Species life‐history strategies affect population responses to temperature and land‐cover changes

Human-induced environmental changes have a direct impact on species populations, with some species experiencing declines while others display population growth. Understanding why and how species populations respond differently to environmental changes is fundamental to mitigate and predict future biodiversity changes. Theoretically, species life-history strategies are key determinants shaping the response of populations to environmental impacts. Despite this, the association between species life histories and the response of populations to environmental changes has not been tested. In this study, we analysed the effects of recent land-cover and temperature changes on rates of population change of 1,072 populations recorded in the Living Planet Database. We selected populations with at least 5 yearly consecutive records (after imputation of missing population estimates) between 1992 and 2016, and for which we achieved high population imputation accuracy (in the cases where missing values had to be imputed). These populations were distributed across 553 different locations and included 461 terrestrial amniote vertebrate species (273 birds, 137 mammals, and 51 reptiles) with different life-history strategies. We showed that populations of fast-lived species inhabiting areas that have experienced recent expansion of cropland or bare soil present positive populations trends on average, whereas slow-lived species display negative population trends. Although these findings support previous hypotheses that fast-lived species are better adapted to recover their populations after an environmental perturbation, the sensitivity analysis revealed that model outcomes are strongly influenced by the addition or exclusion of populations with extreme rates of change. Therefore, the results should be interpreted with caution. With climate and land-use changes likely to increase in the future, establishing clear links between species characteristics and responses to these threats is fundamental for designing and conducting conservation actions. The results of this study can aid in evaluating population sensitivity, assessing the likely conservation status of species with poor data coverage, and predicting future scenarios of biodiversity change

Tarifabschluss im öffentlichen Dienst - die große Tarifrechtsreform?

Stellt der Tarifabschluss für Arbeiter und Angestellte von Bund und Kommunen einen Beitrag zum Einstieg in eine umfassende Neustrukturierung des öffentlichen Dienstes dar, oder wurde vor allem an den bisherigen alten Strukturen des öffentlichen Dienstes festgehalten? Für Dr. Thomas Böhle, Vereinigung der Kommunalen Arbeitgeberverbände, wird "das bisherige Tarifrecht … durch ein modernes, leistungsorientiertes und transparentes Tarifrecht ersetzt, das den Anforderungen einer modernen Verwaltung für die Bürgerinnen und Bürger gerecht wird". Auch Dr. Ralf Stegner, Finanzminister des Landes Schleswig-Holstein, sieht positive Elemente: "Der Potsdamer Tarifabschluss vom 9. Februar 2005 ist der erste Baustein zur großen Tarifrechtsreform durch Einführung einer neuen Entgeltordnung, in dem auch die Gewerkschaften durchaus ihre Reformfähigkeit unter Beweis gestellt haben.… Im Detail gibt es aus Ländersicht aber auch kritisch zu hinterfragende Entscheidungen." Weitaus skeptischer ist Prof. Dr. Walter A. Oechsler, Universität Mannheim: "Die Analyse macht deutlich, dass die Tarifreform nicht die große durchgreifende Modernisierung des Tarifrechts im öffentlichen Dienst darstellt." Nach Ansicht von Prof. Dr. Monika Böhm, Universität Marburg, stellt der Tarifvertrag einen wichtigen Beitrag zum Einstieg in eine umfassend erforderliche Neustrukturierung des öffentlichen Dienstes dar, obwohl weitgehend an den bisherigen Strukturen festgehalten wurde.Öffentlicher Dienst, Angestellte, Arbeiter, Tariflohn, Leistungsorientierte Vergütung, Tarifvertrag, Deutschland

Quantifying reliability and data deficiency in global vertebrate population trends using the Living Planet Index

Global biodiversity is facing a crisis, which must be solved through effective policies and on-the-ground conservation. But governments, NGOs, and scientists need reliable indicators to guide research, conservation actions, and policy decisions. Developing reliable indicators is challenging because the data underlying those tools is incomplete and biased. For example, the Living Planet Index tracks the changing status of global vertebrate biodiversity, but taxonomic, geographic and temporal gaps and biases are present in the aggregated data used to calculate trends. However, without a basis for real-world comparison, there is no way to directly assess an indicator's accuracy or reliability. Instead, a modelling approach can be used. We developed a model of trend reliability, using simulated datasets as stand-ins for the "real world", degraded samples as stand-ins for indicator datasets (e.g., the Living Planet Database), and a distance measure to quantify reliability by comparing partially sampled to fully sampled trends. The model revealed that the proportion of species represented in the database is not always indicative of trend reliability. Important factors are the number and length of time series, as well as their mean growth rates and variance in their growth rates, both within and between time series. We found that many trends in the Living Planet Index need more data to be considered reliable, particularly trends across the global south. In general, bird trends are the most reliable, while reptile and amphibian trends are most in need of additional data. We simulated three different solutions for reducing data deficiency, and found that collating existing data (where available) is the most efficient way to improve trend reliability, whereas revisiting previously studied populations is a quick and efficient way to improve trend reliability until new long-term studies can be completed and made available

Accelerating the monitoring of global biodiversity : Revisiting the sampled approach to generating Red List Indices

