Roost and hunting site fidelity of female and juvenile Daubenton's bat Myotis daubentonii (Kuhl, 1817) (Chiroptera: Vespertilionidae)

Abstract

We investigated roosting and hunting site fidelity of Daubenton's bats Myotis daubentonii (Kuhl, 1817) Roosting behaviour and hunting activity over ponds of adult females and juveniles were monitored using radiotelemetry. Eighteen roosts were located, all in natural cavities. The bats occupied a limited number of trees located in a specific and small roosting area. This roost aggregation was not linked to the distribution of hollow trees. Furthermore, whereas all 11 ponds in the study area were exploited by Daubenton's bats, monitored individuals were limited to two ponds to which they showed high fidelity. These two ponds were not the closest to the roosting area. Overall, these results show that at least for the time we conducted our experiment, female and juvenile Daubenton's bats are highly faithful to specific roosting and hunting grounds.

Variability of foraging and roosting activities in adult females of Daubenton’s bat (Myotis daubentonii) in different seasons

“…This area covered some 0.7 km 2 with Vápenka, the roost of initial capture of all radio-tracked bats, located approximately in the centre of this area. Maximal distance to which bats moved between two consecutive roosts was 800 m. Accordingly, Rieger (1996) found a mean distance between the two consecutively used roosts about 600 m, with a maximum of 3,922 m. The distances from day roosts to the nearest foraging sites were up to few hundred meters, i.e., within values reported by other investigators (Nyholm 1965;Swift & Racey 1983;Encarnação et al 2005;Kapfer et al 2008). No interchange of members of resident populations was found during an extensive, long-term ringing study conducted in a two study plots, including our study area and another one, located about 10 km apart (Lučan & Hanák in litt., for details see also Gaisler et al 1979).…”

“…Likewise, Rieger (1996) observed, that roosting areas were confined to particular forest plots with no interchange of individuals among individual plots. Accordingly, Kapfer et al (2008) documented a remarkable fidelity of Daubenton's bats to particular roosting, but also, to foraging areas. She hypothesized a discrete distribution of different groups of Daubenton's bats within her study area.…”

Long-term re-use of tree roosts by European forest bats

“…Last but not least, high fidelity to restricted roosting areas within forest stands was documented in different species of bats (Vonhof and Barclay, 1996;Willis and Brigham, 2004;Kapfer et al, 2007). Based on our results on long-term re-use of tree cavities we suggest such traditional roosting areas may exist for many consecutive years.…”

Bat colony size reduction coincides with clear-fell harvest operations and high rates of roost loss in plantation forest

“…Several bat species use small roosting areas and few roosts (Carter and Feldhamer 2005;Kapfer et al 2007;Nixon et al 2009), which may be located entirely within clear-fell harvested areas. The loss of specific roosts may result in increased energetic costs to bats associated with finding new roosts (Arnold 2007), and the forced use of roosts of poor quality (Sedgeley 2001;Sedgeley and O'Donnell 2004), both of which may reduce survival and reproductive success (Brigham and Fenton 1986;O'Donnell and Sedgeley 2006;Sedgeley 2001;Sedgeley and O'Donnell 2004).…”

“…When rates of either natural or forestry-related roost loss are high, colony sizes may change because of direct losses of bats in harvest operations (Borkin and Parsons 2010) or as the rate of natural replacement of new roosts may not keep up with demand, and bats may have to move into new areas to maintain an array of suitable roosts (Carter and Feldhamer 2005). These movements are likely to be rare because many bat species maintain social groups that have geographically distinct roosting areas (Hillen et al 2010;Kapfer et al 2007;Willis and Brigham 2004) and rarely use the roosts of other social groups (O'Donnell 2000a). Thus, colony sizes will likely decline with harvest operations.…”