Recently I was both delighted and dismayed to discover the handiwork of a beaver in a nearby wooded wetland, where the furry little engineers had constructed a barrier of aspen and birch branches and mud across a narrow culvert, damming the small stream and creating a lovely wetland in its place. It was beautiful and serene, as titmice and cedar waxwings flitted and twittered all around, and the autumn reflections of overhanging red maple, yellow birch, black cherry and hemlock danced in gentle ripples upon the surface of the newly-formed pond. On the one hand, I celebrated the creation of this new wetland as a gift of nature — wetlands provide critical habitat for fish, ducks, geese, turtles, amphibians, mink, deer and countless other creatures, while regulating and recharging ground water supplies, reducing erosion, filtering out sediments, detoxifying pollutants, and minimizing flooding downstream. And I celebrated the creativity, ingenuity, and adaptability of the beavers themselves, whose architectural, engineering, and construction skills are nothing short of phenomenal. On the other hand, I also grieved, knowing that these particular beaver (probably a young, newly-mated pair) were likely doomed, for their wetland was in the midst of property where their activity would not be tolerated by the landowners, and where human concerns over the loss of trees and flooding elsewhere would take precedence over the ways of nature. No other mammal has a greater ability to alter its environment than the beaver, except for humans. And rarely will humans tolerate the competition.

The North American beaver (Castor canadensis) is the largest member of the order Rodentia, named from the Latin “rodere,” which means “to gnaw.” Their scientific name refers to the beaver’s castor glands, which produce a special scent with which they demarcate their territory. And masters at gnawing they are! With chisel-like incisors and powerful jaws, beaver can easily cut down a five-inch thick willow in less than three minutes, merely by biting out chips in a deep groove around the trunk. Beaver especially seek out trees such as aspen, poplar, willow, birch, and maple, using them as preferred foods and to provide construction materials with which they create their dome-like home (the lodge) and their quiet-water habitat (via their dam). Once a tree is felled, beaver trim and cut the branches into pieces, and carry them to the lodge or dam site. Larger branches provide the dam’s scaffolding, which is reinforced and packed with smaller twigs, grasses, cattails, and other plant material (even corn stalks!), then caulked with mud. Dams may be six feet high or more, reaching twenty-five to forty feet across. Their purpose is to create a still, safe, and relatively deep watery habitat in which the lodge may be built, winter food may be stored, and young may be raised.

A pair of beaver typically mate for life, breed between December and February, and bear four to five young about four months later. While newborns can swim within a half-hour after birth, mama beaver keeps them close and may carry them on her back as she swims.  Although parents produce a new litter each spring, juveniles from the previous year remain with the family a second year, helping with housekeeping and the care of younger siblings. Most beaver colonies are thus families of four to eight individuals, the two adults and their children from the previous two breeding seasons. Family members greet each other, groom each other, wrestle, dance, and play — along with caring for and maintaining their carefully constructed habitat. Most of these activities are rarely seen, however, because beaver are nocturnal and busiest at night. Upon reaching sexual maturity at twenty-one months of age, the young adults are sent away to disperse into new territories, build new dams and lodges, and begin their own little families.

Lodges, like dams, are impressive. Most lodges consist of one or more compartments, each with two underwater openings for exit and entry (especially important for escaping from predators such as dogs, coyotes, or bear). Living quarters for the family are in a hollow near the top of the lodge, with wood chips on the floor to absorb moisture and a vent to admit fresh air. A cache of winter food is stockpiled nearby, usually as cut branches poked into the muddy pond bottom and ready for the taking. When eaten, a branch is held like an ear of corn, and the outer cork, cambium, and sweet inner bark are eagerly consumed, along with leaves, fruits, seeds, and even roots.

As remarkable as they are, beaver were once valued only for their dense, insulating pelts, and relentless and uncontrolled exploitation nearly led to their disappearance. Fortunately, by the 1940’s, beaver began re-occupying New York State, and new appreciation of their ecological role and revised management strategies led to their spectacular recovery. With recovery have come renewed beaver-human conflicts — and rarely do the beaver win. It doesn’t have to be this way. If progressive thinking, human tolerance, and innovative solutions are embraced, solutions can be found. We humans need to try harder. Wherever possible, let’s leave a place for wildlife, and experience a richer, more diverse, and more wondrous world, even in our own backyards!

Becky Nystrom is a Professor of Biology at Jamestown Community College, a long-time CWC supporter and volunteer and a founding trustee of the CWC. The Chautauqua Watershed Conservancy is a local not-for-profit organization that is dedicated to preserving and enhancing the water quality, scenic beauty and ecological health of the lakes, streams, wetlands and watersheds of the Chautauqua region.  For more information, call 664-2166 or visit www.chautauquawatershed.org or www.facebook.com/chautauquawatershed.