Baby beavers, known as kits, enter the world developed, with fur, open eyes, and the ability to swim shortly after birth. Despite this early readiness, their initial survival hinges on their mother’s care and a specialized diet that evolves as they grow. This transition from dependence to self-sufficiency involves distinct dietary phases that prepare them for an adult beaver’s plant-based lifestyle.
First Foods of Kits
For their first several weeks, beaver kits rely exclusively on their mother’s milk. This milk provides all necessary nutrients for their rapid growth and development. This nursing phase typically lasts for about six to eight weeks, during which they remain in the lodge. The mother’s milk also supplies antibodies, which are important for building the kits’ immune systems.
Gradual Shift to Plant-Based Diet
Around three to four weeks of age, beaver kits begin a gradual transition from milk to solid foods. They begin incorporating tender plant materials like soft leaves, shoots, and aquatic vegetation. As they mature, their digestive systems adapt to process cellulose, a complex carbohydrate abundant in plant cell walls. Beavers possess unique gut microorganisms that help break down cellulose, enabling them to digest a significant portion of it.
Their diet continues to diversify, eventually mirroring that of adult beavers. Seasonal availability influences what they eat; in spring and summer, soft flora like grasses, water lilies, and sedges are common, while in autumn and winter, they shift towards woody plants. This includes the inner bark, or cambium layer, from trees like willow, aspen, and cottonwood. Beavers do not eat the wood itself, but rather the cellulose found beneath the bark.
Learning to Forage
Young beavers learn foraging skills from their parents and older siblings. Kits observe and mimic adults, learning to identify edible plants and gnaw on woody vegetation. This hands-on learning is important for their independence. Young beavers stay with their family group for about two years, allowing them to master these survival skills.
Parents teach them what to eat and how to gather food, including clipping branches from felled trees. This guidance extends to food caching, where beavers store branches and woody materials underwater near their lodge for winter consumption. This collective effort ensures a reliable food supply when external foraging is limited by ice. Through this learning, kits gradually become adept at finding and processing their own food, preparing them for independent life.