Beavers on Lake Beulah
Have you seen a beaver swim past right around dusk? I have. For many summers, almost every night, a beaver swims by around 8:00PM. Where the critter came from and where it is going, I don’t know. Some lake folks, whether having seen a beaver or not, are aware of their presence because they notice trees missing from their property. Not good!
It is interesting to note that by 1730, 100 years before European settlers arrived here, beavers were entirely extirpated from SE Wisconsin. The only real currency of this area’s Native Americans was beaver pelts, and they essentially wiped them out. By 1900, beavers were extinct across the entire state of Wisconsin. But beavers, the largest rodents in North America, have been reestablishing their presence. And while in some ways it’s cool to have such a creature living nearby, the beaver isn’t making any friends by cutting down our trees.
Beavers’ most distinguishing characteristic is their tail. This serves to stabilize the animal while tree cutting. The tail also serves for fat storage and gets thicker in the fall. A third use is as a rudder while swimming.
The beavers around Lake Beulah seem to be willing to cut down any kind of tree, a few of which they use for food. For nourishment, they can extract carbohydrates from soft wood trees like aspen and willow, but in summer, 90% of what they eat is aquatic plants such as water lilies.
Beavers build their lodge for protection. Young beavers, called ‘kits’, stay together around the lodge as a family unit for two years. Lodges are made of sticks and mud and have an air vent. First, beavers build a pile of sticks, and then excavate a tunnel and reinforce it with mud. There are several beaver lodges around the lake. Be careful around them in winter, as due to the warmth inside, the ice is thin.
Being rodents, beavers must gnaw wood to keep their teeth from getting too large. I recall seeing a beaver skull at the Milwaukee Public Museum with teeth that had grown so long they grew through the lower jaw. That beaver didn’t live long. I’ve seen stumps from dozens of trees cut down by beavers, and not once was a fallen tree left behind. Amazingly, the trees, sometimes pretty large, were dragged down to the lake and taken back to a lodge. That took a strong and determined animal! To protect their trees from beavers, the WIDNR suggests landowners consider putting metal skirts around the base. While this works, it isn’t always practical.
It is perfectly legal to trap beavers around Lake Beulah, and trapping has been going on for some time. Not too long ago, there was a news report of a 108-pounder trapped near the lake. As long as rules are followed, anyone can do it, but it’s best to go with a pro because of potential unintended consequences like a dog being killed. While live traps are sometimes used, the main trapping method is using a body-gripping ‘conibear trap’. These traps are placed just below the water surface.
Once beavers decide to chew on a tree, unless it is protected they will likely take it down.
Despite the damage they cause, beavers are considered by some to be the most important of keystone species. The term keystone is used for species that have a disproportionately large effect on the natural environment around them. Beavers work to stabilize the ecosystem.
With beavers, there is more biodiversity, better water quality, less phosphorous loading, less erosion, and more habitat for wildlife. Interestingly, around the state 90% of great blue heron rookeries and osprey nests are in beaver ponds.
Source of information: https://www.wpr.org/shows/how-beavers-benefit-our-environment