The beaver, fairly common throughout Kentucky, is North America's and Kentucky's largest rodent. Adult beavers weigh between 35 and 60 pounds, with some reaching weights of 70 to 80 pounds. Adult beavers range in size from 25 to 31 inches from the tip of their nose to the base of their paddle-shaped tail.

Beavers typically have large heads, indistinct necks, thick, stout bodies and small ears and eyes. Perhaps their most recognized feature is a large, flat, hairless tail shaped like a paddle. This six- to eight-inch wide and 10- to 12-inch long tail is used for support when the beaver is on land and as a steering, swimming and communication device when it is in the water.

Like many other rodent species, beavers have a pair of continually growing, large, orange front teeth (incisors). The beaver must keep the incisors worn back by using them daily. Color can vary from blond to almost pure black. It is almost impossible to tell the difference between male and female beavers unless the female is lactating and has swollen mammary glands.