of Orientocoluber spinalis, a long and slender small grassland snake with high rarity and a high extinction risk across northeast Asian countries, by applying regurgitated stomach content analysis and metabarcoding analysis using a developed O. spinalis blocking primer. Among 19 diet samples, which were mainly collected on islands along the west coast of the Korean Peninsula, we determined the food sources of 13 samples, which consisted of four small vertebrate species, the Tsushima smooth skink (Scincella vandenburghi), mountain grass lizard (Takydromus wolteri), Japanese keelback (Hebius vibakari), and lesser white-toothed shrew (Crocidura shantungensis). Among them, O. spinalis most frequently fed on S. vandenburghi (10 of 13 cases). Our results show that O. spinalis mainly forages small reptiles and mammals in grasslands adjoining to lowland forests and could be beneficial for conservation in the field and rearing of this vulnerable species in the facilities.

Predicting the climatic suitability of non-native drought resistant trees in the face of desertification – A case study with Argania spinosa in the Iberian Peninsula

Climate change is driving a poleward shift in the optimal distributions of terrestrial organisms, including trees. Consequently, trees are expected to decrease in climatically unfavourable areas as their optimal climatic conditions shift poleward. This is the case of Mediterranean High Nature Value agroforestry systems in Iberian Peninsula, dominated by holm oaks (Quercus rotundifolia) and cork oaks (Quercus suber), which are expected to shift their future distribution northward. Failure to keep pace with climate warming poses a heightened risk of extinction for these tree species, as well as the loss of crucial ecosystem services they provide. A similar situation is found for argan trees (Argania spinosa) in the southwestern region of Morocco, where it also supports an agroforestry system. The optimum climate for these trees is also shifting northward, toward the Iberian Peninsula. As the argan tree thrives in more arid conditions with irregular precipitation, the future climatic conditions in the Iberian Peninsula may become favourable for the persistence of this tree. In light of this situation, the assisted colonization of the argan tree could potentially contribute to protecting and preserving the tree-associated ecosystem services in Iberian Peninsula. We conducted climate suitability modelling using maximum entropy approach, for both the current and future timeframes, for North of Morocco and Algeria (native range) and the whole Iberian Peninsula (non-native range). Accordingly, there appears to be a significant area with highly suitable climatic conditions (>80 %) for argan tree occurrence, covering approximately 6.7 % of the territory, over 38,000 km2. This area is projected to increase significantly in the future, covering 9–22 % of the territory, or about 55,000 and 127,000 km2. With this study, we aim to contribute to the discussion on the benefits of assisted colonization of argan trees into Iberian Peninsula, as well as potential drawbacks such as the risk of this species becoming invasive.

Predicting climate change impact on the habitat of Ethiopia’s spot-breasted lapwing using ensemble model

Endemic species are usually confined in a restricted geographical range with specialized ecological requirements. Majority of these species, therefore, are under the risk of extinction due to climate change coupled with other anthropogenic pressures. The impact is increasingly recognized as severe in tropical highland endemic bird species by either shifting or contracting their geographical range. In this study, we tried to show the impact of climate change on one of Ethiopian highland endemic bird species, the spot-breasted lapwing (Vanellus melanocephalus). Although this species is considered Least Concern, it is restricted in the fragmented Afro-alpine open grassland a long streams or seasonal pond ecosystem of Ethiopia. We predicted the current suitable habitat of this species and projected its future suitable habitat range under two shared socio-economic pathways (SSP4.5 and SSP8.5) of the year 2050 and 2070. We used 117 georeferenced occurrence points and 11 ecologically important variables to develop an ensemble suitable habitat modeling by averaging nine-species distribution algorithms with threshold of TSS > 0.7. The result indicated 104,117.62 km² area as a predicted suitable habitat range in various northwestern and southeastern Ethiopian highlands. The largest range of this suitable habitat (78.02 %) is outside the protected areas of the country. Mean temperature of the driest quarter was the leading bioclimatic variable for the prediction of suitable habitat of this species followed by iso-thermality and vegetation. Habitat suitability declined as mean temperature of the driest quarter is beyond 15ºC. Under future climatic scenarios, substantial suitable habitat loss will occur with more than 50 % of net range size change. This loss of suitable habitat will be 86.60 % under SSP8.5 by the year 2070. Such range contractions suggest the potential risk of extinction of this species in the future unless conservation action is taken. The presence of a large range of current suitable habitat outside of protected areas reveal the need for species-specific conservation plan in both protected and unprotected areas. Moreover, adequate ecological, genetic and geographical studies are also mandatory to have full understanding regarding the impact of climate change and anthropogenic pressure on this endemic bird species in the future.

