To a beaver, the slightest trickle of water is the sound of opportunity. It’s said you can give a man a fish and he’ll eat for a day. But, I say, give a beaver the barest of brooks and he’ll create a new world.

I’ve been watching that process of creation ever since last fall, when a family of beavers decided to damn a mere rivulet that slowly drains a 20-acre bog southwest of our house. From there, the water flows about a half mile through a shallow ravine, dominated by alder and young aspen, down into the Lost Lake Swamp. Our two-mile-long snowshoe trail, which I’ve maintained for almost 20 years now, used to cross this little stream. It was just a step over a couple rocks to avoid the water— at least that’s how it was for many years. But last fall, as I was conducting my annual trail maintenance, I found that portion of the trail underwater.

It took a moment of confusion before I deduced the cause, though I still found it difficult to believe, given the miniscule volume of flow. But, yes, in fact, about 100 yards downstream, a family of beavers had built an impressive dam. A trickle through the alder had become a beaver pond.

It’s a process of creative destruction that kills a forest and replaces it with a rich wetland environment that, in its first summer, is already home to at least three broods of mallards and probably more.

It’s a perfect environment for raising young ducks. The pond, which is isolated from any open water source, obviously harbors no giant muskies waiting to inhale a downy little duckling. And the canopy of now-dead alder and aspen offers the young ducks substantial protection from hawks or falcons.

But there was much more at the new pond early one morning this week. Frogs were poking noses from the water, a garter snake was coiled on a sun-splashed rock on the shore, while legions of dragonflies darted around in search of breakfast or a sunny perch of their own.

In the long view, beaver ponds are temporary components on the landscape, even though they can last, at times, for decades. Over time, they change, of course. Our new pond is full of woody cover, but soon enough those dead trees and shrubs will disintegrate and fall below the surface of the dark waters, opening up the pond. The brush will be replaced with true wetland vegetation, like cattails, rushes, or sedges. If they haven’t already, turtles will eventually find their way to this oasis in the forest. I’m curious to watch the transition over the years to come— assuming that the beavers and their progeny continue to maintain the dam.

Beaver ponds are an integral part of the northwoods forest ecology, and as the beaver population has increased, so have the number of ponds. Just scan our area on Google Earth and the telltale signature of the beaver pond can be found in huge numbers.

But their appearance is hardly random. While beavers have adapted to a wide range of land types, and can even be found in corn country, here in the north, beavers feed primarily on the bark of aspen, so they prefer disturbed sites where aspen are regenerating. Our new beaver pond is located on an adjacent state-owned forty that was logged about 20 years ago. In places, it’s grown back heavily to aspen, and that’s particularly true in the area surrounding the beaver pond. The aspen are densely-stocked and all about 4-6 inches in diameter, providing the best possible habitat for an industrious family of beavers.

I like to think of entrepreneurial beavers wandering the woods, looking for the ideal location for a new home, where the aspen is plentiful, and where a trickle of water is calling their name. Then, as with most entrepreneurs, all it takes is hard work to turn their vision into reality.