Winged Mapleleaf takeoff for fall

Hatchery biologists joined partners from the Park Service the Minnesota-Wisconsin Ecological Services Field Office, U.S.G.S., and the University of Minnesota to search for displaying Winged Mapleleaf this year. Over the past 6 years we’ve experienced different patterns of flow and temperature across the fall and this year is different still, with very low water levels and cooler overnight lows. The Winged Mapleleaf responded and have been active early. We found the first female in full display in the shallows early in September. Partners or USFWS biologists have been out on the river at least twice a week since the end of August and we’ll continue until the first of October to confirm that we’ve collected great data about the pattern of reproduction this year. We have many plans for any mussel larvae, from collaborative projects with U.S.G.S., to producing juveniles for our own culture at the hatchery.
By: Megan Bradley


A Winged Mapleleaf in full display. She is ready to infest her host fish. The mantle magazine is the grey protuberance sitting at the center of the white to grey plate of inflated mantle that she will not pull back when disturbed. Her glochidia, or larvae, have been released into her mantle cavity in preparation for a fish mouthing at the magazine. If none arrives they’ll be ejected into the river after a day or so and she’ll burrow back down into the river bottom. Photo credit: Megan Bradley/USFWS.