Individual study: Use of sewage treatment works as foraging sites by insectivorous bats
Park K.J. & Cristinacce A. (2006) Use of sewage treatment works as foraging sites by insectivorous bats. Animal Conservation, 9, 259-268
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Change effluent treatments of domestic and urban waste water
In a replicated, site comparison study between June and August 2003 at 30 sewage treatment works in central and southern Scotland, UK (Park & Cristinacce 2006) significantly higher activity of Pipistrellus spp. was recorded over percolating filter beds than over activated sludge systems (average 15 vs. 4 bat passes/15 min respectively). Foraging activity of Pipistrellus spp. over filter beds was comparable to that at nearby foraging habitat along river banks, whereas foraging activity over activated sludge sites was lower. At filter beds, waste water is sprayed over inert filter material creating a microbial film which supports high insect numbers. In activated sludge systems, sewage and bacterial sludge are mixed together creating an unfavourable habitat for insects. Insect biomass was found to be significantly higher at filter beds. Bat activity was recorded with bat detectors at three points per site for 15 minutes each after dusk, and insects were assessed using suction traps for two hours after dusk at each site. Myotis spp. were also detected at both types of treatment works but numbers were too low for analysis.