Endangered Species
Midwest Region



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White Cat's Paw (Epioblasma obliquata perobliqua)


photo of white cat's paw pearlymussel


As a filter feeder, this mussel siphons gallons of water each day to extract food from the river - and in the process, concentrates poisonous pesticide and fertilizer runoff in its body tissues.


Status: Endangered


Habitat: This mussel prefers coarse sand or gravel bottoms of small to mid-sized freshwater streams and rivers. It prefers shallow water and requires a swift current to avoid being buried in silt.


Behavior: Reproduction requires a stable, undisturbed habitat and a sufficient population of fish hosts to complete the mussel's larval development. When the male discharges sperm into the current, females downstream siphon in the sperm in order to fertilize their eggs, which they store in their gill pouches until the larvae hatch. The females then expel the larvae. Those larvae that manage to attach themselves to the gills of a host fish grow into juveniles with shells of their own. At that point they detach from the host fish and settle into the streambed, ready for a long (possibly up to 50 years) life as an adult mussel.


Why It's Endangered: Intensive agricultural practices have increased erosion and topsoil runoff, smothering mussels in their streambeds. Pesticides and fertilizers in runoff have also poisoned these filter-feeding animals.


With only one known population, the white cat's paw pearly mussel is one of the most critically endangered animals. Recovery may be impossible.


Back to Freshwater Mussels


Last updated: October 10, 2018