Creepy, Invasive Crayfish Confirmed In MN

ALEXANDRIA, MN — Another creepy, invasive species has been discovered in Minnesota.

The Minnesota Department of Natural Resources on Friday said it confirmed the presence of signal crayfish in Lake Winona, located near Alexandria in Douglas County.

Signal crayfish could outcompete native Minnesota species for food and habitat. In addition to being transported by people, the signal crayfish can crawl over land at night and during wet weather.

This is the first confirmation of signal crayfish in Minnesota waters, the DNR said.

A commercial harvester contacted the DNR after trapping two signal crayfish in Lake Winona. Since then, the same harvester has found eight more signal crayfish in the lake.

"Importing live, non-native crayfish to Minnesota is illegal without a permit," DNR Aquatic Invertebrate Biologist Don Eaton said in a news release.

"Regardless of species, it is illegal to release non-native plants or animals into the environment. We deeply appreciate that people harvesting crayfish are keeping a close watch on their catch and that, in this case, the harvester quickly reported this unusual-looking crayfish to the DNR."

Lake Winona. The DNR followed up with trapping in Lake Winona and in two adjacent connected lakes but did not capture additional signal crayfish.

One female was among the 10 adult signal crayfish were captured and removed from Lake Winona, officials said. There is no evidence of reproduction; no eggs or juveniles have been found, according to the DNR.

Signal crayfish are larger and more aggressive than native Minnesota crayfish, officials said. They eat aquatic plants, detritus, fish eggs, smaller crayfish species, and other beneficial native invertebrates, according to the DNR.

People who think they might have found a signal crayfish or other invasive species are urged to report it to the DNR's website.