Adding fossil occupancy trajectories to the assessment of modern extinction risk.

The international trade of threatened marine species as seafood poses significant challenges for biodiversity conservation and undermines global sustainability goals. While illegal fishing contributes to these threats, many national and international policies permit the legal harvest and trade of threatened species, creating a fundamental conflict with conservation objectives.The International Union for Conservation of Nature (IUCN) Red List of Threatened Species provides the world's most comprehensive assessment of species' conservation status and extinction risks. However, threats and species' extinction risks at regional levels can differ significantly from global assessments, leading many countries to develop their own national threatened species lists. For instance, the Orange Roughy is classified as "Vulnerable" on the IUCN Red List in Europe, but listed as "Endangered" under Australia's Environment Protection and Biodiversity Conservation (EPBC) Act.While previous studies have analyzed trade patterns using IUCN listings alone, incorporating national threatened species lists can provide a more complete picture of how international trade affects endangered species. Our research compiles national threatened species lists from around the world to examine how major seafood trading nations engage in trade of species listed as threatened under their own biodiversity conservation policies, and identifies the mechanisms that enable such trade. By analyzing the interaction between national conservation frameworks and international trade patterns, we identify critical gaps where trade practices conflict with domestic species protection policies. Our findings suggest specific targets for strengthening domestic conservation measures and highlight opportunities to better align international trade policies with biodiversity protection and sustainability goals.

Biodiversity indices often combine data from different species when used in monitoring programs. Heuristic properties can suggest preferred indices, but we lack objective ways to discriminate between indices with similar heuristics. Biodiversity indices can be evaluated by determining how well they reflect management objectives that a monitoring program aims to support. For example, the Convention on Biological Diversity requires reporting about extinction rates, so simple indices that reflect extinction risk would be valuable. We developed 3 biodiversity indices that are based on simple models of population viability that relate extinction risk to abundance. We based the first index on the geometric mean abundance of species and the second on a more general power mean. In a third index, we integrated the geometric mean abundance and trend. These indices require the same data as previous indices, but they also relate directly to extinction risk. Field data for butterflies and woodland plants and experimental studies of protozoan communities show that the indices correlate with local extinction rates. Applying the index based on the geometric mean to global data on changes in avian abundance suggested that the average extinction probability of birds has increased approximately 1% from 1970 to 2009.Conectando Índices para el Monitoreo de la Biodiversidad con la Teoría de Riesgo de ExtinciónResumenLos índices de biodiversidad combinan frecuentemente los datos de diferentes especies cuando se usan en los programas de monitoreo. Las propiedades heurísticas pueden sugerir índices preferidos, pero carecemos de medios objetivos para discriminar a los índices con propiedades heurísticas similares. Los índices de biodiversidad pueden evaluarse al determinar qué tan bien reflejan los objetivos de manejo que un programa de monitoreo busca apoyar. Por ejemplo, la Convención sobre la Diversidad Biológica requiere reportar las tasas de extinción, así que los índices que reflejan el riesgo de extinción serían valiosos. Desarrollamos 3 índices de biodiversidad que se basan en modelos sencillos de viabilidad de población y que relacionan el riesgo de extinción con la abundancia. Basamos el primer índice en la media geométrica de la abundancia de especies, y el segundo en una media de poder más general. En el tercer índice integramos la media geométrica y la tendencia. Estos índices requieren los mismos datos que índices previos, pero también se relacionan directamente con el riesgo de extinción. La información de campo sobre mariposas y plantas de bosque, y los estudios experimentales de comunidades protozoarias, muestran que los índices se correlacionan con las tasas locales de extinción. Al aplicar el índice basado en la media geométrica sobre los datos globales de los cambios en la abundancia de aves, sugirió que la probabilidad de extinción promedio de aves ha incrementado aproximadamente 1% desde 1970 hasta 2009.Palabras ClaveÍndice de biodiversidad, media geométrica, medida de la biodiversidad, riesgo de extinción

Comparative lists of species’ extinction risk are increasingly being used to prioritise conservation resources. Extinction risk is most rigorously assessed using quantitative data on species’ population trajectories, but in the absence of such data, assessments often rely on qualitative estimates based on expert opinion of species abundances, distributions and threats. For example, one-third of coral species are classified as threatened and another third as near threatened on the IUCN Red List, despite a lack of data at the population level for the vast majority of species. Since many taxa show a strong correlation between species traits and extinction risk, an alternate approach is to identify traits associated with extinction in other groups and apply them to the taxon of interest. Here, we examine whether life-history traits associated with stress tolerance, fecundity and habitat specialisation are correlated with Red List conservation status in reef corals. We found no relationship between conservation status and life-history traits, suggesting that either traits identified as important predictors of extinction risk in other taxa are not important in corals, or that conservation status does not accurately reflect species’ relative extinction risk. Therefore, using global-scale extinction risk assessments to inform conservation of coral reefs presents a high risk of ‘silent extinctions’ of undescribed species. We argue that the conservation status for the vast majority of coral species should be ‘data deficient’ and is likely to remain so for the foreseeable future, and that the status and trends of coral populations can only be reliably assessed at relatively small scales.