High extinction risk in large foraminifera during past and future mass extinctions.

There is a strong relationship between metazoan body size and extinction risk. However, the size selectivity and underlying mechanisms in foraminifera, a common marine protozoa, remain controversial. Here, we found that foraminifera exhibit size-dependent extinction selectivity, favoring larger groups (>7.4 log10 cubic micrometer) over smaller ones. Foraminifera showed significant size selectivity in the Guadalupian-Lopingian, Permian-Triassic, and Cretaceous-Paleogene extinctions where the proportion of large genera exceeded 50%. Conversely, in extinctions where the proportion of large genera was <45%, foraminifera displayed no selectivity. As most of these extinctions coincided with oceanic anoxic events, we conducted simulations to assess the effects of ocean deoxygenation on foraminifera. Our results indicate that under suboxic conditions, oxygen fails to diffuse into the cell center of large foraminifera. Consequently, we propose a hypothesis to explain size distribution-related selectivity and Lilliput effect in animals relying on diffusion for oxygen during past and future ocean deoxygenation, i.e., oxygen diffusion distance in body.

Demography and environment modulate the effects of genetic diversity on extinction risk in a butterfly metapopulation

Linking genetic diversity to extinction is a common goal in genomic studies. Recently, a debate has arisen regarding the importance of genetic variation in conservation as some studies have failed to find associations between genome-wide genetic diversity and extinction risk. However, only rarely are genetic diversity and fitness measured together in the wild, and typically demographic history and environment are ignored. It is therefore difficult to infer whether a lack of an association is real or obscured by confounding factors. To address these shortcomings, we analyzed genetic data from 7,501 individuals with extinction data from 279 meadows and mortality of 1,742 larval nests in a butterfly metapopulation. We found a strong negative association between genetic diversity and extinction when considering only heterozygosity in models. However, this association disappeared when accounting for ecological covariates, suggesting a confounding between demography and genetics and a more complex role for heterozygosity in extinction risk. Modeling interactions between heterozygosity and demographic variables revealed that associations between extinction and heterozygosity were context-dependent. For example, extinction declined with increasing heterozygosity in large, but not currently small populations, although negative associations between heterozygosity, extinction, and mortality were detected in small populations with a recent history of decline. We conclude that low genetic diversity is an important predictor of extinction, predicting >25% increase in extinction beyond ecological factors in certain contexts. These results highlight that inferences about the importance of genetic diversity for population viability should not rely on genomic data alone but require investments in obtaining demographic and environmental data from natural populations.

Islands of ice: Glacier‐dwelling metazoans form regionally distinct populations despite extensive periods of deglaciation

AbstractAimGlaciers cover considerable portion of land and host diverse life forms from single‐celled organisms to invertebrates. However, the determinants of diversity and community composition of these organisms remain underexplored. This study addresses the biogeography, population connectivity and dispersal of these organisms, especially critical in understanding during the rapid recession of glaciers and increased extinction risk for isolated populations. By reconstructing the Quaternary biogeographic history of Fontourion glacialis, a widespread in Northern Hemisphere glacier obligate species of Tardigrada, we aim to understand how populations of glacier‐dwelling metazoans receive immigrants, respond to disappearing glaciers and to what extent remaining glaciers can serve as refugia.LocationGlaciers across Svalbard, Scandinavia, Greenland and Iceland.MethodsWe analysed mtDNA (COI gene) variability of 263 F. glacialis specimens collected across the distribution range. Phylogeographic and coalescent‐based approaches were used to detect population differentiation patterns, investigate most likely models of gene flow and test the influences of geographical and climatic factors on the distribution of F. glacialis genetic variants.ResultsOur findings indicate that the distribution of F. glacialis genetic variants is primarily influenced by geographical rather than climatic factors. Populations exhibit a dispersal‐limited distribution pattern, influenced by geographical distance and local barriers, even between neighbouring glaciers. Significantly, the genetic structure within Scandinavia suggests the existence of “southern” glacial or low‐temperature refugia, where F. glacialis may have survived a period of extensive deglaciation during the Holocene climatic optimum (8–5 kyr ago).Main ConclusionThe study uncovers complex metapopulation structures in F. glacialis, with impacts of local barriers, population bottlenecks as well as historical ice sheet fluctuations. It suggests that such populations can endure extended periods of deglaciation, highlighting the resilience of glacial refugia. The study highlights the necessity of understanding the diversity and population structure of ice‐dwelling fauna in both spatial and temporal contexts.

