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Habitat loss and fragmentation are key drivers of biodiversity loss. However, they are usually confounded, making it difficult to separate fragmentation effects from those of habitat loss. In addition, it has been shown that often fragmentation negatively affects biodiversity only below a certain threshold of habitat amount. We investigated the separate and interactive effects of habitat amount and fragmentation on habitat selection of the woodlark at 10 spatial scales. In southern Switzerland this passerine mainly breeds in ground‐vegetated vineyards, which therefore represent the focal habitat type in this study. Additionally, we investigated land cover, topographic and climatic variables at the same 10 scales to obtain a holistic picture of species‐habitat associations. Habitat selection was analyzed at two hierarchical levels: home range selection within the study area and habitat use within home ranges. Home range selection was strongly driven by an interactive effect of habitat amount and fragmentation: woodlarks avoided fragmented areas if habitat amount was below 20% but exhibited a preference for fragmented areas if habitat amount exceeded this threshold. Both habitat amount and fragmentation most strongly affected habitat use at the 100 m scale. We did not find such interactive effects for habitat use within home ranges. At this level, habitat amount at a 50 m scale influenced woodlark presence positively with no significant effects of fragmentation. Furthermore, woodlarks preferred evenly sloped landscape mosaics interspersed with steppes and groves. Two main insights emerge from our study. First, these results highlight the necessity of studying scale explicit and interactive effects of habitat amount and fragmentation when addressing ecological questions, such as habitat selection in birds. Second, we provide management recommendations for farmers: more vineyards should be vegetated and arranged as disjunct patches where their surface covers more than 20% of the landscape but be aggregated where vegetated area is lower. [ABSTRACT FROM AUTHOR]

Abstract: Understanding the rules of habitat selection and the individual behavioural routines in the home‐range is crucial for developing evidence‐based conservation action. We investigated habitat selection and range use of adult little owls Athene noctua in relation to landscape configuration, habitat structure and resource distribution. We determined the preference of habitat structures by VHF‐telemetry. Large‐ and fine‐scale distribution patterns of voles – the main prey during the breeding season – were assessed by transect counts of signs of vole presence. An experiment using artificial perches was carried out to determine the fine‐scale adjustment of the owls' range use in relation to prey abundance and vegetation height. Habitat selection and resource exploitation by little owls were structured at all spatial levels: (1) at the landscape scale, orchards were highly preferred over other areas. This accords with the patchy large‐scale occurrence of voles, which were absent in cropland, but abundant in orchards and grassland; (2) within home‐ranges, the spatial distribution of voles was highly inhomogeneous and structures with high prey abundance were used over‐proportionally; (3) at the scale of foraging sites, little owls preferred patches with low vegetation over those with high prey abundance, establishing that prey availability is the crux. The results suggest that all levels of habitat selection and range use were related to farming practices and affected by current cultivation. Conservation measures should focus on the conservation and restoration of orchards on the landscape level and habitat management measures should focus on grasslands – the main food providers – by creating a mosaic of patches with short grass and tall grass. Together with other habitat structures providing food resources such as field edges, wildflower areas and structures facilitating access to prey, the quality of habitat patches in terms of food availability may be highly improved. [ABSTRACT FROM AUTHOR]