Pygmy Shrew (Sorex hoyi) in Montana East of the Rocky Mountains with Comments on its Distribution across the Northern Great Plains

摘要

Range maps for Pygmy Shrew (Sorex hoyi) show a large hiatus over much of the northern Great Plains between the Rocky Mountains and easternNorth Dakota. We report a new record of the Pygmy Shrew in northeastern Montana, review previous records for the state and adjacent regions bordering Montana to the north and east, and suggest that the range boundary in the northern Great Plains be redrawn farther south to include all of Montana north of the Missouri River. This is consistent with the known range of the Pygmy Shrew in eastern North Dakota and South Dakota, where the species has been documented only north and east of the Missouri River, although records are still lacking from north of the Missouri River in northwestern North Dakota and adjacent regions of Canada. Pygmy Shrews will probably be found at additional localities in prairie regions of Canada adjacent to Montana, most likely in association with prairie pothole wetlands, river bottom riparian vegetation, and hardwood draws.