Elephant Ear
Elliptio crassidens (Lamarck)

Status: State Endangered (August 1, 1989).

Occurence: Occurs in the Mississippi River and the St.Croix River.

Aid to ID: The black to brown shell is moderately compressed and elongated. Anterior end is rounded and the posterior end is obliquely truncated and sharp. The ventral margin is almost straight and the beak is slightly elevated. The nacre color ranges from salmon to purple. Length to 6 inches (15.2 cm).

Habitat: The black to brown shell is moderately compressed and elongated. Anterior end is rounded and the posterior end is obliquely truncated and sharp. The ventral margin is almost straight and the beak is slightly elevated. The nacre color ranges from salmon to purple. Length to 6 inches (15.2 cm).

Management Considerations: The primary host fish for this species, the skipjack herring, has nearly been eliminated in the upper Mississippi due to locks and dams restricting migration from the Gulf of Mexico. Habitat destruction and river pollution have resulted in mussel declines. Protection of habitat and improvements in water quality along with restriction of dredging, impoundments, sand and gravel mining, and navigational improvements would benefit this species. The development of fish runways to facilitate the movement of host species through or around locks and dams would help to protect the elephant ear. Without a suitable host fish, extirpation is inevitable in Wisconsin and other upper Mississippi states.

The content for this page was originally presented in the Endangered and Threatened Invertebrates of Wisconsin, a free publication available by contacting the Endangered Resources Program.