Thursday Thirteen 29: Beaver Ecology

There are many smallish bodies of water near our home, and many of them are homes of beavers. Often when I walk at dusk, a beaver will slap his tail on the water and swim off, bringing me out of my reverie and happily aware that our landscape is full of life.

Beavers are among my favorite animals. Though their taking down of trees and building of dams seem destructive, beavers are actually very creative engineers adept at modifying the landscape to suit their needs. They create win-win situations for everybody because they provide habitat for a variety of plants and animals. When I think of the benefits beavers bring to an area, I am awestruck by what these little guys can do with a few teeth and strong jaws.

1. Beavers dam rivers and streams to form ponds.

2. The base of a dam is made of stones and mud. Beavers place sticks on top of this foundation. Beavers scoop the mud with their forepaws and pat it down with their feet and snouts.

3. Beaver ponds provide habitat for beavers' food of choice: water lilies, cottonwood, willow, and alder.

4. Since beavers' predators live on land, the water also provides a security perimeter.

5. Trees whose habitat has been flooded die; others are felled by beavers.

6. Dragonflies, butterflies and fruit flies also thrive.

7. Animals such as rabbits, salamanders, and water foul that are on the move from the human-disturbed ecosystem who are looking for food and desirable habitat find sanctuary near beaver ponds.

8. Various waterfowl, especially migrating ducks, will use the beaver pond as a staging area on their fall and spring migration, landing to eat the water plants and insects that were bubbling up in the water.

9. Many animals significantly supported by the work of beavers were driven to local extinction in the nineteenth century, around the same time we trapped out the beavers.

10. The pond itself becomes a liquid cafeteria. Bacteria breaking down the drowned vegetation are eaten by protozoa, the food for creatures like cyclops, daphnia, fresh-water shrimp, mosquitoes (of course), dragonflies, caddis worms, tadpoles, water spiders and so on.

11. Painted turtles, owls, herons, kingfishers also thrive in this habitat. They thrive on the flies and frogs that are in ample supply here.

12. Once the food supplies run out for beavers, they move on. The pond will eventually dry into a fertile meadow.

13. That meadow will sustain flowering plants, trees.....and perhaps, some day, another beaver pond...

Find more on beavers here.

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