Summer distribution of the Pond bat Myotis dasycneme (Chiroptera, Vespertilionidae) in the west of Flanders (Belgium) with regard to water quality

Abstract

The summer distribution of the Pond bat Myotis dasycneme in the west of Flanders was assessed by bat detector surveys and a radiotracking project focusing on hunting activity as well as commuting activity. A preliminary attempt was made to relate hunting activity to water quality data and some field observations of nocturnal insect activity. This study revealed new records of pond bats in the area including a small maternity roost. Recorded activity was high over broad waterways, lower over large ponds and medium sized waterways and very low over small waterways. Pond bats were observed hunting over waterways with different pollution levels from mild to heavier pollution. However more activity was recorded over waterways with mild and moderate pollution than over polluted waterways, whereas Daubenton’s bat Myotis daubentonii was found hunting over all waterways regardless the pollution level.