Forest Preserve District of Cook County, Illinois
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Tough Times for the Muskrats
Nature Bulletin No. 3  February 24, 1945
Forest Preserve District of Cook County
Clayton F Smith, President
Roberts Mann, Superintendent of Conservation


This has been a sorry year for the muskrats. The long drought, last summer and fall, dried up many of the smaller marshes and ponds where they had been living and forced them to migrate overland to new homes. Many undoubtedly were killed while enroute by mink, hawks, or dogs. Even the larger marshes and ponds were made smaller and more shallow by the drought and now this severe winter, with its long, bitter cold, has caused many of them to freeze solid to the very bottom; thus sealing the muskrats up in their lodges and preventing them from swimming around under the ice to get food.

When this happens, and the food stored in the "house" is finally gone then the muskrats often turn cannibal and eat the younger or weaker ones. You some times see a muskrat with its tail chewed off. Finally they have to eat a hole out through the lodge and go out across the ice and snow in search of food. Then they are easy prey for mink, owls and hawks. And then the hole leaves easy access for a prowling mink to enter and kill all those inside.

The Forest Preserve District, during the past 12 years, has created or restored more than 50 marshes and ponds particularly in the Palos section. One of the largest of these is Tuma Slough on both sides of Willow Springs Road (104th Ave. ), just south of 95th St. containing 30 acres of water area. Here may be counted 68 muskrat houses along the shore or projecting above the ice farther out. About half of them are large ones. These houses -- or lodges -- are constructed of cattails, bulrushes, flags, marsh smartweed, coontail, and other aquatic plants. They are circular mounds rounded on top, from four to six or more feet in diameter at the base, and project from two to four feet above the water. Each pair of muskrats constructs such a house during the late summer and fall, adding to it each day until winter comes, with a system of underwater tunnels to reach it, and chambers above the water-line for storage of food and for living room.

Muskrats are very prolific. The first litter will be born in March, the second in June, the third in August and sometimes a fourth in October. There are usually from 5 to 3 "kits" in each litter. Thus each pair may produce from 15 to 30 young each year. That is why, of all fur animals trapped in the United States each year, the total money value of the muskrat fur sold is greatest.

Incidentally, muskrats are mighty good to eat. They live largely on the fleshy roots, tubers, stalks and other parts of the vegetation that grows in the water or on land near their homes. they also eat mussels, frogs, crayfish, some insects and occasionally a little duckling or other bird. But people are prejudice against them because of that long hairless, rat-like tail and the "rat" part of the name. So, when served in restaurants, they are re-named "marsh rabbit".

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