A translocation exercise is set to put the BioAcoustic Fish Fence (BAFF) at Kentucky’s Barkley Lock through its paces as a trial of the system continues.

Two lightning strikes delayed progress of the trial, which aims to deter invasive carp from spreading towards the Great Lakes, but the acoustic fish deterrent is now up and running once more

This latest exercise will see 250 of the fish caught and tagged by the United States Geological Survey and the Kentucky Department of Fish and Wildlife Resources.

In the first stage of the translocation exercise, 125 fish will be caught above the lock, then moved below it. The BAFF will be deactivated, and the movement of the fish monitored over the course of a week.

A further 125 fish will then be caught, moved and tracked, this time with the BAFF left operational.

The exercise is intended to mimic the urges of invasive carp in Spring, when they move upstream. The expectation is that a natural instinct to return to where they were caught will see the tagged fish attempt to challenge the BAFF.

If the system is as effective as we expect, far fewer fish from the second group will return upstream.

Previous tests of the BAFF have confirmed success at deterring multiple species of invasive carp in a variety of settings. Laboratory tests at the University of Minnesota showed the BAFF system was 98% effective against bighead carp, and almost 100% successful in deterring common carp.

The system installed at Barkley Lock was inaugurated in 2019 and features Sound Projectors that inject customised signals into an air bubble curtain, with high-intensity lights available for added stimulus.

Of course, the translocation experiment cannot fully replicate the urge that comes from population growth, as invasive species ordinarily move upstream to spawn when more space is needed. There is also a risk that the system becomes inundated as a result of large numbers attempting passage at once, which would not be seen under ordinary circumstances.

However, the FGS team is confident the BAFF will again prove its effectiveness, and we are looking forward to reviewing the results of the exercise in the new year.