This study addressed solutions for the population control of invasive Procambarus clarkii (Red Swamp Crayfish) in Michigan. The infestation was reported to the Michigan Department of Natural Resources in 2015. P. clarkii outcompetes native species of crayfish, is highly fecund and causes bank erosion through burrowing. Intensive trapping allows slowing the spread of the population and detecting new spread, but the practice is costly. In this study, auditory stimuli were tested as a means of affecting a locomotive response in P. clarkii. These trials tested various pure tone sounds and pink and white noise ranges in artificial habitats. Following those results, a white noise frequency band was played underwater during the trapping season. The results indicated that a high frequency range of white noise (10-15 kHz) was most effective at eliciting a locomotory response. When used during the trapping season, a combination of sound and food bait performed at the highest capture per unit effort (CPUE), 0.820. Traps with only food and only sound performed at 0.644 and 0.675, respectively. Moreover, traps without sound or food bait performed at a high baseline CPUE of 0.487. Artificial refuge traps performed at a higher CPUE than other trap types, despite the lack of food bait. The results suggest that the benefits of refuge, sound, and food bait are additive. A novel trap design was created using the advantages of artificial refuge, food bait, and acoustic stimuli. The implications of this study span from the control of invasive species in the Great Lakes region to increasing profits of crayfish farming in the southern United States.
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