Working side-by-side with boats and divers, the district and its partners worked as a unified team to place three federally endangered mussel species within the Mississippi River at Pool 2, Aug. 17.
Dan Kelner, the district’s lead mussel biologist, said the team positioned Higgins eye, snuffbox and winged mapleleaf mussels in areas along the river where they once lived. He added that these and other native mussels are critical to the overall ecosystem in the region because they cleanse the water, stabilize the river bottom where they attract other organisms, and they truly are an indicator of good water quality. “They’re the canary in the coal mine,” said Kelner.
Native mussels and many other fish species were nearly wiped out during the first part of the 20th century due to pollution and other activities within the river from Minneapolis to Lake Pepin, near Red Wing, Minn. Phil Delphey, U.S. Fish and Wildlife Service biologist, said the mussel population destruction was caused, in part, by overharvesting for button production and pollution. The river served as the dump for carcasses from slaughter houses, sewage outlets for cities along the river and a collection point for agricultural runoff. “The water quality and the habitat changed so drastically that a lot of these species just disappeared,” said Delphey.
The Mississippi River continued its downward spiral in water quality until the Clean Water Act was passed in 1972. With water quality conditions greatly improved in the area, biologists from the district, U.S. Fish and Wildlife Service, National Park Service and the Illinois, Iowa, Minnesota and Wisconsin Departments of Natural Resources teamed up to place the mussels downstream of Lock and Dam 1 in Minneapolis. Kelner said “We’re just trying to give the federally endangered species, which have been hit particularly hard, a boost.”