Moose, You Otter Have Beavers Nearby

Once again, scientists conclude that beavers do a lot of good for other animals and plants.

Beavers engineer their ecosystems in a way that helps moose and otters (New Scientist). When naturalists re-introduced beavers into parts of Finland, they noticed “increased activity of several species, including moose, otters, and weasels.”

Beavers change the environments they occupy in several ways. Their dams flood large areas, creating shallow ponds that harbour lots of invertebrates. The trees they fell create open spaces in the forest where young saplings can grow. When beavers leave a pond and their dams break, the previously flooded area is rich in nutrients and can become a meadow.

Felled trees, saplings and aquatic plants can all provide food for moose. Weasels and pine martens feed on smaller mammals, which may benefit from dead trees they can shelter under. Red foxes and raccoon dogs eat frogs, which are plentiful in beaver ponds. Besides feasting on frogs and fish in the ponds, otters make use of abandoned beaver lodges and ice holes during the winter.

Bats and waterbirds also join the fun. Beavers, the “ecosystem engineers” behind all this rich ecology, make it happen because of their well-designed teeth, nose flaps for swimming, webbed feet and tails. An old IMAX film, Beavers, showed what happened when a beaver family moved into a Montana community and created a huge lake with their dam.

One beaver dam can impound a lot of water. Photo by David Coppedge, Lundy Canyon.

The well-made IMAX film is worth watching if you can locate it. You’ll fall in love with the adorable beaver family, as you marvel at how they transform the landscape. Here’s the trailer.