0000000000129477
AUTHOR
Frédéric Jiguet
Weak effects of geolocators on small birds: A meta-analysis controlled for phylogeny and publication bias
Abstract Currently, the deployment of tracking devices is one of the most frequently used approaches to study movement ecology of birds. Recent miniaturization of light‐level geolocators enabled studying small bird species whose migratory patterns were widely unknown. However, geolocators may reduce vital rates in tagged birds and may bias obtained movement data. There is a need for a thorough assessment of the potential tag effects on small birds, as previous meta‐analyses did not evaluate unpublished data and impact of multiple life‐history traits, focused mainly on large species and the number of published studies tagging small birds has increased substantially. We quantitatively reviewe…
Consistent response of bird populations to climate change on two continents
Global climate change is a major threat to biodiversity. Large-scale analyses have generally focused on the impacts of climate change on the geographic ranges of species, and on phenology, the timing of ecological phenomena. Here, we use long-term monitoring of the abundance of breeding birds across Europe and the USA to produce, for both regions, composite population indices for two groups of species: those for which climate suitability has been either improving or declining since 1980. The ratio of these composite indices, the Climate Impact Indicator (CII), reflects the divergent fates of species favored or disadvantaged by climate change. The trend in CII is positive and similar in the …
Covariation in population trends and demography reveals targets for conservation action
Wildlife conservation policies directed at common and widespread, but declining, species are difficult to design and implement effectively, as multiple environmental changes are likely to contribute to population declines. Conservation actions ultimately aim to influence demographic rates, but targeting actions towards feasible improvements in these is challenging in widespread species with ranges that encompass a wide range of environmental conditions. Across Europe, sharp declines in the abundance of migratory landbirds have driven international calls for action, but actions that could feasibly contribute to population recovery have yet to be identified. Targeted actions to improve condit…
ESM for Covariation in population trends and demography reveals targets for conservation action
Supplementary methods, results and JAGS code
Impacts of agricultural intensification on bird communities: New insights from a multi-level and multi-facet approach of biodiversity
International audience; Following the multiplicity of studies dealing with the effects of agricultural intensification on bird diversity, one of the lessons drawn is that these effects depend on both the taxonomic group, the component of diversity, the aspect of intensification, and the spatial scale. This often leads to disparate results among studies suggesting that the investigation of agriculture-biodiversity relationships suffers from scale-dependence, information redundancy, non-linearity problems, and thus, unpredictability.Here, we propose a multi-scale and multi-facet approach to clarify the impacts of agricultural intensification on biodiversity and possible mitigating actions. Ou…
Pesticide doses, landscape structure and their relative effects on farmland birds
International audience; tAgricultural changes related to the intensification of farming practices and the simplification of land-scape elements often occur simultaneously. Their respective effects on biodiversity are thus difficult todisentangle and are poorly understood. This study assessed the relative contribution of each componentof agricultural intensification on taxonomic and functional bird communities.The bird communities studied were composed of 70 species, both farmland and non-farmland birds,found in 66 fields covering three main cereal departments of France. Herbicide dose was related to mea-surable negative effects on the Community Specialization Index (CSI). Overall, the propo…
Effects of Natura 2000 on nontarget bird and butterfly species based on citizen science data
The European Union's Natura 2000 (N2000) is among the largest international networks of protected areas. One of its aims is to secure the status of a predetermined set of (targeted) bird and butterfly species. However, nontarget species may also benefit from N2000. We evaluated how the terrestrial component of this network affects the abundance of nontargeted, more common bird and butterfly species based on data from long-term volunteer-based monitoring programs in 9602 sites for birds and 2001 sites for butterflies. In almost half of the 155 bird species assessed, and particularly among woodland specialists, abundance increased (slope estimates ranged from 0.101 [SD 0.042] to 3.51 [SD 1.30…
Declining populations of European mountain birds
Mountain areas often hold special species communities and are thus in the high priority list of conservation. Changes in human land use, such as grazing pressure and afforestation, and especially in climate have been suggested as major threats for biodiversity in the mountain areas, because species have difficulties to find new suitable habitats in circumstances. Despite the special species communities very little is known about the population trends of species in mountain areas [1,2]. Here we studied population trends of 44 bird species in four major European mountain regions: Fennoscandia, UK upland, south-western (including Pyrenees) and south-central mountains (including Alps), covering…