Montana Field Guide

The Mapleleaf is a relatively common mussel in the Missouri and Mississippi River drainage's of North America, and has been recently introduced into MT's Tongue River and Lower Yellowstone River, likely from catfish or crappie stocking. It can be found as far south as the Tennessee River, throughout the Midwest and Plains States (native in SD, ND). The Mapleleaf prefers pools of sluggish streams with a mud, sand, or fine gravel bottom. Known host fish species include the Common Carp, Catfish, Green Sunfish, White Crappie, 3 of these 4 species are introduced or exotic species in Montana. Mapleleafs have a fairly thick shell with well-developed teeth. Squared in outline, lateral surface with two rows of pustules separated by a sulcus.

Sedentary as adults, rarely move more than a few meters. As larvae (glochidia on the fish gills), they use their fish host for disperal upstream or downstream to other suitable habitats.

Medium to large rivers and reservoirs with a mud, sand, or gravel bottom.

Freshwater mussels are mostly filter-feeders, siphoning in floating particulate organic materials (small plant or animal) from the water column and straining out the particles and expel the strained water. Pedal feeding with the foot muscle has also been observed, mostly in juveniles and younger age-classes.

Threats to freshwater mussels and their habitats are thought to include: Pollution, Diversion of rivers for irrigation, hydroelectric and water supply projects, Elimination of natural fish hosts, Eutropification due to agricultural runoff and urbanization