Mice, Voles & Rats
New World Mice & Rats (Cricetidae)
Measurement: Size: 57 cm Weight: 1 kg (2.2 lbs.)
Description: Often mistaken for a beaver when seen swimming in montane marshes or rivers, the muskrat has much in common with its tennis-racket tailed relative. It is a very large rodent with dark coat, and a long tail. The tail is flattened left to right, allowing it to add to the muskrats swimming ability. They move their tail from left to right to propel them through the water, and the tail is visible in the wake behind the muskrat. This can be helpful in distinguishing muskrat from beavers. They spend most of their time in the water, building small beaver-style lodges or excavating bank burrows. They build their dens just before winter, in water too deep to freeze. Although they build lodges, they don't build dams. They often build mini-structures in radiating patterns away from the lodge. Large enough for a single individual, they are used as breathing holes to allow a wider winter foraging range. They feed on cattails, bulrushes, sedges, insects, carrion, frogs and fish. Extremely strong swimmers, they can stay underwater for as long as 15 minutes with 3 or 4 minutes the average. Like most rodents, they are very productive, usually producing at least two litters of up to eight young per year. Although born blind and toothless, they are sent to fend on their own after only about four weeks.