Beaver woes

Photo by Mark Giullucci

It’s a rite of spring, that first walk around the property after the winter has ended. Unfortunately, for some cottagers, that’s when you discover what nature has done to the place while you were away.

Heavy snow and high spring waters can take their toll, but few natural forces can change the look of a place as thoroughly and as quickly as a hungry beaver. Mature trees might define the look of your waterfront, but they can be brought down overnight. Even worse, while beavers are expert loggers, even experts sometimes misjudge things and bring a tree down on top of a boathouse or cottage.

There is no quick fix once the trees are down – all we can do is plant new ones and wait a few decades. But there are a few things that can be done to make it less likely to occur.

For starters, it helps to understand why our national rodent behaves the way it does.

Beavers eat twigs, leaves and the soft inner bark called cambium, which they strip from thicker branches and trunks of trees. The remaining woody stems are either left to float away or are used to build dams and lodges.

Lodges are found all around Muskoka, on lakes and rivers alike. They’re incredibly sturdy constructions of mud and wood, piled on the shore so they’re dry inside, but with an underwater entrance so the beaver family can enter and exit in safety.  It’s not unusual to show up in the spring and find that an enterprising family of beavers has been building a lodge in or around the boathouse. No doubt they think that humans are well-meaning and inefficient builders, but they do certainly appreciate the fact that our bubblers give them access to open water in mid-winter! Tree-felling goes on year-round, but is particularly pronounced in the late fall as the beavers build up underwater food supplies. Working mainly at night, they drop the tree, nip off the choice branches, and drag them underwater to a muddy spot near the lodge where they can feed all winter long. In spring, they get back to work in earnest, savouring the fresh greenery after months of eating stored food.

There are a few ways to prevent – or at least discourage – beavers from feasting on your trees. Trapping and relocating beavers is not one of them: even without worrying about legality or ethics, it’s simply a temporary fix that only lasts until a new family of beavers moves in.

Protecting the trees can only be done on a tree-by-tree basis, so it’s best to focus on the trees that are most at risk.

The first step is to assess the kinds of trees you have along the waterfront. Beavers have incredibly sharp teeth and can fell just about any tree, but they have a marked preference for some species. Aspen, also called poplar, is a favourite food in Muskoka. Oak, maple and cherry are also often brought down, while hemlock, pine and other conifers are rarely touched. There are also ornamental trees such as weeping willows which aren’t native to Muskoka, but which beavers find delicious.

The only surefire way to protect the trees is to wrap them with wire mesh. Chicken wire will rust out – it needs to be something more sturdy, such as a 2”x4” fencing. We will wrap it to at least four feet high so the trees are protected even when there’s snow on the ground.

If you really don’t care for the look of wire-wrapped trees, there are other options that have varying reports of success. Abrasive paint can be quite effective – get some paint that matches the colour of the bark, mix it with sand, and brush it on the trunk. It’s harmless on mature trees, but there have been reports of the paint actually killing tender saplings.

A less durable technique is to mix cayenne pepper with vegetable oil and brush it on the trunks. There are also commercial repellents that give the trees a bitter taste. These need to be re-applied every year. Reports on their success are mixed, but they may deter beavers and encourage them to eat elsewhere.

And ultimately, that’s the goal: deterrence. We’re sharing the lakes with beavers and many other creatures. We only need to discourage them from taking “our” trees, and let them feed freely on the many miles of undeveloped shoreline.

Posted in Connecting with Nature.