MAMMALS OF UTAH 79 



in spatulatus; sides russet; under parts usually heavily col- 

 ored with cinnamon and dark russet or brown hairs ; throat 

 and ventral region lighter ; hips black. Worn pelage : Upper 

 parts dull sooty brown, sides and under parts paler, usually 

 with few rusty overlying hairs. Young: Seal brown, paler 

 beneath. (Hollister.) 



Distribution — Southern British Columbia, Washington, 

 Idaho, and western Montana, south in the mountains to 

 northern New Mexico. Specimens have been taken at Utah 

 Lake, Ogden and Laketown. This species is found quite gen- 

 erally throughout northeastern Utah, being the common 

 muskrat of that vicinity. S. B. Locke reports that muskrats 

 are common in the LaS^l mountains district. 



Habits — Where the brook gurgles softly into the reed- 

 covered pond and surrounding willows protect from intrusion 

 ashore, the muskrat builds its home, depending summer and 

 winter upon the swampy waters for food, protection and 

 shelter. Even the entrance to the den is below the water 

 line, though, shortly, the passage ascends to a snug compart- 

 ment with an air hole leading up through accumulated rushes 

 and twigs. 



Anatomically the muskrat is merely an immense mea- 

 dow mouse with a naked tail flattened on the sides. 



A muskrat usually lives and dies in a single marshy 

 pond unless perchance the water is dried away ; and seldom, 

 indeed, does it go over a hundred yards from its hole. 



More sociable than the rabbit, less so than the beaver, 

 muskrats usually join efforts to build a rat-house or lodge, 

 arid at the approach of danger, the discoverer alarms its 

 companions with a splash of considerable loudness. If imper- 

 iled they frequently join forces, too, in fighting a common 

 enemy. 



About the middle of April the species pair, much loud 

 snarling, squealing, and splashing being heard in the night- 

 time, some of the combatants' tails being either mangled or 

 chewed off. In thirty days from four to nine naked, blind, 

 helpless, young are born, which are suckled until three weeks 

 or a month old. As many as three litters are raised in a 

 year ; and from the manner in which the male assists in nest 

 building the species is thought to be monogamous. 



In July the family begins to build the winter home. 

 Selecting a reed-surrounded strip of shallow water, they drag 

 mud, sticks and vegetation together until the pile is three or 

 four feet high, capped with rushes. As the roof caves in, it 

 is eaten away until finally a self-supporting dome is formed 

 ready to protect the occupants from the chill blasts of winter. 