Food web structure affects the extinction risk of species in ecological communities

AimThe current assessment of extinction risk in reef corals by the International Union for Conservation of Nature (IUCN) has been criticized, because coral life‐history traits associated with resilience are not reflected in the conservation status. We aimed to carry out a quantitative assessment of the link between reef coral traits and species extinction risk informed by extinctions of reef corals observed in the fossil record.LocationGlobal.Time periodPlio‐Pleistocene and present day.Major taxa studiedScleractinian reef corals.MethodsWe used morphological traits, phylogenetic information and evidence of extinction during the Plio‐Pleistocene to predict the extinction risk of contemporary reef corals. Our model was trained using 138 Caribbean fossil coral species and an automatic machine learning algorithm. We then used this model to predict the extinction risk of 674 modern coral species.ResultsModel validation confirmed 77% accuracy in predicting extinction risk of fossil corals. Extinction risk predicted by our model showed a near‐random (57%) match with the IUCN conservation status. Our model also suggested that corals in the Least Concern or Near Threatened categories might be at higher risk of extinction than currently believed.Main conclusionsMorphological traits of fossil corals linked to their extinction risk in the Plio‐Pleistocene Caribbean Sea are known to reflect the vulnerability of extant corals. However, the results from our fossil‐calibrated model do not match the IUCN assessment of reef corals, with increased overall extinction risk. This does not necessarily indicate near‐future extinction risk, because fossil extinctions are spread over thousands of years. However, we show the applicability of using fossil data to inform the extinction risk of modern corals and recommend that future assessments of extinction risk of reef corals should consider incorporating the relationship between morphological traits and resilience, calibrated by fossil data, to maximize the utility of the extinction risk assessment.

There has been an increasing number of studies on species extinction because of global warming based on estimations of changes in species distributions. Life cycle impact assessment methods do not have a biodiversity damage factor for global warming that uses the extinction risk index. In this study, a method for determining the extinction risks of individual species per unit CO2 emission was proposed and test calculations of the extinction risks of 216 species of Japanese vascular plants were performed. We also examined the possibility of determining local and global extinction risk factors using this method. This method uses the Expected Increase in the Number of Extinction Species (EINES), which is defined as the inverse of the time to extinction, as the extinction risk index. Procedures for determining the extinction risks of individual species per unit CO2 emission (EINES/species/kg) are as follows. First, based on the base scenario of CO2 emission, a niche-based species distribution model is used to estimate species distribution areas in 2000 and 2100 and calculate the distribution area decrease over 100 years. The number of years before the zero distribution area is then determined by assuming that the decrease is constant. Extinction risk is defined as the inverse of this time. The final step is to determine the extinction risk at specific CO2 emissions in addition to the base emission scenario and divide the difference in the extinction risk by the additional amount of CO2 emissions. The distribution areas of 216 species of Japanese vascular plants having southern distribution limits were estimated to decrease by 40–85% in 100 years. The accuracy of the estimation was sufficient according to the value of area under the curve (AUC). Considering climate models and migration conditions, the extinction risk per unit CO2 emission was estimated between −0.6 × 10−18 and 4.7 × 10−18 (EINES/species/kg). We converted the normalization values of the extinction risk of Japan for the 216 species to compare impact of land use changes and waste processing with that of global warming on the species. We found that global warming has smaller impact compared with land use changes and larger impact compared with waste processing. A method for estimating the extinction risks of species per unit CO2 emission was proposed, and it can be used to determine the local and global extinction risk factors of CO2.

