The muskrat (Ondatra zibethicus) is a semi-aquatic rodent native to North America and introduced in parts of Eurasia. These medium-sized mammals are recognized by their dense, dark brown fur, slightly webbed hind feet, and a long, vertically flattened, scaly tail used for propulsion. Muskrats inhabit various freshwater environments, including marshes, ponds, lakes, and slow-moving streams with abundant emergent vegetation. They construct dome-shaped lodges from plant material or burrow into banks to create sheltered dens.
Are Frogs Part of the Muskrat Diet?
Muskrats are omnivores and will consume frogs when the opportunity arises. While the vast majority of their caloric intake comes from vegetation, they are known to prey on small amphibians, including frogs. This consumption is supplemental and minor in the context of their overall food requirements. Frogs are not a primary food source, but rather a protein-rich addition to their diet.
This carnivorous tendency is often directed toward smaller, slower-moving, or injured individuals that are easily captured in the water or near the shoreline. The presence of frogs in the diet is highly dependent on local availability and environmental conditions. While muskrats do eat frogs, it represents a small fraction of their total food consumption throughout the year.
Primary Diet Staples: Aquatic Vegetation
The muskrat’s diet is primarily rooted in aquatic botany, with plant material making up 90% or more of their consumed biomass. Their digestive system is specifically adapted to process the cellulose found in wetland flora. They rely heavily on the roots, stems, and leaves of emergent aquatic plants that grow in their habitat.
Preferred food items include the roots and stems of cattails, bulrushes, sedges, and water lilies. Muskrats use their large, prominent incisors to cut and harvest this tough vegetation, often while submerged. They frequently create feeding platforms or “push-ups”—piles of vegetation and mud—where they can consume their food safely out of the water. This continuous foraging activity on the root systems can sometimes lead to localized areas of denuded marsh known as “eat-outs.”
Opportunistic Consumption of Animal Matter
The non-vegetative portion of the muskrat’s diet is what characterizes them as opportunistic omnivores. This animal matter consumption typically constitutes only about 5% to 7% of their total food intake. This small percentage of animal protein becomes more significant when their preferred plant food becomes scarce or inaccessible.
This foraging behavior is often heightened during the cold winter months or periods of drought when vegetation is less abundant or locked beneath ice. When plant resources dwindle, muskrats actively seek out other aquatic life. Examples of animal matter they consume include freshwater mussels, crayfish, snails, and small, slow-moving fish. They will also consume carrion, such as dead fish or turtles, that they encounter in their aquatic environment. The inclusion of frogs is part of this broader, flexible, and opportunistic feeding strategy, allowing the muskrat to adapt to seasonal fluctuations in food availability.