Putting the fear of bass into mosquitofish—with a robot

Enlarge / The Robo-bass, along with some actual fish. (credit: Giovanni Polverino)

The mosquitofish is a particularly troublesome invasive species that has spread from its original home in North America to various locales around the world, including Europe and Australia. The small, 3 cm-long fish likes to chew the tails off fish and tadpoles and consume the eggs of other freshwater denizens.

Being an invasive species, the fish are mostly fearless, and they have no predators in the places they’ve colonized. However, an international team of biologists and engineers has found a solution to the problem: the robot.

Back in 2019, Giovanni Polverino—currently a post-doc at the University of Western Australia—and his colleagues developed a new mechanical largemouth bass that proved to be effective in scaring mosquitofish. In North America, juvenile largemouth bass regularly make meals of the species; the primal fear of this predator has stuck with the mosquito fish as they traversed the globe.