Northern Prairie Wildlife Research Center
Official Publication of the
State Game and Fish Department
100 North Bismarck Expressway
Bismarck, North Dakota 58501-5095
Grondahl, Chris. 1999. A Closer Look: The Yellow-Rumped Warbler. North Dakota Outdoors 61(10):15.This resource should be cited as:
Grondahl, Chris. 1999. A Closer Look: The Yellow-Rumped Warbler. North Dakota Outdoors 61(10):15. Jamestown, ND: Northern Prairie Wildlife Research Center Online. http://www.npwrc.usgs.gov/resource/wildlife/closlook/yellwarb.htm (Version 02NOV99).
Yellow-rumped is the name given a warbler once known as two separate species. In 1973, the Ornithologists' Union decided birds previously known as Myrtle's and Audubon warblers were actually geographic representatives of one species, not two. They were considered separate species because one population was found in the western United States and the other throughout central Canada and portions of the northern United States. Bird relationships and incidences of crossbreeding helped experts classify them as one.
The yellow-rumped warbler is only a migrant through North Dakota. It breeds throughout Alaska, the Canadian provinces and western United States.
Yellow-rumped warblers construct bulky nests of twigs, grass, and bark fibers, lined with feathers, in coniferous trees 10-20 feet off the ground. Wintering grounds include thin strips along the East and West coasts, the southern United States and Mexico. It winters farther north than any other warbler species.
Yellow-rumped warblers show up in North Dakota between mid-April and early May. They are abundant and often found in shelterbelts and other open, wooded areas. Birds remain in the state for a few weeks, but are normally gone by the end of May.
Although they primarily eat insects, they can survive on various berries for extended periods. They are about the same size as other warblers, about five inches long.
The yellow-rumped breeding male plumage is bright and easy to distinguish from other warblers. They often have yellow patches on their sides that are not found in other warblers. They have a bluish-gray back with black streaks, yellow crown, white underparts and a white eye ring.
Females are similar to the male but have a brown back and are more dull in appearance. As with other birds, young are difficult to identify.
The best way to locate yellow-rumped warblers is to look for a wooded patch in late April, through which you can slowly creep, searching the branches with a good set of binoculars. You may be amazed at what materializes.