A non-physical deterrent in the field: Variation in avoidance across species

Session: Invasive Species (1)

Paul Bzonek, University of Toronto Scarborough, [email protected]
Nicholas Mandrak, Biological Sciences, University of Toronto Scarborough, [email protected]

Abstract

Non-physical deterrents can be used in conservation to limit the dispersal of invasive fishes without altering hydrological conditions in a watershed. To determine how native and non-native species interact with non-physical deterrents, acoustic and stroboscopic stimuli were deployed alongside a physical Common Carp-exclusion barrier (Royal Botanical Gardens, May - July 2018). Adult fishes migrating into a wetland habitat (Cootes Paradise, Hamilton, Lake Ontario) were blocked by the Common Carp-exclusion barrier and guided towards a series of traps. Two underwater speakers and five strobe-lights were installed over two traps and activated on alternating days for a period of 24 hours. Over 10,000 fish were captured including Brown Bullhead, Common Carp, Gizzard Shad, Goldfish, White Sucker, and Channel Catfish. Preliminary general linear models indicate that the trapping rates of adult fish varied according to species and stimulus activation. This research will help inform management decisions regarding invasive fish exclusion efforts.