Development of an acoustic trap for potential round goby (Neogobius melanostomus) management

Abstract

Abstract Round goby ( Neogobius melanostomus ) is one of the most prolific invasive species ever recorded in the Laurentian Great Lakes and has spread to all five Great Lakes and many of their surrounding waterways since their introduction. While elimination of this invasive species is not possible for all affected waters, control mechanisms are needed to mitigate impacts to vulnerable spawning grounds and slow the spread into new habitats. Here we report on a potential control mechanism exploiting one aspect of the species' sensory ecology, its propensity to swim selectively toward sources of species-specific vocalizations. We deployed a trap containing a speaker broadcasting round goby reproductive calls (grunts) and compared catch efficacy to silent traps and those broadcasting round goby aggression calls (drums). Traps playing the reproductive call caught more round gobies than traps playing either the silent or aggressive calls, with the largest difference seen in May, before water temperatures got too warm for round goby reproduction at our shallow study site. Within the grunt traps, females and non-reproductive males were caught more frequently than spawning males and other species were captured at very low rates. Taken together, these results represent a proof-of-concept that acoustic traps may be viable for round goby control in vulnerable areas while not reducing native species numbers. While we are not arguing that acoustic traps will significantly reduce round goby populations throughout their range, they do represent a low-impact method for protecting vulnerable habitats and may be deployed to measure establishment of spawning populations in new areas.