Previous studies show that conservation actions have prevented extinctions, recovered populations, and reduced declining trends in global biodiversity. However, all studies to date have substantially underestimated the difference conservation action makes because they failed to account fully for what would have happened in the absence thereof. We undertook a scenario-based thought experiment to better quantify the effect conservation actions have had on the extinction risk of the world's 235 recognized ungulate species. We did so by comparing species' observed conservation status in 2008 with their estimated status under counterfactual scenarios in which conservation efforts ceased in 1996. We estimated that without conservation at least 148 species would have deteriorated by one International Union for Conservation of Nature (IUCN) Red List category, including 6 species that now would be listed as extinct or extinct in the wild. The overall decline in the conservation status of ungulates would have been nearly 8 times worse than observed. This trend would have been greater still if not for conservation on private lands. While some species have benefited from highly targeted interventions, such as reintroduction, most benefited collaterally from conservation such as habitat protection. We found that the difference conservation action makes to the conservation status of the world's ungulate species is likely to be higher than previously estimated. Increased, and sustained, investment could help achieve further improvements.

Assessing temporal changes in species extinction risk is necessary for measuring conservation success or failure and for directing conservation resources toward species or regions that would benefit most. Yet, there is no long-term picture of genuine change that allows one to associate species extinction risk trends with drivers of change or conservation actions. Through a review of 40 years of IUCN-related literature sources on species conservation status (e.g., action plans, red-data books), we assigned retrospective red-list categories to the world's carnivores and ungulates (2 groups with relatively long generation times) to examine how their extinction risk has changed since the 1970s. We then aggregated species' categories to calculate a global trend in their extinction risk over time. A decline in the conservation status of carnivores and ungulates was underway 40 years ago and has since accelerated. One quarter of all species (n = 498) moved one or more categories closer to extinction globally, while almost half of the species moved closer to extinction in Southeast Asia. The conservation status of some species improved (toward less threatened categories), but for each species that improved in status 8 deteriorated. The status of large-bodied species, particularly those above 100 kg (including many iconic taxa), deteriorated significantly more than small-bodied species (below 10 kg). The trends we found are likely related to geopolitical events (such as the collapse of Soviet Union), international regulations (such as CITES), shifting cultural values, and natural resource exploitation (e.g., in Southeast Asia). Retrospective assessments of global species extinction risk reduce the risk of a shifting baseline syndrome, which can affect decisions on the desirable conservation status of species. Such assessments can help conservationists identify which conservation policies and strategies are or are not helping safeguard biodiversity and thus can improve future strategies.

Trophic interactions affect the population dynamics and risk of extinction of basal species in food webs

The complexity of global anthropogenic change makes forecasting species responses and planning effective conservation actions challenging. Additionally, important components of a species' adaptive capacity, such as evolutionary potential, are often not included in quantitative risk assessments due to lack of data. While genomic proxies for evolutionary potential in at-risk species are increasingly available, they have not yet been included in extinction risk assessments at a species-wide scale. In this study, we used an individual-based, spatially explicit, dynamic eco-evolutionary simulation model to evaluate the extinction risk of an endangered desert songbird, the southwestern willow flycatcher (Empidonax traillii extimus), in response to climate change. Using data from long-term demographic and habitat studies in conjunction with genome-wide ecological genomics research, we parameterized simulations that include 418 sites across the breeding range, genomic data from 225 individuals, and climate change forecasts spanning 3 generalized circulation models and 3 emissions scenarios. We evaluated how evolutionary potential, and the lack of it, impacted population trajectories in response to climate change. We then investigated the compounding impact of drought and warming temperatures on extinction risk through the mechanism of increased nest failure. Finally, we evaluated how rapid action to reverse greenhouse gas emissions would influence population responses and species extinction risk. Our results illustrate the value of incorporating evolutionary, demographic, and dispersal processes in a spatially explicit framework to more comprehensively evaluate the extinction risk of threatened and endangered species and conservation actions to promote their recovery.

The successful implementation of the Convention on Biological Diversity's post‐2020 Global Biodiversity Framework will rely on effective translation of targets from global to national level and increased engagement across diverse sectors of society. Species conservation targets require policy support measures that can be applied to a diversity of taxonomic groups, that link action targets to outcome goals, and that can be applied to both global and national data sets to account for national context, which the species threat abatement and restoration (STAR) metric does. To test the flexibility of STAR, we applied the metric to vascular plants listed on national red lists of Brazil, Norway, and South Africa. The STAR metric uses data on species’ extinction risk, distributions, and threats, which we obtained from national red lists to quantify the contribution that threat abatement and habitat restoration activities could make to reducing species’ extinction risk. Across all 3 countries, the greatest opportunity for reducing plant species’ extinction risk was from abating threats from agricultural activities, which could reduce species’ extinction risk by 54% in Norway, 36% in South Africa, and 29% in Brazil. Species extinction risk could be reduced by a further 21% in South Africa by abating threats from invasive species and by 21% in Brazil by abating threats from urban expansion. Even with different approaches to red‐listing among countries, the STAR metric yielded informative results that identified where the greatest conservation gains could be made for species through threat‐abatement and restoration activities. Quantifiably linking local taxonomic coverage and data collection to global processes with STAR would allow national target setting to align with global targets and enable state and nonstate actors to measure and report on their potential contributions to species conservation.

