By Michael Callahan
When Massachusetts citizens voted overwhelmingly in 1996 to outlaw steel jaw leghold traps, other body-gripping traps, and snares for capturing fur-bearing animals, critics of the law loudly proclaimed that disaster was imminent. Many claimed that the trapping restrictions would cause the state to be awash in beavers and flood waters because they mistakenly felt that trapping was the only effective beaver management tool.
Human/beaver conflicts occur across North America. To understand why, it is important to have an historical perspective. The North American beaver, Castor canadensis, has existed for millennia. Native Americans referred to beavers as "Little People" because beavers are second only to humans in their ability to modify their environment to suit their own needs. Beavers were revered by Native Americans who understood that beaver dams and the ponds they created support a vast array of wildlife.
Modern biologists understand their value, too. They now classify the beaver as a "keystone" species - one whose presence within an ecosystem supports a host of other species and is critical for maintaining biodiversity. Beaver damming activity also has many other important environmental benefits, including improving water quality and controlling floods. As European settlements spread from coast to coast, trappers typically blazed the trail - leading explorations in search of the extremely valuable beaver pelts. While early settlers may have understood the value of pelts, they failed to understand the value of beaver-created wetlands. As a result, wetlands were drained and unregulated beaver trapping nearly led to the extinction of the North American beaver.
As our country grew, extensive human development occurred in the absence of beavers. Beaver wetlands, once drained, became farmland; houses, roads, railroads, and other development were often built in or near the low-lying areas that beavers once inhabited.
The 20th century brought increased awareness of the value of beavers and wetlands, as well as land use changes as some farms reverted to forested areas. Beavers were reintroduced into many states, including Massachusetts, and spread to areas where beavers had not been seen for hundreds of years. With improved regulations and management, and because the commercial value of their pelts had dropped, they thrived. Occasionally however, conflicts would arise as beavers built dams and flooded developed areas.
Typically, when dam building by beavers created flooding issues for humans, the beavers were trapped and killed and the dams destroyed. In fact, for many decades beaver trapping and dam breaching were the only management methods used to handle beaver-related flooding issues.
In the 1990s, successful alternatives to destroying beavers and their dams were developed. These innovative technologies, called flow devices, created the opportunity for humans and beavers to peacefully coexist. Flow devices (also called water control devices, Beaver Deceivers™, beaver bafflers, etc.) are typically either specially designed pipes installed through beaver dams to control pond levels, or specially designed fencing to prevent beavers from damming road culverts. Flow device pioneers included Michel LeClair in Ottawa and Skip Lisle in Maine, as well as scientists at South Carolina’s Clemson University.
In Massachusetts, after voters restricted trapping in 1996, there was a critical need for alternatives. Only a handful of effective flow devices existed in the state. Meanwhile, local newspapers reported on the issue in a way that frequently fanned the flames of animosity toward beavers. Problems were dramatized, while solutions rarely received the same attention.
Fortunately, the flow device pioneers freely shared their knowledge and experience. Thanks to them, my wife and I were able to start a volunteer group called the Pioneer Valley Wetland Volunteers (PVWV) and, in 1998, we began installing flow devices at beaver conflict sites. Despite no formal training or experience, our volunteer efforts were largely successful and demand for our group’s services grew. By the end of 1999, our flow devices had resolved 70 different beaver problems in Massachusetts - without harming the beavers.
To date, Beaver Solutions™, a company I started in 2000 after PVWV disbanded, has resolved over 800 beaver conflicts with flow devices. While new problems still occur, beaver conflicts are now rarely headline news in Massachusetts. Over time, it has been shown that flow devices are usually the most cost effective, long-term, humane, and environmentally friendly tool to resolve human/beaver conflicts. In fact, in my experience, flow devices are the best management tool for approximately three out of every four human/beaver conflicts.
Installing flow devices is extremely gratifying work. We are able to solve very real problems for people, while at the same time allowing beavers to remain on the landscape. Finding this middle ground of coexistence has immense benefits for humans, beavers, a myriad of other species, and the health of our planet.
To facilitate the spread of this technology in other parts of this country, we recently completed an instructional video that teaches people how to build and install successful flow devices. This groundbreaking DVD would not have been possible without a very generous grant from the Animal Welfare Institute, as well as the assistance and cooperation of many people and organizations - in particular, Rikk Desgres of Pinehurst Studios, Heidi Perryman of Worth A Dam, Laura Simon of HSUS, and my wife, Ruth Callahan.
The return of beavers across North America is cause for great celebration. While the ponds that beavers create can sometimes cause problems for humans, nonlethal solutions are readily available. Sharing the landscape with beavers benefits us all.
Michael Callahan is President of Beaver Solutions, a company that specializes in humanely resolving human/beaver conflicts.