These aquatic rodents are usually about 2 to 3 feet (nearly 1 m) long, with small eyes, water-repellent brown fur, and a broad, flat tail that enables them to swim gracefully in the water. Although their thick bodies waddle awkwardly on land, beavers are powerful swimmers and can hold their breath for up to 15 minutes. Beavers also possess a set of large, powerful teeth to gnaw away at trees and branches to construct habitats and gather food such as leaves, bark, roots, and aquatic plants.