There were a host of beaver articles in the past few days that deserved mention. I would call these The Good, The Bad and The Ugly but they are more like the Excellent, the Inspiring and the Whiney, which is not as catchy a title. For an excellent read I would check out Mary F. Wilson’s “Beavers in Winter” article, where she describes how our favorite species gets by in Juneau, Alaska. If her name sounds familiar, it should because she’s the co-author of the Beavers of Mendenhall Glaciar Book with our good friend Bob Armstrong.
Beavers seldom venture into the open air outside the lodge in winter, when ice covers their ponds, so for months a family of beavers breathes “indoor” air, using oxygen and generating carbon dioxide. Beaver lodges have underwater entrances, and mud seals the walls, so air exchange is effected through a ventilation hole in the roof. Apparently this roof vent is sufficient to keep carbon dioxide from building up and allow an influx of oxygen, because when researchers measured the levels of those gases inside an occupied lodge, they stayed nearly constant.
Temperatures inside a well-built lodge also do not vary much. For example, when outside temperatures drop to minus 20 degrees Celsius (about minus 4 degrees Fahrenheit), inside temperatures remain just above freezing. Thick walls obviously conserve more body heat than thin walls, so inside temperature varies more if the walls are thin.
Go read the whole thing and think about the adaptive skills of an animal that can survive at those temperatures and equally well in a bank hole on Alhambra Creek or New Mexico. Apparently Canada isn’t quite finished defending the beaver’s honor because this column from Conrad Black appeared on the weekend. (Yea, I mean THAT Conrad Black, who founded the National Post 15 years ago and is the former chairman of Brittain’s Telegraph Group of Newspapers.) Guess what he thinks about beavers?
If the beaver were a contemptible animal, it would never have been adopted and would certainly be disposable now. But it is a remarkably commendable animal, possessed of a formidable work ethic. (I can’t abide rhetorical questions but am sufficiently overcome by inter-species moral outrage to ask if anyone has ever been described as “working like an eagle” or “busy as a lion,” unless they were preying on the defenseless, or, respectively, overcome by lust or narcolepsy?)
More impressive, the beaver is a natural engineer, who not only grasps but by his own adaptive ingenuity, implements the basic principles of irrigation, flood and drought control, and in most of its elements, power generated from water courses. Apart from the honey bee, which was part of the national symbolism of France under the Bonapartes, in deference to the 500,000 Frenchmen who dutifully gave their lives in the great campaigns of Napoleon, the only other national animal that has made a direct constructive contribution to a country apart from the beaver is the elephant of India, often useful in construction and both civilian and military transport.
His complete, glorious column can be found here.
Hopefully all that good beaver reading will build up your immune system for the beaver-phobia displayed here by Denise Crosby, a self-professed tree lover in Illinois. 
Recently a beaver destroyed a beautiful white birch growing ever so peacefully just a few feet from the back door of my family room. We’ve done stories over the years on the proliferation of deer, coyotes, bats, raccoons and the latest, skunks. But none of these fine-feathered or furry critters have the capacity to fell every darn tree in your yard. And beavers will keep chewing away as long as there is wood available, said Bob Bluett, a biologist with the Illinois Department of Natural Resources.
According to Bluett, scientific data seem to indicate the beaver population has grown more quickly in Illinois than in any other state, thanks to their migration from the north, where dry summers have forced them to seek new waterways.
And they are “well adapted to all kinds of urban and suburban habitats,” he tells me. In other words, they don’t really care how much backyard lighting you have. Once the TV is off and you’ve retired for the night, they’ll feel perfectly at home chewing down the tree right outside your bedroom window.
Surprisingly Denise hasn’t responded to my helpful email telling her how to sand-paint trees. I gave her two whole days to learn in private before I committed her for mocking-fodder here. Let’s hope she and Bob are so busy looking up the resources I sent to see if they’re accurate that they haven’t had time to thank me in person yet. In the meantime lets think about that highlighted sentence shall we? “Scientific data indicates that beaver population has grown more quickly in IL than any other state.” Just fascinating! What kind of scientific data, I wonder? I mean to know one state has more beavers than another it would have to be collected on a national level, right? And since the Forestry Service isn’t counting beavers and they weren’t part of the recent CENSUS I can only think it must be numbers from USDA. Of course we know USDA isn’t counting LIVE beavers so they must be counting the other kind. Lets look at the stats for IL USDA beaver killing and see how it compares. In 2009 USDA was brought in to kill 19 beavers, two with firearms and the rest with traps, which, since we’re grading on a curve, isn’t very many. I’m guessing that in 2010 might have been somewhat higher? Of course that doesn’t mean there were more beavers in IL but only means that there was greater reliance on USDA to kill them – which varies from state to state and year to year. Correlation doesn’t equal causation, as I learned in my research design class. An example? Ice cream consumption in positively correlated to deaths by drowning. So does ice cream cause drowning? (Think about it.)
So in addition to the faulty science and not giving her real solutions, the Department of Natural Resources advises her that trapping is hard work and costs a bit of money. Her thrifty son suggests shooting the beaver on the cheap. Charming lad.
Trapping can be tricky. You can apply for a license (with a couple of fees attached, of course) or turn the work over to a pro, which could run hundreds of dollars. My son said something about a .22 and a beaver hat. But Bluett points out shooting the critters is not allowed unless the animal is proving an immediate threat to you or your property.
So I tell him about the 50-pound beaver that almost killed a bulldog in the neighborhood a couple years ago. He assures me these creatures are not aggressive unless provoked; and more than likely, the pooch was the one trying to pick a fight. “Thanks for all the info,” I tell the very nice biologist. “Know thine enemy, I guess.”
Mr. Beaver, indeed, has become my foe. Not yet sure what the war strategy will be. But this is one battle I’m really sinking my teeth into.
My goodness, the entire Crosby family is thoughtful and ecologically minded! Since you love trees so much it may interest you to know that when beavers build dams they raise the water table and increase the riparian border. They also produce a natural coppice cutting when they chew trees, making the stumps grow back denser and more bushy and producing ideal nesting habitat for migratory and songbirds. I can’t think of a nicer gift to your beloved trees than a creek full of beavers.
But I’m funny that way.
