Foraging fidelity and individual specialisation in a temperate bat Myotis Nattereri

1. Bat populations have declined globally over the last century largely due to anthropogenic change. Many temperate forest species of bat appear loyal to their foraging sites however, conservation of these sites rather than just habitat types is rarely considered and is essential to protect bat populations. It is not clear whether site fidelity in bats is species-specific or a more general trait or why it is exhibited but behaviour patterns could be important for conservation and management objectives. Foraging variation may occur due to ‘individual specialisation’ such that individuals differ significantly in their prey or habitat utilisation, independent of class-effects. If bats do exhibit individuality in their habitat choice, then protection of a mosaic of habitats rather than single preferred habitat per species may be critical to their conservation. 2. The goal here was to determine whether Natterer9s bats show fidelity in their foraging choices and whether they show individual specialisation in their foraging habits. 3. Thirty-four individual bats were tracked for at least one full night, from two different sites. 4. Site fidelity in Natterer9s was consistent across a range of intervals (months and years) despite contrasting seasonal contexts. Individuals repeatedly exploited specific foraging locations and showed individual specialisation in their habitat use which is consistent with the behaviour of a territorial species. 5. Studies designed to inform conservation and management of temperate bats should attempt to maximize the number of individuals from which movement data is sought, whilst ensuring that data represent a coherent and meaningful measure of behaviour such as a single full night. Bat conservation may need to shift from general descriptions of habitat preferences to considering individual specialisation in habitat use. Designing conservation strategies resilient to environmental change might then advocate protecting a mosaic of habitats to preserve the habitat specialisms of many individuals and enhance their productivity rather than advocating the preservation of a single preferred habitat only suited to a few individuals.