Minnesota DNR catches, tags silver carp in the St. Croix River

For the first time, state wildlife officials have tagged a silver carp in hopes of learning more about the habits of the invasive fish.

The carp was captured Tuesday in the St. Croix River, about 2 miles south of the Interstate 94 bridge. Department of Natural Resources (DNR) officials found the silver carp, the first of its kind to get a tag, while tracking a tagged bighead carp.

Since carp tend to congregate, the tagged bighead carp already had helped wildlife officials find invasive carp four times this year and twice last year, according to the DNR.

The species poses a threat to the St. Croix's wildlife if it can establish itself and destabilize native fish populations. The discovery of a silver carp doesn't necessarily mean that the river has an established population, officials said.

The unusually high water on the St. Croix and Mississippi rivers this year created open conditions that made it possible for individual fish to swim farther upstream.

Invasive carp species — including silver, grass and bighead — have been found in the Mississippi, St. Croix and Minnesota rivers. All three species have been found as far upstream as the stretch of the Mississippi between the Ford and Hastings dams.

Bighead carp have been found near the King Power Plant on the St. Croix River, as well as just downstream of Granite Falls on the Minnesota River.

The DNR's invasive species program has worked with state and federal government, conservation groups, researchers and businesses to prevent the spread of non-native carp. The Mississippi River lock at upper St. Anthony Falls in Minneapolis was closed in 2015 to prevent carp from swimming upstream of the Twin Cities.

Matt McKinney • 612-673-7329