Meet The Beavers#
Beaver History#
How long have beavers inhabited North America?#
Beavers controlled the North American landscape well before Europeans colonized New England.
Where did the beavers go?#
Intensive hunting and trapping (between 1600 and 1800), and deforestation for farmland by European colonists eliminated beavers throughout much of North America, including Mass.
When did beavers return to Mass?#
- Beavers were re-established in Berkshire County in the 1930’s, and have since reclaimed most of their former range in our state.
- Beavers returned to the sanctuary in the early 1990’s.
Beaver Identification#
What is a beaver?#
- Beavers are North America’s largest native rodents, weighing between 35 and 80 lbs. as adults.
- Beavers range from two to three feet in length, with an additional ten to eighteen inches for the tail. There is no size difference between adult males and females.
Dinner with a Beaver#
What do beavers eat and who eats beavers?#
- Beavers are strict vegetarians feeding on a variety of aquatic plants and the shoots, twigs, leaves, roots, and bark of woody plants (deciduous trees are preferred to conifers).
- During the winter months branches of trees and shrubs are cached at the bottom of the pond near their lodge. Beavers rely on the cache as their food source when the pond has frozen over.
- Predators vary across a beaver’s North American range. Full grown adult beavers really only have to worry about humans, but coyotes, bobcats, river otters and mink take a share of young beavers. In the right situation fishers and fox shouldn’t be ruled out as potential predators as well.
The Beaver Family#
How big is the family?#
- Beavers are life mates, and will mate between January and March. Females give birth between April and June.
- The couple will have one litter a year usually containing four kits (but may have as many as nine).
- A beaver family unit or colony is typically made up of two adults, the year’s kits, and young from the previous year, or yearlings.
Dam and Lodge#
What is a dam?#
- Dams are structures used to stop the flow of streams and rivers. They are built to form ponds, a habitat beavers need to survive.
- Ponds allow beavers to access food, avoid terrestrial predators, and build lodges.
- The base of a dam is made up of mud, sticks, and stones, then piles of branches, more sticks and mud are added to the base till the flow of water has stopped.
What is a lodge?#
- Lodges are piles of sticks and mud that provide protection from terrestrial predators, and the elements of cold winter months. Lodges can be up to forty feet across at the base and up to six feet high above water.
- An internal chamber, above the water line, is chewed out of the pile of sticks and is lined with dry plant material. A vent leading from the chamber to the top of the lodge allows air to enter.