Beavers are felling trees along the southern tip of Bloodroot Island in Hudson Mills Metropark.
This past Saturday I sat in on a presentation in the park’s activity center about the beaver couple that have recently taken up residence along the banks of the island. And true to their reputation, they’ve been busy.
First off, I didn’t know there was an island at Hudson Mills, much less that it was called “Bloodroot Island,” and even much less (if that is at all possible), that there are no Bloodroots on it. Bloodroot is not a root at all, but a flowering plant with poisonous red juice. But we’re not here to ponder Michigan’s toxic flora. On to The Beavers of Bloodroot Island.
“Beavers are kind of incredible animals. They’ve been around long before Europeans got here. In fact there was a time when there were 400 million in North America,” began Interpretive Ranger Mark Irish. “But then something happened … (dramatic pause and I felt myself leaning forward in my seat) … Europeans showed up!” he exclaimed.
Before the Pilgrims and even before Columbus, there were ships coming from Europe and fishing for cod off the shores of America. The native residents got curious and paddled out to the “big canoes” wearing their soft, water repellant beaver fur to see what was going on. The fisherman loved the fur. The native citizens loved the tools and ornaments. A trade was born.
Passing around a beaver pelt for us to examine, Mark explained and we saw, the beaver actually has two layers of fur. The top layer is hair. The bottom layer is woven in among the hair and has a felt-like texture. It is this base layer that hat makers around the world busied themselves like beavers with making stylish hats for the well-heeled of the day. Demand for beaver fur exploded. Detroit actually began as a French fur trade colony.
By the 1930’s, the 400 million beavers had been trapped down to 100 thousand and those were mostly in Canada. Here in southeast Michigan the beaver completely disappeared from our polluted waters in the 1960’s. But you just can’t keep a determined and busy rodent down, especially North America’s largest.
“Guess who just got back today
Them wild-eyed boys that had been away” – Thin Lizzy
About ten years ago beavers began to be spotted paddling and waddling about our neck of the woods once again. Saplings were once again being chewed and lodges were popping up here and there. “The beaver population is now estimated to be around six million,” Mark said.
Mark then went on to explain how their teeth grow six inches a year. Chewing wood keeps the teeth ground down to a manageable size. “In zoos if they don’t give them some wood to chew on, they have to put them in a headlock and file their teeth down,” he said pantomiming holding a beaver in a headlock and filing its teeth down. We all laughed. Mark was fun.
When it comes to all that wood chewing, “It’s not the wood they want to eat,” he explained. “It is the living tissue of the tree is just under the bark. They’re eating that and throwing the wood away.”
“But what else do they do with the wood?” he asked the kids. A few answered, hesitating with nervous glances at their parents before using the word “dam.”
Beavers construct their famous dams by piling up sticks and mud and then digging out a cavern in it. The well insulated lodges are relatively warm from beaver body heat throughout the winter. Hibernating animals such as snakes and turtles will often use the dam to hibernate in the cold months. The beavers are strict vegetarians and let their winter boarders dream in peace rather than in pieces.
Ranger Mark told us of one fellow who inserted a camera into a beaver lodge and found that beavers spend up to eight hours a day grooming themselves; something I’m sure the furriers appreciated back in the day. What the beavers are actually doing is taking oil from a gland on their backside and slathering it around like suntan lotion. The oil is what keeps them dry. Staying dry is what keeps them alive in the frigid water.
“There’s a lot of things that look like beavers and get mistaken for them in the park,” Mark explained “Probably the most common one is the muskrat. I like to think of them as a mini beaver. They do a lot of the same things as beavers but they don’t do it with wood. They do it with cat tails … another one is the mink … the worst one is the woodchuck.” A lot of people report beaver sightings when in fact it is something else. But if you were to put the animals side-by-side, you could easily tell the difference; unlike Dolly Parton who once entered a Dolly Parton Lookalike Contest and lost to a man dressed-up like her.
Besides the built in wetsuit, beavers have other aquatic anatomical advantages. They’ve got a third eyelid that acts as built-in swim goggles. Third eyelid, meaning they already have two. I should have asked Mark about that.
Beavers can close their ears which I’m sure drives parents of teenage beavers crazy and something I’m not so sure human teenagers are unable to do. They can close their nostrils which is something we could all appreciate being able to do at times. They have webbed feet and a big tail used for swimming, not packing mud.
For me, perhaps the most interesting beaver fact was this:
“The thing that causes them to start putting stuff on a dam is the sound of running water,” Mark told us. “And they’ve actually done experiments where they’ve played the sound of running water and the beavers start adding tons and tons of stuff to a dam that is already rock solid.”
“They’ve done other experiments,” he continued “where they take a pipe and they run it through the dam where it will drain without the sound of running water and every drop of water will come out of there without (the beavers )recognizing there is something wrong.”
And here I always thought beavers were all about the civil engineering task of creating new lakes and ponds to beautify the landscape for the appreciation of all animal-kind; sort of the Gustave Eiffel of the animal kingdom. It was more than a little disappointing to learn they simply want to stop the annoying sound of a happily babbling brook, something in which I find great pleasure and solace when backpacking. But in their shoes, or webbed feet as it is, I can’t stand a drippy faucet either.
Mark speculates that we won’t be seeing any beaver dams along the Huron River anytime soon. He suspects these two beavers are “bank beavers” who burrow into a bank underwater and then up. If the water level rises, they burrow further up. If they poke through the ground surface, they build a lodge on top of the opening. There are no signs of dam building or dry ground lodge building yet on Bloodroot Island.
The indoor part of the presentation was coming to an end and Mark was going to take us out to Bloodroot Island for a firsthand encounter with chewed up aspen and cottonwood, beaver slides down to the water and anything else we might find. And if that wasn’t cool enough, on our short walk from the parking lot to the island we would see a bald eagle flying over the river looking for fish and a pileated woodpecker flitting about from tree to tree.
“People will see what the beavers are doing in the park and come to the office upset about it saying, ‘What are you going to do about the beavers!?’” Mark tells us in closing. “Our response is … (dramatic pause and I felt myself again leaning forward in my seat) …
… “we’re going to let the beavers be beavers.”