Promising new acoustic deterrent system being tested in the lab on invasive carp and native fishes

The Sorensen lab at MAISRC is testing a new deterrent system on bigheaded and common carp to identify a set of sensory stimuli that could effectively deter a large number of invasive carp in rivers, without effecting native fish. Thanks to carps’ especially sensitive sense of hearing, sound stimuli are of great interest, but the possibility that other stimuli including air curtains and lights might be synergistic is also being considered. To be useful in navigation locks, deterrent stimuli will have to be highly effective over time and with repeated exposures, as well as safe and species-specific.
An experimental deterrent system has been assembled and is now being tested in the newly renovated MAISRC laboratory. The Sorensen team has already evaluated several types of sound stimuli and found a chirping signal originally identified by an English company to be exceptionally effective for carps, even with repeated exposure. Current research seeks to evaluate species-specificity and enhance deterrence by adding in additional stimuli. This new sound deterrent system could be deployed in navigation locks along with the option of optimizing water velocity through lock and dam spillway gates. Ongoing numeric modeling of water flows though locks and dams also show it to have great promise to stop carp without causing additional scour at lock and dams 2, 4, 5, and 8.
In addition to testing whether this sound system deters invasive carps, this project will test how these acoustic stimuli might impact native fish movement. Bigheaded carp have an exceptional sense of hearing compared to many native species, such as lake sturgeon and walleye, so minimal impacts are expected. The importance of native fishes is addressed by a recently completed invasive carp risk assessment, which urged caution when considering possible prevention and control measures.
This deterrent system adds another piece to the puzzle of invasive carp control, with the overarching goal of producing a sustainable prevention strategy that also promotes the well-being of native ecosystems and fishes in the Mississippi River. Learn more about invasive carps and our research on detecting, preventing, and controlling them here.