How Beavers, Rewilding Allies, Transform the Landscape

← Back to Featured News

Several years ago, I moved into a cabin in a cold mountain hollow adjacent to NEWT’s Woodbury Mountain Wilderness Preserve. At the time, an alder swamp fed by the headwaters of Pekin Brook filled the bottom of the valley. According to the previous landowners, there had been a beaver pond there until floodwaters from Hurricane Irene breached the dam in 2011, draining the pond within minutes. With the area’s hardwood supply depleted, preventing the resident beavers from rebuilding the destroyed dam, they apparently chose to relocate. Over the 13 years since the beavers left, the pond transitioned first to a wet meadow, and then eventually to an impenetrable alder swamp.

According to Tom Wessells’ Reading the Forested Landscape, beavers will almost always return to the site of a previous pond, though they will usually wait until the woody vegetation reaches at least “pole size.” Since beavers receive most of their nutrition from cambium – the outermost layers of a tree – a decade-old alder swamp provides them with an abundant source of stems that are relatively easy to fell and transport, as well as plenty of cambium-filled surface area for them to chew on.

These factors in mind, I knew that it was only a matter of time before the beavers would be back. Sure enough, during the spring of 2024 I started noticing the telltale signs that they had returned. First, piles of mud started to appear along the banks of the brook – an advertisement that they are actively courting a mate and looking to build a lodge. Then, I started noticing occasional beaver chew on willows, alders, and birches; they were sampling the local cuisine. Finally, in early May a small heap of alder branches and mud began to pile up across the brook, and a puddle formed: dam construction had begun.

I decided to put up a wildlife camera to document the process. Over several weeks, I captured some incredible moments in the landscape’s transformation. Beavers do most of their work at night, so every morning the dam was noticeably taller and the puddle deeper. Within days, the latter was a knee-deep pond attracting Wood Ducks and Great Blue Herons; within weeks, the beavers had removed enough alders that I could put in a canoe and paddle around. The chorus of spring peepers eventually gave way to the croaks of bullfrogs, dragonflies filled the evening sky, and brook trout darted beneath my boat. The dam itself became a hotspot for wildlife, with raccoons, black bears, and flying squirrels all visiting to investigate the new landscape feature.

With the arrival of summer, beaver kits – born sometime between mid-may and early June – began to venture out of the water with their parents to explore the dam. Unlike most other rodents, young beavers stay with their parents for two years to learn the many skills required to construct and maintain dams, lodges, and associated waterways. The young beavers seen here may only be a week or two old, and they are following in their parents’ footsteps as they watch the construction of the dam.

I removed the camera in early July when heavy rainfall threatened extreme flooding, fearing that the half-constructed dam would not hold up. However, to my surprise the dam withstood several fierce storms. After the storms, the beavers embarked on repairs and additional construction. They worked nightly on the dam until late August, when the pond reached its greatest extent and the furry engineers turned their efforts to building their lodge on a nearby bank. As fall approached and the nights grew longer, the family began collecting their winter food cache of willows, alders, and birch. Near-constant sounds of chewing echoed through the hollow from sunset to sunrise until the pond iced over.

It’s one thing to read about the myriad benefits of beavers as keystone species and ecosystem engineers, but it’s another altogether to watch the process unfold in real time. I am struck by the structural and biological diversity these creatures bring to the landscape as allies in the rewilding process, and I hope to continue sharing snippets of their journey.

Photography by Jerry Monkman and Jason Mazurowski.