Understanding and achieving species elements in the Kunming-Montreal Global Biodiversity Framework.

The Kunming-Montreal Global Biodiversity Framework was adopted in December 2022 by the parties to the Convention on Biological Diversity. The framework states outcomes for species to be achieved by 2050 in goal A and establishes a range of targets to reduce pressures on biodiversity and halt biodiversity loss by 2030. Target 4 calls for urgent recovery actions for species where the implementation of other targets is insufficient to eliminate extinction risk. We analyze key species elements of goal A and target 4, examine their meaning and clarify implementation needs. We emphasize that target 4 should not be seen simply as the species target, because effective implementation of all targets is essential to achieve the species ambitions in goal A, but, rather, as a target for species that require urgent focused actions and emphasize that an indicator is needed to measure the implementation of urgent management actions. We conclude by considering next steps to identify priorities, undertake further research, make use of resources, ensure cooperation and capacity development.

Predicting Conservation Status of Testudoformes under Climate Change Using Habitat Models.

Climate change promotes variations in distribution ranges, potentially leading to biodiversity loss and increased extinction risks for species. It is crucial to investigate these variations under future climate change scenarios for effective biodiversity conservation. Here, we studied the future distribution ranges of 268 Testudoformes species under climate change using habitat models, specifically species distribution models (SDMs), to assess their conservation status. Our results have indicated that over half of species are projected to experience declines in their potential distribution ranges under two scenarios. In particular, we found that three critically endangered species-Three-striped roofed turtle (Batagur dhongoka), Durango mud turtle (Kinosternon durangoense), and Colombian mud turtle (Kinosternon dunni)-displayed extraction of their distribution ranges and faced extinction under global climate change. Additionally, our analysis revealed that the potential distribution ranges of some species might increase under future climate scenarios. However, these findings must be interpreted with caution as they do not account for other significant factors such as biological invasions, population structure, land-use change, anthropogenic disturbances, and inter-organism interrelationships. Future studies should incorporate these factors to provide a more comprehensive assessment of extinction risks. Our findings suggest that climate change, in conjunction with habitat degradation and human activities, must be considered when assessing the extinction risks of Testudoformes.

Wild silk insect of Simlipal biosphere and its molecular genetic diversity for conservation.

Designated silkworms (Antheraea mylitta D.) are found in the Smilipal Biosphere Reserve (SBR) and consist of four ecological groups. This study examined the genetics of eight ethnic groups from four ecological groups (Modal, Nalia, Bogai and Jata) using RAPD and ISSR markers. The RAPD primer produced 127 bands, of which 41 out of 116 polymorphic regions had a PIC value above 0.45. ISSR markers assigned PIC data values to 57 of 127 polymorphic sites. Cluster analysis revealed genetic differences between ecological populations, with markers separating ecological populations into groups. Low testicles and high genetic diversity indicate that these individuals are at different levels. If adequate protection is not provided, the risk of extinction of ecospecies designed in SBR increases. This study shows that the combined use of RAPD + ISSR markers can improve the results of the technology in identifying different diseases in situations where genomic information is limited.

Landscape genetics of spruce grouse at the trailing edge of the boreal forest

Populations on the periphery of a species range generally occupy marginal or less continuous habitat and can have greater extinction risk than populations in the range‐center. For climate‐sensitive populations on the trailing edge of a species' distribution (i.e. low latitude or low elevation), the effects of climate change are expected to compound these threats, increasing the vulnerability of these populations. The spruce grouse Canachites canadensis is a boreal forest specialist that is expected to experience range contraction at the trailing edge of its range due to climate change. In this study, we investigated the genetic structure, genetic diversity, and connectivity of spruce grouse in Minnesota, along the southeastern range limit in the United States. Clustering algorithms and genetic diversity indices suggested a single continuous population occurred throughout northern Minnesota. We detected no signatures of recent inbreeding or population bottlenecks. We used maximum likelihood population effects modeling and identified coniferous forest land cover and lower average spring temperatures as predictors of gene flow. We used two approaches based on circuit theory to map the potential for gene flow and identified regions of consistently high gene flow in the northwest and northeast of the study area. Omniscape, which incorporated additional parameters representing the likely origins of dispersers and the maximum dispersal distance, suggested a more continuous gene flow landscape than did Circuitscape. Our work highlights the current genetic integrity of one of the largest populations of the eastern subspecies of spruce grouse C. c. canadensis in the United States, identifies key landscape attributes for functional connectivity, and demonstrates complementary approaches of Circuitscape and Omniscape for gene flow mapping.