North American Beaver
The North American beaver is one of two extant beaver species. It is native to North America.
This beaver is the largest rodent in North America. Adults usually weigh from 11 to 32 kg, with 20 kg being typical. The head-and-body length of adult North American beavers is 74–90 cm, with the tail adding a further 20–35 cm. Very old individuals can exceptionally exceed normal sizes, weighing more than 40 kg or even as much as 50 kg.
Like the capybara, the beaver is semi-aquatic. The beaver has many traits suited to this lifestyle. It has a large, flat, paddle-shaped tail and large, webbed hind feet. The unwebbed front paws are smaller, with claws. The eyes are covered by a nictitating membrane which allows the beaver to see under water. The nostrils and ears are sealed while submerged. A thick layer of fat under skin insulates the beaver from its coldwater environment.