Description: Very small - at eight and one-half to nine and one-half inches – the interior least tern has a black cap and black line through the eye when in breeding plumage. They have a deep forked tail with the outer tail feathers being white. During winter the adults have a blurred head pattern with mixed black and white feathers.
Habitat and Habits: The interior lease tern, like the piping plover, nests on sandbars and barren areas along rivers. The nests are shallow depressions. The normal clutch size is three eggs. The interior least tern usually nests in small colonies. Nesting occurs from early June through early August. Incubation is about 20 days and the chicks fledge about 20 days after hatching. Terns feed on small fish and crustaceans
Photographer: Wayne Hathaway
Distributions: Nesting occurs in a broad portion of the central United States. In Iowa the interior least tern currently nests at two sites – one near Council Bluffs and one near Sioux City. Both sites are fly-ash deposits from power plants.
Conservation Efforts: MidAmerican Energy Company has worked with the Iowa Department of Natural Resources to protect the Iowa nesting areas on their property. Monitoring of nesting success has helped to identify additional protection measures for the areas.
Reason for Listing: The loss of nesting habitat along rivers due to construction of reservoirs, channelization and changes in water flows has caused the decline. Construction of dams for irrigation and navigation has inundated nesting habitat and altered natural flows of the river. Previously, periodic flooding in the spring built new sandbars, and water levels dropped prior to nesting. Disturbance by people and domestic animals has also contributed to reduced nesting success.
Funding Provided
by U.S. Environmental Protection Agency and
Iowa Department of Agriculture and Land Stewardship.
Mailing Address: IDALS, Wallace State Office Building, 502 E. 9th Street, Des Moines, IA 50319: PH: 515-281-5321
