Comparison of the Foraging Activity of Bats in Coniferous, Mixed, and Deciduous Managed Forests

Abstract

The aim of this study was to compare the foraging activity of bats in coniferous, deciduous, and mixed forests and to test whether this activity was subject to seasonal variation. Sample points were selected in stands of similar spatial structure in coniferous (Pinus sylvestris L.), in mixed (Pinus sylvestris and Quercus petraea (Matt.) Liebl.), and in deciduous (Quercus petraea) managed forests in western Poland. Bat calls were recorded using automated ultrasound recording devices (Batcorder 3.0, ecoObs, Nürnberg, Germany) during five consecutive nights from May to September in each of the six stands. A total of 4250 bat passes were recorded. Overall, 63.1% of bat passes were identified to species, 31.6% were identified to genus or sonotype group, and 5.3% remained unidentified. In total, eight species of bats and seven sonotype groups were recorded. The dominant species in all types of forests were Pipistrellus pygmaeus (44.5% of recorded bat passes), followed by Nyctalus noctula (10.3%) and Pipistrellus nathusii (5.7%). There were no significant differences in the total activity of bats between the three types of forests; however, high seasonal fluctuations in bat foraging activity were found. This study demonstrates that when coniferous, deciduous, and mixed stands with similar spatial structure are compared, forest type does not affect the foraging activity of bats.