© Marcel Burkhardt
Evens, R., A. Jacot, T. Artois, E. Ulenaers, T. Neyens, L. Rappaz, C. Theux, J.‐N. Pradervand & A. Jacot (2021)
Improved ecological insights commission new conservation targets for a crepuscular bird species.
Anim Conserv 24: 457–469.
Knowledge on species’ ecological requirements is the key to an effective evidencebased
conservation. An adaptive approach can refine management recommendations
following the outcomes of previous actions or as improved scientific knowledge
about a species’ ecology becomes available. Following severe population declines
the majority of the Swiss European Nightjar (Caprimulgus europaeus) population
is now restricted to a small core area in the canton of Valais, despite the local
application of evidence-based restoration measures to the breeding habitats. The
habitat use of this crepuscular bird species is presumed to be restricted to semiopen
oak-pine scrublands and rocky steppe. By deploying miniature GPS loggers
we assessed the spatial and habitat selection of 42 individuals (25 individuals in
2018 and 30 individuals in 2019; comprising 13 redeployments between years) in
five study sites in the canton Valais. We highlight the importance of using finescaled
movement data to obtain insight into complex multi-scale habitat requirements
of a species. Nightjars used multiple habitats, indicating the importance of
complementary resources to breed (e.g. open forest and shrub) and to forage (e.g.
semi-extensive grasslands and vineyards). The connectivity between these resources
was influenced by habitat configuration and composition. Given these new insights
for future conservation strategies, our results also suggest that national-level land
use changes, mainly due to agricultural intensification processes, have contributed
to the long-term population declines in Switzerland. We therefore consider our
result in the context of knowledge gaps for species that exploit complementary
habitats and the potential shortcomings for conservation planning on discrete species
showing complex ecological requirements.
keywords: European Nightjar, Switzerland, foraging,ecology, spatial use, habitat selection, home,range, GPS tracking, landscape heterogeneity