Action to reduce anthropogenic impact on the environment and species within it will be most effective when targeted towards activities that have the greatest impact on biodiversity. To do this effectively we need to better understand the relative importance of different activities and how they drive changes in species’ populations. Here, we present a novel, flexible framework that reviews evidence for the relative importance of these drivers of change and uses it to explain recent alterations in species’ populations. We review drivers of change across four hundred species sampled from a broad range of taxonomic groups in the UK. We found that species’ population change (~1970–2012) has been most strongly impacted by intensive management of agricultural land and by climatic change. The impact of the former was primarily deleterious, whereas the impact of climatic change to date has been more mixed. Findings were similar across the three major taxonomic groups assessed (insects, vascular plants and vertebrates). In general, the way a habitat was managed had a greater impact than changes in its extent, which accords with the relatively small changes in the areas occupied by different habitats during our study period, compared to substantial changes in habitat management. Of the drivers classified as conservation measures, low-intensity management of agricultural land and habitat creation had the greatest impact. Our framework could be used to assess the relative importance of drivers at a range of scales to better inform our policy and management decisions. Furthermore, by scoring the quality of evidence, this framework helps us identify research gaps and needs.

Aim Parental care improves the survival of offspring and therefore has a major impact on reproductive success. It is increasingly recognized that coordinated biparental care is necessary to ensure the survival of offspring in hostile environments, but little is known about the influence of environmental fluctuations on parental cooperation. Assessing the impacts of environmental stochasticity, however, is essential for understanding how populations will respond to climate change and the associated increasing frequencies of extreme weather events. Here we investigate the influence of environmental stochasticity on biparental incubation in a cosmopolitan ground‐nesting avian genus. Location Global. Methods We assembled data on biparental care in 36 plover populations (Charadrius spp.) from six continents, collected between 1981 and 2012. Using a space‐for‐time approach we investigate how average temperature, temperature stochasticity (i.e. year‐to‐year variation) and seasonal temperature variation during the breeding season influence parental cooperation during incubation. Results We show that both average ambient temperature and its fluctuations influence parental cooperation during incubation. Male care relative to female care increases with both mean ambient temperature and temperature stochasticity. Local climatic conditions explain within‐species population differences in parental cooperation, probably reflecting phenotypic plasticity of behaviour. Main conclusions The degree of flexibility in parental cooperation is likely to mediate the impacts of climate change on the demography and reproductive behaviour of wild animal populations.

Recent global assessments of environmental change highlight human-driven loss of biodiversity and the degradation of ecosystem integrity (Díaz et al., 2019; Secretariat of the Convention on Biological Diversity, 2020). Further, they point to a failure to achieve existing biodiversity targets and call for transformative change across sectors of human society as an emerging Post-2020 Global Biodiversity Framework takes shape (https://www.cbd.int/).Yet at the same time, debate continues as to the nature and extent of biodiversity decline (e.g.,

1. Aggregated species occurrence and abundance data from disparate sources are increasingly accessible to ecologists for the analysis of temporal trends in biodiversity. However, sampling biases relevant to any given research question are often poorly explored and infrequently reported; this can undermine statistical inference. In other disciplines, it is common for researchers to complete 'risk-ofbias' assessments to expose and document the potential for biases to undermine conclusions. The huge growth in available data, and recent controversies surrounding their use to infer temporal trends, indicate that similar assessments are urgently needed in ecology.2. We introduce ROBITT, a structured tool for assessing the 'Risk-Of-Bias In studies of Temporal Trends in ecology'. ROBITT has a similar format to its counterparts in other disciplines: it comprises signalling questions designed to elicit information on the potential for bias in key study domains. In answering these, users will define study inferential goal(s) and relevant statistical target populations. This information is used to assess potential sampling biases across domains relevant to the research question (e.g. geography, taxonomy, environment), and how these vary through time. If assessments indicate biases, then users must clearly describe them and/or explain what mitigating action will be taken.3. Everything that users need to complete a ROBITT assessment is provided: the tool, a guidance document and a worked example. Following other disciplines, the tool and guidance document were developed through a consensus-forming process across experts working in relevant areas of ecology and evidence synthesis.

