A muskrat is a rodent about the size of a small cat that lives in and around rivers, lakes, marshes, and wetlands across North America. Despite its name, it's not a rat and it doesn't smell like musk (though it does have scent glands). Muskrats are excellent swimmers with webbed back feet and a long, flat tail they use like a rudder to steer through water.

These industrious animals build dome-shaped lodges out of mud and cattails in shallow water, similar to beaver lodges but smaller. They're mostly vegetarian, munching on cattails, water lilies, and other aquatic plants, though they'll occasionally eat shellfish or small fish. You might spot a muskrat's V-shaped wake as it swims across a pond at dawn or dusk.

Muskrats played an important role in American history: their thick, waterproof fur made them valuable in the fur trade, and trappers pursued them extensively in the 1800s and early 1900s. Today they're still common in wetlands, where they help maintain healthy ecosystems by eating plants and creating channels through marshy areas. While they look somewhat like small beavers, muskrats are much smaller and their tails are skinny and scaly rather than broad and paddle-shaped.