For the most part, muskrats are herbivores. They consume with relish the leaves, stems and rhizomes of emergent aquatic plants such as cattails, bulrushes, sedges, horsetails, water lilies and arrowheads. Fish, frogs and invertebrates, including crayfish and clams, are also eaten to a lesser extent. Muskrats are voracious eaters (captive muskrats eat 25 – 30% of their weight daily). When their numbers are very high, muskrats can cause what is referred to as an “eat-out,” where they mow down everything in sight.
Like beavers, muskrats can close their upper lips behind their incisors in order to cut plants underwater without taking in water and choking. (photo: two young muskrats feeding on aquatic vegetation)
Over 500 species of sedges in the genus Carex are found in the U.S. – over half of the world’s total. The great majority of these perennial, grass-like plants grow in the moist soil of meadows, marshes and bogs, as well as in high altitudes. Sedges are often distinguished from grasses by their stem, which is typically triangular in cross-section (“sedges have edges”). The flowers of sedges, each surrounded by a bottle-shaped bract, or modified leaf called a perigynium, are clustered on spikelets. The tips of these bracts persist after the seeds have formed, giving the spikelets a prickly appearance.
Because of their wide availability, the seeds are eaten by many kinds of wildlife, especially birds. Wild Turkeys, American Woodcock, Northern Cardinals, Horned Larks, Snow Buntings, Lapland Longspurs, ducks, rails, sparrows, redpolls and finches relish them. In the Northeast, Carex seeds, along with insects, are the most regular items in the diet of Ruffed Grouse chicks. Moose also occasionally feed on sedge seeds. (Photo: Longhair or Bottlebrush Sedge, Carex comosa)
When Black Bears emerge from their dens in the spring, they have lost between 15 and 40 percent of their weight, and food is in short supply. About 85% of a bear’s diet is vegetation, and most trees and shrubs have not leafed out yet. Black Bears often head to wetlands, where grasses and sedges are beginning to sprout. Nutritionally the shoots of these plants provide them with some of the protein they need, but this source of nutrients is short-lived, as the shoots are tender for only a few days before hardening with cellulose. Roots, bulbs, corms and tubers of plants such as Skunk Cabbage and Jack-in-the-Pulpit are sought after, as are the buds of trees, but bears must wait for the bountiful supply of berries and nuts that mature in summer and fall. Those bears living near humans come to rely on foods inadvertently provided by these humans, such as highly nutritional sunflower seeds being fed to birds. One can hardly blame bears for taking advantage of this available source of food during this challenging time. Feeders and cans containing seed should be put in a bear-proof location if you don’t want to encourage “nuisance” bears which, unfortunately, are sometimes killed just for trying not to starve to death.