Bioacoustic Deterrence of Invasive Bigheaded Carp

Abstract

Since their accidental release into the Mississippi River 30 years ago, invasive bighead and silver carp (Hypophthalmichthys noblis and H. molitrix) comprise a large percent of the biomass in many watersheds throughout the Midwest and Southern regions of the United States. These filter feeding fish, with no natural predators as adults in North America, threaten native species. Local, state, and federal agencies are working to prevent further migration of these invasive species, especially into Lake Michigan, which could open the entire Laurentian Great Lakes system to invasion. One solution currently undergoing evaluation is an acoustic barrier. Controlled experiments in restricted access outdoor ponds outfitted with a cinder-block barrier evaluated the effectiveness of a broadband sound stimulus on fish movement. An acoustic barrier broadcasting a broadband sound was found to be >90% effective in restricting bighead and silver carp movements in a controlled setting. I also tested the impact of this sound on native species which is critical prior to field deployments. The swimming behaviors of native ostariophysians (fathead minnow Pimephales promelas, channel catfish Ictalurus punctatus, bigmouth buffalo Ictiobus cyprinellus), invasive ostariophysians (bighead carp, silver carp, common carp Cyprinus carpio and grass carp Ctenopharyngodon idella), and native non-ostariophysians (paddlefish Polyodon spathula, lake sturgeon Acipenser fulvescens, gizzard shad Dorosoma cepedianum, walleye Sander vitreus, bluegill Lepomis macrochirus, rainbow trout Oncorhynchus mykiss) were monitored in response to broadband sound. Non-bigheaded carp react less to broadband sound and native species do not appear to be impacted by acoustic deterrents using broadband sound.