Abstract. Geographic range has long been acknowledged as an important determinant of extinction risk. The trajectory of geographic range through time, however, has not received as much scientific attention. Here, we test the role of change in geographic range – assessed by a measure of proportional occupancy of grid cells – in determining the extinction risk in four major microplankton groups over the last 66×106 years: foraminifera, calcareous nannofossils, radiolarians, and diatoms. Logistic regression was used to assess the importance of standing occupancy and occupancy change in the extinction risk of species. We find that, while standing occupancy is a major determinant of extinction risk in all microplankton groups, the change in occupancy accounts for an average of 41 % of the explanatory power shared by the two analyzed variables, with a maximum value of 77 %. We also find that, as temporal resolution decreases, the predictive ability of these variables increases. Our results highlight the importance of incorporating both geographic range and its change through time into extinction models. The ability of occupancy trajectory to help predict extinction risk underlines the necessity of paleontological data in modern conservation efforts.

Amphibian populations are declining worldwide and this is causing growing concern. High levels of population declines followed by the expansion of red lists are creating demands for effective strategies to maximize conservation efforts for amphibians. Ideally, integrated and comprehensive strategies should be based on complementary information of population and species extinction risk. Here we evaluate the congruence between amphibian extinction risk assessments at the population level (Declining Amphibian Database––DAPTF) and at species level (GAA––IUCN Red List). We used the Declining Amphibian Database––DAPTF that covers 967 time-series records of amphibian population declines assigned into four levels of declines. We assigned each of its corresponding species into GAA––IUCN red list status, discriminated each species developmental mode, and obtained their geographic range size as well. Extinction risk assessments at the population and species level do not fully coincide across geographic realms or countries. In Paleartic, Neartic and Indo-Malayan realms less than 25% of species with reported population declines are formally classified as threatened. In contrast, more than 60% of all species with reported population declines that occur in Australasia and the Neotropics are indeed threatened according to the GAA––IUCN Red List. Species with aquatic development presented proportionally higher extinction risks at both population and species level than those with terrestrial development, being this pattern more prominent at Australasia, Paleartic, and Neartic realms. Central American countries, Venezuela, Mexico and Australia presented the highest congruence between both population and species risk. We address that amphibian conservation strategies could be improved by using complementary information on time-series population trends and species threat. Whenever feasible, conservation assessments should also include life-history traits in order to improve its effectiveness.

AimBiodiversity hotspots are regions with the highest species richness, and the most threatened species. Previous studies have shown that the extinction risk may be more related to evolutionary history than to species' traits. However, there is a knowledge gap on the relationship between evolutionary history and species extinction risk in biodiversity hotspots. Here, we link evolutionary history to species extinction risk for flowering plants (angiosperms) in global biodiversity hotspots.LocationGlobal biodiversity hotspots.MethodsWe calculated historical evolutionary measures (family species richness, family age, family diversification rate and the ratio of crown age to stem age) of angiosperms from 36 global biodiversity hotspots, which were grouped into 27 regions. Bayesian binomial‐logit univariate and multivariable regression models in conjunction with phylogenetic control and null models were used to identify the evolutionary history predictors of extinction risk for the 27 regions as a whole and for each of the regions.ResultsFamily species richness, family age and family diversification rate are all good indicators for predicting extinction risk. Specifically, when all the 27 regions were considered as a whole, families with higher species richness, older age and/or faster diversification rates have a higher risk of species extinction. However, high extinction risk in some regions, especially in temperate regions, tends to occur in families with low species richness and low diversification rates.Main conclusionsGeographic origin and evolutionary history of species should be jointly taken into account in conservation planning. In general, protection priority should be given to families with high species richness, ancient origins and fast diversification rate because these families seem to be prone to higher extinction risk. Additionally, different strategies should be applied to protect biodiversity in temperate versus tropical regions given that factors affecting extinction risk are different between these regions.

The effect of geographic range and climate on extinction risk in the deep-time amphibian fossil record