The bloom formed that July around the mouth of the Maumee River, on the lake's western end near Toledo, Ohio.

WSJ: Report predicts ever-bigger Lake Erie algae blooms

Authorities have built a fence in the Fort Wayne area to prevent the carp from migrating from the Wabash to the headwaters of the Maumee River, a Lake Erie tributary regarded as ideal spawning habitat.

WSJ: Asian carp spawning areas wider than expected