Population-level sensitivity to landscape variables reflects individual-based habitat selection in a woodland bat species

Abstract

Understanding the relationship between habitat quality and population dynamics is fundamental for long-term management and range predictions in ecology. However, habitat suitability is generally only investigated at the individual scale, as it is the case for the lesser horseshoe bat (Rhinolophus hipposideros), a species of conservation concern. Using a statistical modelling approach and census data of 94 lesser horseshoe bat colonies located in Brittany (France), we analysed the effect of landscape composition and configuration on the demography of surveyed maternity colonies (i.e. colony size, fecundity and growth rate), and compared our result to those provided by individual-based studies. Our results validated that the landscape in a 500meter buffer around colonies (core foraging area) is crucial for population size and dynamics, and confirmed the positive influence of broadleaved woodland proportion on bat colony size. We revealed a positive effect of lakeshores and riverbanks on colony size and growth rate, underlying the importance of these habitats for the long-term conservation of this non-migratory forest species. Importantly, our results refine previous knowledge concerning the threat posed by the intensification of human activities (e.g. urbanization, agriculture, habitat fragmentation), and highlight the negative effect of large and regular patches of artificial and crop lands and of open land patches shape complexity on all demographic variables investigated. Finally, by confirming and specifying the conclusions of previous individual level studies about lesser horseshoe bats' habitat selection and quality requirements, our results support the dependence of population dynamics and associated conservation management to individual behaviour and sensitivity.

Lesser Horseshoe Bat Rhinolophus hipposideros (André, 1797)

“…radio tracking) and presence-absence data have shown that broadleaf woodland is the preferred foraging habitat for this species and strongly predicts the presence and size of colonies (Bontadina et al, 2002;Reiter, 2004a;Reiter et al, 2013;Tournant et al, 2013). The relationship between habitat quality and population dynamics was examined in further detail using detailed monitoring data from 94 colonies of the lesser horseshoe bat in Brittany, France (Jan et al, 2019b). Colony size, fecundity and growth rate were estimated for each colony in 2000-2014.…”

“…These results build upon earlier studies and highlight the sensitivity of this species to deterioration of habitat quality around the colony, whether by urbanisation, agriculture (large open fields of crops) and habitat fragmentation. (Jan et al, 2019b).…”