Abstract Given the current biodiversity crisis, pragmatic approaches to detect global conservation trends across a broad range of taxa are critical. A sampled approach to the Red List Index (RLI) was proposed, as many groups are highly speciose. However, a decade after its conception, the recommended 900 species sample has only been implemented in six groups and trend data are available for none, potentially because this sample is unfeasibly high. Using a broader set of all available data we show that when re-assessments are conducted every 10 years, 200 species (400 in some cases) should be sufficient to detect a RLI trend. Correctly detecting changes in slope still requires samples of 900 species (11,000 in some cases). Sampled assessments can accelerate biodiversity monitoring and complement current metrics, but the time-period between assessments and the approaches? purpose should be carefully considered, as there is a trade-off between sample size and the resulting indices.Peer reviewe

A global analysis of viviparity in squamates highlights its prevalence in cold climates

Aim Viviparity has evolved more times in squamates than in any other vertebrate group; therefore, squamates offer an excellent model system in which to study the patterns, drivers and implications of reproductive mode evolution. Based on current species distributions, we examined three selective forces hypothesized to drive the evolution of squamate viviparity (cold climate, variable climate and hypoxic conditions) and tested whether viviparity is associated with larger body size. Location Global. Time period Present day. Taxon Squamata. Methods We compiled a dataset of 9061 squamate species, including their distributions, elevation, climate, body mass and reproductive modes. We applied species-level and assemblage-level approaches for predicting reproductive mode, both globally and within biogeographical realms. We tested the relationships of temperature, interannual and intra-annual climatic variation, elevation (as a proxy for hypoxic conditions) and body mass with reproductive mode, using path analyses to account for correlations among the environmental predictors. Results Viviparity was strongly associated with cold climates at both species and assemblage levels, despite the prevalence of viviparity in some warm climates. Viviparity was not clearly correlated with climatic variability or elevation. The probability of being viviparous exhibited a weak positive correlation with body size. Conclusions Although phylogenetic history is important, potentially explaining the occurrence of viviparous species in regions that are warm at present, current global squamate distribution is characterized by a higher relative abundance of viviparity in cold environments, supporting the prediction of the “cold-climate” hypothesis. The roles of climatic variation and hypoxia are less important and not straightforward. Elevation probably exerts various selective pressures and influences the prevalence of viviparity primarily through its effect on temperature rather than on oxygen concentration

The Impact of Conservation on the Status of the World\u27s Vertebrates

Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world\u27s vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these. Nonetheless, current conservation efforts remain insufficient to offset the main drivers of biodiversity loss in these groups: agricultural expansion, logging, overexploitation, and invasive alien species

Prevalence of sustainable and unsustainable use of wild species inferred from the IUCN Red List of Threatened Species

Unsustainable exploitation of wild species represents a serious threat to biodiversity and to the livelihoods of local communities and Indigenous peoples. However, managed, sustainable use has the potential to forestall extinctions, aid recovery, and meet human needs. We analyzed species-level data for 30,923 species from 13 taxonomic groups on the International Union for Conservation of Nature Red List of Threatened Species to investigate patterns of intentional biological resource use. Forty percent of species (10,098 of 25,009 species from 10 data-sufficient taxonomic groups) were used. The main purposes of use were pets, display animals, horticulture, and human consumption. Intentional use is currently contributing to elevated extinction risk for 28–29% of threatened or near threatened (NT) species (2752–2848 of 9753 species). Intentional use also affected 16% of all species used (1597–1631 of 10,098). However, 72% of used species (7291 of 10,098) were least concern, of which nearly half (3469) also had stable or improving population trends. The remainder were not documented as threatened by biological resource use, including at least 172 threatened or NT species with stable or improving populations. About one-third of species that had use documented as a threat had no targeted species management actions to directly address this threat. To improve use-related red-list data, we suggest small amendments to the relevant classification schemes and required supporting documentation. Our findings on the prevalence of sustainable and unsustainable use, and variation across taxa, can inform international policy making, including the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, the Convention on Biological Diversity, and the Convention on International Trade in Endangered Species.Fil: Marsh, Sophie M. E.. Colegio Universitario de Londres; Reino UnidoFil: Hoffmann, Michael. The Zoological Society of London; Reino UnidoFil: Burgess, Neil D.. Universidad de Copenhagen; Dinamarca. United Nations Environment Programme World Conservation Monitoring Centre; DinamarcaFil: Brooks, Thomas M.. University of the Philippines; Filipinas. University of Tasmania; Australia. International Union for Conservation of Nature; SuizaFil: Challender, Daniel W. S.. University of Oxford; Reino UnidoFil: Cremona, Patricia J.. International Union for Conservation of Nature; Reino UnidoFil: Hilton Taylor, Craig. International Union for Conservation of Nature; Reino UnidoFil: de Micheaux, Flore Lafaye. Universite de Lausanne; Suiza. Institut Francais de Pondichery; India. International Union For Conservation Of Nature And Natural Resources; SuizaFil: Lichtenstein, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Secretaría de Cultura de la Nación. Dirección Nacional de Cultura y Museos. Instituto Nacional de Antropología y Pensamiento Latinoamericano; ArgentinaFil: Roe, Dilys. International Institute For Environment And Development; Reino UnidoFil: Böhm, Monika. Zoological Society Of London Institute Of Zoology; Reino Unid