Wildlife Research Wildlife Research Society
Ecology, management and conservation in natural and modified habitats

Effect of lights on activity levels of forest bats: increasing the efficiency of surveys and species identification

Maria D. Adams A C , Bradley S. Law B and Kris O. French A

A Institute for Conservation Biology, School of Biological Sciences, University of Wollongong, NSW 2522, Australia.

B Research and Development, Forests New South Wales, Department of Primary Industries, PO Box 100, Beecroft, NSW 2119, Australia.

C Corresponding author. Email: maria@uow.edu.au

Wildlife Research 32(2) 173-182 http://dx.doi.org/10.1071/WR04060
Submitted: 14 July 2004  Accepted: 7 February 2005   Published: 4 May 2005


We investigated the effects of insect-attracting ultraviolet lights on activity of forest bats (Microchiroptera) with the prediction that lights would increase our indices of bat activity and improve species identification of recorded echolocation calls. Insect aggregations were created on forest tracks (n = 9) near Kioloa, New South Wales, using three vertically stratified insect light traps. Bat echolocation calls were recorded using a ground-based vertically oriented Anabat II detection system. Bat activity and foraging rates were higher at lit points than at unlit points, particularly when the lights were operated in full darkness. More species were identified at lit points and the sampling time required to identify the second to the fifth new species was 3.3–4.6 times shorter with lights. The presence of lights resulted in a greater number of bat passes more than five pulses in length, which was associated with an increased ability to identify passes to species level. Our study demonstrates that the use of lights in forest-based echolocation surveys can improve bat species inventories, particularly in communities where overlap in call characteristics among species is common.


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