Beavers

Beavers are large, semiaquatic rodents native to North America and Eurasia. They belong to the family Castoridae and include two extant species: the North American beaver (Castor canadensis) and the Eurasian beaver (Castor fiber). Adults typically measure 60 to 90 cm in body length, with tails adding another 25 to 50 cm; they can weigh 11 to 32 kg. They have dense fur, strong incisors that grow continuously, and webbed hind feet. The broad, flat tail functions as a paddle for swimming and as a fat storage when food is scarce.

Beavers are primarily herbivores, feeding on bark, cambium, leaves, roots, and aquatic plants. They harvest trees such as aspen, willow, and birch, gnawing with their orange incisors to fell trunks for dam-building and food stores. They are crepuscular or nocturnal and live in family groups that usually include a pair and their offspring.

Their most notable behavior is dam construction. Beavers build dams from sticks, mud, and stones to create ponds that provide protection from predators and access to food during winter. Lodges built of sticks and mud offer shelter and underwater entrances. These activities significantly alter hydrology and create wetlands that support diverse plant and animal life, making beavers a keystone species in many ecosystems.

Beavers inhabit streams, rivers, lakes, and wetlands across their ranges; they prefer slow-moving water with abundant woody vegetation. Reproduction typically occurs once a year, with a gestation around 107 days and litters of 1–6 kits. Conservation status is generally favorable, though local populations have declined due to habitat loss and trapping in some regions.