Mountain Beavers and Control of Mountain Beaver Damage (2005)

We have a number of urban beavers in our neighborhood, and their work is quite impressive to watch (the animals themselves keep out of sight). Within a few months, they've managed to thoroughly decimate the trees around them, and remodel the creek they live in.

Of course, the beavers would reject the idea that they are causing "Damage". At least in the longer term, the landscape they live in turns out just fine. It's just that beavers have rather different ideas how that landscape should look, in terms of flooding, tree mix, etc, and have the means and the determination to impose their preferences on their habitat.

I can see how that would distress some owners, but I'm glad they are being tolerated in our city.

I have the dam beavers at my place. Sometimes they are more active, sometimes they are less. When they are active we find we can usually avoid problems if we take unwanted dams apart early. If you go out every morning you can take them apart in under five minutes, but once the water level rises they get faster at building and you will have to work a lot harder.

From time to time they try to block our culvert pipe which breaks the usual rule of "remove sticks from the downstream of the dam and then dig out the clay" because getting downstream of the dam means working inside the culvert pipe which is more tiring than working outside of it.

I had a nice pond which was choked with freshwater seaweed, then I got triploid grass carp to eat the plants, and the year after that the beavers moved in. I tried swimming around and noticed a lot of beaver turds, then I felt an explosion and realized that one of the beavers slapped his tail ten feet from me.

Then I went in and read that swimming around in a pond full of beaver turds was how you get Giardia so I quit swimming there.

For those unacquainted with mountain beavers, they are only distantly related to the beavers that build dams. They are also the host to the world's largest species of flea, which can reach sizes of ~1/4"!

Here is a surprisingly hilarious account of the search for a live mountain beaver flea specimen: https://www.nytimes.com/2014/07/29/science/the-great-giant-f...

I knew about the dam beavers but had no idea there was a species that didn’t build dams but instead burrowed. I would probably mistake them for marmots if I saw one.

California subspecies is endangered, and I can attest, having grown up in Tahoe on a street named Beaver Dam Trail, we haven’t seen beavers in the valley for decades.