We describe the development of two complementary priority species indicators (PSIs) to help the UK to report progress towards Aichi target 12 on the status of known threatened species. Based on species identified as national conservation priorities, the indicators present average changes in (i) 213 species for which trends in relative abundance are available from structured monitoring schemes, and (ii) 179 species for which trends in frequency of occurrence were modelled from data sets of unstructured biological records. Both indicators show substantial declines in priority species since 1970, of 67% and 40%, respectively, although the rate of decline in the relative abundance-based PSI may have lessened over the last five years (2007)(2008)(2009)(2010)(2011)(2012). We discuss the biases and weaknesses of the indicators at present, and put forward suggestions as how these may be addressed, including through the development of a third PSI.

Summary1. Invasive non-native species are one of the greatest drivers of the loss of biodiversity world-wide. Consequently, removing or controlling invasive predators should generally benefit vulnerable native species. However, especially on islands, where most mammalian predators are introduced, these predators may also prey on other invasive mammals. Removing only apex predators may lead to increases of meso-predators that may in turn increase predation pressure on native wildlife. 2. We examined the benefits of a feral cat Felis catus control programme on nest survival of a critically endangered ground-nesting bird, the St Helena Plover Charadrius sanctaehelenae in two habitat types, harbouring c. 30% of the global population of this species. We monitored nest success and the activity of introduced mammals (cats, rabbits Oryctolagus cuniculus, rats Rattus rattus and Rattus norvegicus, and mice Mus musculus) over 2 years, before and after controlling feral cats. 3. Live trapping removed 56 feral cats from our study areas. In the semi-desert, rabbit and mouse activity increased, but rat activity remained low after feral cat control. In pastures, rat and mouse activity increased after feral cat control, while rabbit activity remained constant. 4. Nest survival of plovers increased more than threefold in the semi-desert, but increased only marginally in pastures. This difference may be due to an increase in rat activity and potentially rat predation following cat control in pastures, whereas no increase in rat activity was observed in the semi-desert. 5. Synthesis and applications. Our study shows habitat-specific consequences of feral cat control on ground-nesting bird productivity after 1 year, probably mediated by differences in the availability of alternative prey. The results highlight the importance of experimental trials and a thorough understanding of the interactions between multiple invasive species before predator-control operations are implemented over larger scales. On islands with multiple invasive species, there may not be a simple generic approach to predator management (other than removing all invasive species simultaneously).

1. Bat populations are thought to have suffered significant declines in the past century throughout Europe. Fortunately, there are some signs of recovery; for instance, of the 11 species monitored in the UK, population trends of five are increasing. The drivers of past losses and recent trends are unclear; identifying them will enable targeted conservation strategies to support further recovery. 2. We review the evidence linking proposed drivers to impacts on bat populations in Europe, using the results of a previous cross-taxa semi-quantitative assessment as a framework. Broadly, the drivers reviewed relate to land-use practices, climate change, pollution, development and infrastructure, and human disturbance. We highlight where evidence gaps or conflicts present barriers to successful conservation and review emerging opportunities to address these gaps. 3. We find that the relative importance or impacts of the potential drivers of bat population change are not well understood or quantified, with conflicting evidence in many cases. To close key gaps in the evidence for responses of bat populations to environmental change, future studies should focus on the impacts of climate change, urbanisation, offshore wind turbines, and water pollution, as well as on mitigation measures and the synergistic effects of putative drivers. 4. To increase available evidence of drivers of bat population change, we propose utilising advances in monitoring tools and statistical methods, together with robust quantitative assessment of conservation interventions to mitigate threats and enable the effective conservation of these protected species.

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