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. 1. Habitat fragmentation is thought to threaten biodiversity, but the response of pollinators to fragmentation is still poorly understood, and research seldom includes pollinator nesting requirements. 2. We investigated pollinator community composition in a highly fragmented oak-savannah ecosystem in south-western British Columbia, Canada. We sampled pollinators in 19 fragments ranging from 0.3 to 31 ha and surrounded by a variety of land-use types, including forest, low-density suburban, and urban neighbourhoods. Pan-trapping and netting surveys captured 4464 bees, flies, and wasps in 138 species and 48 genera. 3. Contrary to expectations, overall species richness did not increase with fragment size. However, ground-nester abundance (not diversity) and cavity-nester diversity (not abundance) were higher in larger fragments, as expected. Floral richness and abundance did not foster pollinator diversity for either guild. Brood parasite responses were complex: host availability (ground-nesting bees) was generally important, richness and abundance increased in fragments with high surrounding road density, and abundance also increased in fragments with other habitat fragments nearby. 4. Responses of different nesting guilds to fragmentation may be related to their use of the landscape surrounding habitat fragments. Some common cavity nesters can nest in fences and gardens, but urban land use may be less hospitable for ground nesters. Brood parasites apparently respond both to host availability and landscape characteristics associated with movement among fragments. 5. Consideration of nesting requirements of pollinators provided some insight into their response to habitat loss in our analysis and should be considered in future studies of fragmentation impacts on pollinator biodiversity. [ABSTRACT FROM AUTHOR]

Biodiversity conservation in urban areas has become increasingly important as cities have expanded to cover larger proportions of landscapes across the world. The careful planning of habitat reserves within urbanized areas has the potential to make significant contributions to regional biodiversity. We surveyed the passerine community in 15 habitat reserves within the Phoenix metropolitan region and explored the relationships between community composition and urban land uses surrounding the reserves. Diversity of different guilds was affected in substantially different ways by reserve characteristics and surrounding urban land use. Guilds responded to land use at all three scales included in the study - 200 m, 1000 m and 2500 m. The responses of four guilds, synanthropic, non-synanthropic, insectivore and feeding generalist, were well predicted by the factors considered here. Reserve characteristics (area, shape, isolation), particularly area, had effects on all four of these guilds with non-synanthropic and insectivore species responding positively to area, while synanthropic and feeding generalist species responded negatively. Land use type surrounding the reserves had significant effects on all of these guilds, except for feeding generalists. High density, high diurnal activity land uses decreased diversity, while medium density, low diurnal activity uses increased the diversity of some guilds, particularly insectivores, probably by providing supplemental habitat. This study provides new evidence from an arid urban landscape that not only reserve characteristics, but also surrounding urban land use should be considered during conservation planning, especially if non-synanthropic or insectivore species are among the targeted species. [ABSTRACT FROM AUTHOR]

• Response of dung beetles to grazing in a Mediterranean steppe and the Alps. • Grazing intensity affects the structure and composition of dung beetle assemblages. • Faunal contrasts were more pronounced in the Alps than in the steppe. • Overgrazing was detrimental to soil-digging species but favoured dung-dwellers. • Dung beetle nesting guilds can be used as indicators of grazing intensity effects. Given the impact of livestock on ecosystems worldwide, it is necessary to understand the effects of grazing practices on biodiversity in order to improve the sustainability of pasture management practices. In a pasture, spatio-temporal variability in livestock activity results in a heterogeneous distribution of defoliation, trampling and excreta. To date, fine-scale analyses of grazing intensity have been rare, and the geographical extent of the studies often limited. In this study, we addressed this gap by analysing the influence of contrasting intra-pasture grazing intensity on the structure and composition of dung beetle assemblages. To do this, we studied a three-level grazing intensity gradient in two distinct bioclimatic contexts, a Mediterranean steppe and the Alps, which also allowed us to determine if dung beetle responses to grazing intensity are related to bioclimatic conditions. The observed dung beetle responses showed an imprint of the bioclimatic context and the local pasture conditions, and species composition and relative abundance showed strong variations along the grazing intensity gradient in both study areas. Species assemblages from the most and least grazed parts of pastures differed strongly. By altering habitat conditions, changing dung availability and modifying competitive interactions, fine-scale heterogeneity in grazing intensity led to substantial variations in the abundance of dung beetle nesting guilds. In both study areas an increase in grazing intensity was detrimental to the largest species and the soil-digging species (which bury dung in underground nests), whereas dung-dwelling species (which reproduce inside dung pads) were favoured. We discuss the combined use of nesting guilds and body mass as potential features to generalize the application of dung beetles as indicators of grazing practices. [ABSTRACT FROM AUTHOR]