Ten-year assessment of the 100 priority questions for global biodiversity conservation

In 2008, a group of conservation scientists compiled a list of 100 priority questions for the conservation of the world's biodiversity ?Sutherland et al. (2009) Conservation Biology, 23, 557?567?. However, now almost a decade later, no one has yet published a study gauging how much progress has been made in addressing these 100 high?priority questions in the peer?reviewed literature. Here we take a first step toward re?examining the 100 questions and identify key knowledge gaps that still remain. Through a combination of a questionnaire and a literature review, we evaluated each of the 100 questions on the basis of two criteria: relevance and effort. We defined highly?relevant questions as those which ? if answered ? would have the greatest impact on global biodiversity conservation, while effort was quantified based on the number of review publications addressing a particular question, which we used as a proxy for research effort. Using this approach we identified a set of questions that, despite being perceived as highly relevant, have been the focus of relatively few review publications over the past ten years. These questions covered a broad range of topics but predominantly tackled three major themes: the conservation and management of freshwater ecosystems, the role of societal structures in shaping interactions between people and the environment, and the impacts of conservation interventions. We see these questions as important knowledge gaps that have so far received insufficient attention and may need to be prioritised in future research

Impact of climate change on communities: revealing species' contribution.

Although climate is known to play an important role in structuring biological communities, high-resolution analyses of recent climatic impacts on multiple components of diversity are still sparse. Additionally, there is a lack of knowledge about which species drive community response to environmental change. We used a long-term breeding bird data set that encompasses a large latitudinal and altitudinal range to model the effect of temperature on spatial and temporal patterns in alpha and beta diversity. We also established a novel framework for identifying species-specific contributions to these macroecological patterns, hence combining two different approaches for identifying climatic impacts. Alpha diversity increased over time, whilst beta diversity declined; both diversity metrics showed a significant relationship with recent temperature anomalies. By partitioning beta diversity, we showed that the decline was predominately driven by changes in species turnover rather than nestedness suggesting a process of replacement by more common species. Using jackknife analyses we identified how individual species influenced the modelled relationships of diversity with temperature and time. Influential species tended to be habitat generalists with moderate to large distributions. We demonstrate that different facets of avian diversity can respond rapidly to temperature anomalies and as a result have undergone significant changes in the last decade. In general, it appears that warming temperatures are driving compositional homogenization of temperate bird communities via range expansion of common generalist species

Rise of the generalists: evidence for climate driven homogenization in avian communities

Aims Biogeographical evidence suggests a strong link between climate and patterns of species diversity, and climate change is known to cause range shifts. However, there is little understanding of how shifts affect community composition and we lack empirical evidence of recent impacts of climate change on the diversity of vertebrates. Using a long-term comprehensive dataset on bird abundance, we explore recent patterns of change in different components of species diversity and avian communities, and postulate a process to explain the observed changes in diversity and specialization. Location Britain. Methods We used Breeding Bird Survey data for Britain from 1994 to 2006 to calculate site-specific diversity and community specialization indices. We modelled these indices using generalized additive models to examine the relationship between local climate and spatial and temporal trends in community metrics and the relationship between changes in diversity and specialization. Results Local temperature was positively associated with alpha diversity, which increased over the study period, supporting empirical and theoretical predictions of the effect of climate warming. Diversity increased in all habitats, but the rate of increase was greatest in upland areas. However, temperature was negatively associated with community specialization indices, which declined over the same period. Our modelling revealed a nonlinear relationship between community specialization and species diversity. Main conclusions Our models of diversity and specialization provide stark empirical evidence for a link between warming climate and community homogenization. Over a 13-year period of warming temperatures, diversity indices increased while average community specialization decreased. We suggest that the observed diversity increases were most likely driven by range expansion of generalist species and that future warming is likely to increase homogenization of community structure. When assessed in combination, diversity and specialization measures provide a powerful index for monitoring the impacts of climate change

Local-scale tree and shrub diversity improves pollination services to shea trees in tropical West African parklands

Shea Vitellaria paradoxa trees bear fruit and seeds of considerable economic, nutritional and cultural value in the African Sudano?Sahelian zone. In much of West Africa, shea exists within an agroforestry system referred to as ?parkland?, where social changes, including migration, have resulted in expanding areas of crop cultivation, reductions in both the area of fallow land and the duration of fallow periods, and reduced diversity of habitats and woody species. Shea benefits strongly from pollination by bees and the loss of Parkland biodiversity may reduce the availability of pollinators, leading to pollen limitation and reductions in fruit yields. We investigated whether shea trees in southern Burkina Faso experienced pollination limitation, and whether local? and landscape?scale diversity were linked to visitation by bees, the degree of limitation observed and the weight of fruit produced. Honeybees Apis mellifera were observed more frequently in diverse sites, whereas non?Apis species were generally widespread but visited trees in greater numbers at diverse sites. We found that shea fruit production was significantly limited due to lack of pollination and that the degree of pollination limitation was greater in sites with lower levels of tree and shrub diversity. Synthesis and applications . Sites with greater diversity of tree and shrub species had more bee visits and less extreme pollination limitation than less diverse sites, indicating that small?scale diversity is associated with more efficient pollination services. Consequently, shea yields are likely to benefit from retention of a range of different tree and shrub species in parklands. We recommend that when fallows are cleared for cultivation, such beneficial plants are retained within cultivated fields, and that measures to conserve pollinators in the region should target both A. mellifera and non?Apis bee species

Patterns and causes of covariation in bird and butterfly community structure

Context: Variation in biological communities is used to identify biodiversity responses to anthropogenic drivers, and to guide conservation responses. Often, such data are only available for a limited group of species, with uncertain applicability to unmonitored taxa. Objective: Using equivalent data on the community structure of two contrasting taxa, we examine spatial co-variation in both communities, and test the extent to which any associations may result from large-scale latitudinal patterns, variation in habitat-type, or other factors. Methods: Birds and butterflies were surveyed using standard methods across a stratified random sample of 1-km2 squares across the UK. Four measures of community structure were calculated and used to examine their association between the two taxa, before accounting for effects of latitude, habitat-type and observer. Results: Species richness, diversity and community specialisation were significantly correlated between birds and butterflies, but evenness was not. There were strong latitudinal gradients in bird community specialisation, and butterfly richness and diversity. Habitat diversity significantly affected bird communities, whilst butterfly evenness and specialisation was reduced on farmland and human-related habitats. Covariation in richness and diversity between taxa remained after including effects of latitude and habitat-type. Conclusions: Surrogacy approaches may be useful when considering fine-scale variation in species richness and diversity to inform site-based conservation and management decisions. However, limited covariance in evenness and specialisation metrics suggest that decisions based on the needs of rare or specialist species may be less relevant to other taxa