The status of the world's land and marine mammals: diversity, threat, and knowledge

Knowledge of mammalian diversity is still surprisingly disparate, both regionally and taxonomically. Here, we present a comprehensive assessment of the conservation status and distribution of the world's mammals. Data, compiled by 1700+ experts, cover all 5487 species, including marine mammals. Global macroecological patterns are very different for land and marine species but suggest common mechanisms driving diversity and endemism across systems. Compared with land species, threat levels are higher among marine mammals, driven by different processes (accidental mortality and pollution, rather than habitat loss), and are spatially distinct (peaking in northern oceans, rather than in Southeast Asia). Marine mammals are also disproportionately poorly known. These data are made freely available to support further scientific developments and conservation action

An evaluation of the robustness of global amphibian range maps

AimMaps of species ranges are among the most frequently used distribution data in biodiversity studies. As with any biological data, range maps have some level of measurement error, but this error is rarely quantified. We assessed the error associated with amphibian range maps by comparing them with point locality data. LocationGlobal. MethodsThe maps published by the Global Amphibian Assessment were assessed against two data sets of species point localities: the Global Biodiversity Information Facility (GBIF), and a refined data set including recently published, high-quality presence data from both GBIF and other sources. Range fit was measured as the proportion of presence records falling within the range polygon(s) for each species. ResultsUsing the high-quality point data provided better fit measures than using the raw GBIF data. Range fit was highly variable among continents, being highest for North American and European species (a fit of 84-94%), and lowest for Asian and South American species (a fit of 57-64%). At the global scale, 95% of amphibian point records were inside the ranges published in maps, or within 31km of the range edge. However, differences among continents were striking, and more points were found far from range edges for South American and Asian species. Main conclusionsThe Global Amphibian Assessment range maps represent the known distribution of most amphibians well; this study provides measures of accuracy that can be useful for future research using amphibian maps as baseline data. Nevertheless, there is a need for greater investment in the continuous updating and improvement of maps, particularly in the megadiverse areas of tropical Asia and South America

The status of the world's land and marine mammals: diversity, threat, and knowledge

Knowledge of mammalian diversity is still surprisingly disparate, both regionally and taxonomically. Here, we present a comprehensive assessment of the conservation status and distribution of the world's mammals. Data, compiled by 1700+ experts, cover all 5487 species, including marine mammals. Global macroecological patterns are very different for land and marine species but suggest common mechanisms driving diversity and endemism across systems. Compared with land species, threat levels are higher among marine mammals, driven by different processes (accidental mortality and pollution, rather than habitat loss), and are spatially distinct (peaking in northern oceans, rather than in Southeast Asia). Marine mammals are also disproportionately poorly known. These data are made freely available to support further scientific developments and conservation action

Identifying the world's most climate change vulnerable species: a systematic trait-based assessment of all birds, amphibians and corals

Climate change will have far-reaching impacts on biodiversity, including increasing extinction rates. Current approaches to quantifying such impacts focus on measuring exposure to climatic change and largely ignore the biological differences between species that may significantly increase or reduce their vulnerability. To address this, we present a framework for assessing three dimensions of climate change vulnerability, namely sensitivity, exposure and adaptive capacity; this draws on species’ biological traits and their modeled exposure to projected climatic changes. In the largest such assessment to date, we applied this approach to each of the world’s birds, amphibians and corals (16,857 species). The resulting assessments identify the species with greatest relative vulnerability to climate change and the geographic areas in which they are concentrated, including the Amazon basin for amphibians and birds, and the central Indo-west Pacific (Coral Triangle) for corals. We found that high concentration areas for species with traits conferring highest sensitivity and lowest adaptive capacity differ from those of highly exposed species, and we identify areas where exposure-based assessments alone may over or under-estimate climate change impacts. We found that 608–851 bird (6–9%), 670–933 amphibian (11–15%), and 47–73 coral species (6–9%) are both highly climate change vulnerable and already threatened with extinction on the IUCN Red List. The remaining highly climate change vulnerable species represent new priorities for conservation. Fewer species are highly climate change vulnerable under lower IPCC SRES emissions scenarios, indicating that reducing greenhouse emissions will reduce climate change driven extinctions. Our study answers the growing call for a more biologically and ecologically inclusive approach to assessing climate change vulnerability. By facilitating independent assessment of the three dimensions of climate change vulnerability, our approach can be used to devise species and area-specific conservation interventions and indices. The priorities we identify will strengthen global strategies to mitigate climate change impact

Concentrations of climate change vulnerable species.

<p>Areas with greatest concentrations of species with high sensitivity and low adaptive capacity only are shown in blue, and those with high exposure to climatic change only are in yellow. Areas with high concentrations of species that have high sensitivity and low adaptive capacity species, as well as of highly exposed species, are shown in maroon; they correspond with areas of high overall climate change vulnerability. Total numbers of climate change vulnerable birds, amphibians and corals are shown in A, C and E respectively, while B, D and F show the proportions of species occurring in a region that are climate change vulnerable. Grey areas show where species are present, but concentrations of focal species groups are low; colours increase in intensity as total numbers (for A, C and E) and proportions (for B, D and F) of focal species increase. These results were based on the moderate A1B emissions scenario for 2050 and assume an optimistic scenario for missing trait information.</p

Concentrations of species that are both climate change vulnerable and threatened by non-climate stressors.

<p>Areas with high concentrations of species that are climate change vulnerable only are in yellow, threatened species (according to the IUCN Red List) only are in blue, and areas with high concentrations of both are shown in maroon. The log of total numbers of these birds, amphibians and corals are represented by A, B and C respectively (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0065427#pone.0065427.s006" target="_blank">Figure S6</a> for maps of the proportions of these species relative to species richness). Grey areas show where species are present but concentrations of species that are either climate change vulnerable or threatened are low; colours increase in intensity as species concentrations increase. These results are based on the moderate A1B emissions scenario for 2050 and assume optimistic assumptions for missing trait information.</p

Climate change vulnerability under different emissions scenarios.

<p>Red, black, and blue lines represent the percentages of highly climate change vulnerable species under high (A2), mid-range (A1B) and low (B1) emissions scenarios for birds (A), amphibians (B) and corals (C) for 1975–2050 and 1975–2090. Optimistic and pessimistic estimates for missing biological trait data are represented by solid and dashed lines respectively.</p

Summary of relative climate change vulnerability in birds, amphibians and corals.

<p>This includes the total numbers and percentages of species in the climate change vulnerability categories highlighted in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0065427#pone-0065427-g001" target="_blank">Figure 1</a>, as well as those in each climate change vulnerability dimension alone. To represent the uncertainty resulting from missing biological trait data, vulnerability was calculated assuming optimistic and pessimistic extremes for missing values. It is important to note that scores represent relative measures within each taxonomic groups and comparisons between groups are not meaningful.</p