Muskrats are semi-aquatic rodents found in wetlands across North America, Europe, and Asia. While primarily herbivorous, their diet mainly consists of plants. They also exhibit opportunistic omnivorous behaviors, consuming animal matter when plant resources are scarce or easily accessible. This adaptability allows them to thrive in diverse aquatic environments.
Aquatic and Terrestrial Plant Foods
The majority of a muskrat’s diet, approximately 95%, is composed of various plant materials. They consume a wide array of aquatic vegetation, with cattails being a highly favored food source. Muskrats utilize different parts of these plants, including roots, stems, leaves, and sometimes fruits. They also eat sedges, rushes, water lilies, pondweeds, and bulrushes.
Their consumption of specific plant parts can vary seasonally. For instance, they may preferentially select the core of cattails, which contains lower amounts of lignin and more moderate levels of cellulose, making it easier to digest. When aquatic plants are less abundant, muskrats may also forage on terrestrial plants found near water bodies, such as grasses, clover, and agricultural crops like corn, soybeans, wheat, and rice.
Animal-Based Dietary Components
Animal-based components typically make up about 5% of a muskrat’s diet, especially when plant food is limited. Specific examples of animal prey include freshwater mussels and clams, often consumed at designated feeding stations, leaving behind piles of shells. Muskrats also prey on crayfish, small fish, frogs, and small turtles. Insects, such as aquatic insects and beetles, are part of their occasional diet. In some instances, they may consume carrion, particularly dead fish exposed during spring thaws.
Foraging Behaviors and Food Storage
Muskrats employ several distinct behaviors to obtain and manage their food. They use their sharp incisors and forefeet to cut and harvest plants, often dragging them to a safe location for consumption. These locations often include feeding platforms, structures built in the water from cut vegetation, or on logs and rocks, providing protection from predators while they eat.
During colder months, muskrats create “push-ups” or feeding huts. These are small, dome-shaped structures made of vegetation and mud, built on ice or within their lodges and burrows. Push-ups serve as insulated resting and eating spots, allowing muskrats to access food under the ice and breathe. While beavers typically store large quantities of food for winter, muskrats do not accumulate extensive food caches. Instead, they forage for fresh plants daily, sometimes even consuming the inner walls of their lodges or burrows if food becomes extremely scarce. Muskrats are generally most active at night or during dawn and dusk, though they can forage at any time.