Best Friends in Nature: Heron & Beaver Edition

Heron & Beaver

Heron & Beaver, photo by Corinne Schwarz

Here’s a cool photo from May of 20111 that I never featured for some reason. That reason might have been so I could link to this article from the Birdwatchers General Store in Cape Cod about the symbiotic relationship between beavers & blue herons. It says in part:

It is thought that the Bay State’s famed naturalist, Henry David Thoreau, never saw a Great Blue Heron nest in Massachusetts. Why? It’s partly because there were no beavers living in MA during Hank’s lifetime. Way back in the 1700s, unregulated cutting eliminated the trees beavers needed for survival.

…Today, beavers are once again thriving in MA. That’s not only great news for anyone who enjoys seeing beavers, but it’s great news for Great Blue Herons as well.

I think we all know how beavers operate. They find a secluded stream, cut down a few trees and dam it up. The area behind the dam becomes flooded and turns into a beaver pond. Why do beavers need to go through all the work to build their very own pond? The beavers create a pond so they can have underwater access to their lodge, even when everything is frozen in the winter. However, the newly built pond often entraps large trees, which eventually drown and die. Dead trees growing out of the center of a pond may look eerie to us, but they are magnets to herons. The dead trees provide excellent platforms for the birds to build their nests on. In addition, the water prevents terrestrial predators from munching on the eggs and babies. Between the swampy setting, the dead trees, the bulky stick nests and the gangly herons, the whole scene looks a Gothic nursery, but the birds love it.

Read on for lots more, and for more about these two species, see Know Your Michigan Birds: Great Blue Heron and Castor canadensis, the American beaver on Michigan in Pictures.

View Corrine’s photo background bigtacular and see more in her Water Wheel slideshow.

More spring wallpaper and more “Best Friends in Nature” on Michigan in Pictures.

Castor canadensis, the American beaver

Floating Beaver

Floating Beaver, photo by Kevin Povenz

Castor canadensis (American beaver) from the University of Michigan Animal Diversity Web explains:

Beavers are primarily aquatic animals, and the largest rodents in North America. They have a waterproof, rich, glossy, reddish brown or blackish brown coat. The underhairs are much finer than the outer, protective, guard-hairs. The ears are short, round, and dark brown in coloration. A beaver’s hind legs are longer than its front legs, thus making the rear end to be higher than the front end while walking.

Some facts:

  • Beavers eat bark and cambium (the softer growing tissue under the bark of trees). Their favorites include willow, maple, poplar, beech, birch, alder, and aspen trees. They also eat water vegetation, as well as buds, and roots. Cellulose, which usually can not be digested by mammals, is a major component of their diet. Beavers have microorganisms in their cecum (a sac between the large and small intestine) that digest this material.
  • Under favorable conditions, beavers will produce their first litters at two or three years of age. The average lifespan of a beaver in the wild is 10 to 20 years.
  • Beavers usually live in family groups of up to 8 related individuals called colonies. The younger siblings stay with their parents for up to 2 years, helping with infant care, food collection, and dam building. Beaver families are territorial and defend against other families.
  • Beavers build dams to slow down the flow of water in streams and rivers and then build stable lodges for shelter. The dams are engineered according to the speed of the water; in slow water the dam is built straight, but in fast water the dam is built with a curve in it.
  • Beavers maintain wetlands that can slow the flow of floodwaters. They prevent erosion, and they raise the water table, which acts as a purifying system for the water. This happens because silt occurs upstream from dams, and toxins are then broken down. As ponds grow from water backed up by the damn, pond weeds and lilies take over. After beavers leave their homes, the dams decay, and meadows appears.

Head over to ADW for more information including some photos.

Check this photo out on black, see it bigger in his Animals slideshow and also view more great shots from Kevin on Michigan in Pictures.

More Michigan animals on Michigan in Pictures.