This June I took a multi-week roadtrip to the Methow Valley to work with the Methow Beaver Project at their facility in Winthrop, WA.
I arrived with a big box of potential and purported deterrents, a few gallons of paint, and a dream. The dream was that something in that box, when mixed with paint and applied, would convince beavers not to chew on trees.
Cliff Notes version: nope, at least not in captivity when there’s nothing else available and you can’t give them too many trees or they’ll build a ramp and escape.
Working with captive beavers awaiting relocation, I collected their favorite food (aspen trees) in their favorite size (2 years old) and presented the sticks with foliage attached and painted on the (non)deterrents as high up as they could chew. The sticks were anchored in metal tubes attached to a feeding platforms, 4 to a side, a couple feet apart, with control and treatment sticks randomly assigned a position using a random number generator. The beavers had all the rodent chow and water they could want, but nothing else to chew on except the plywood on their ramps and the undersides of the roofs of their hutches.
As you’d expect, they ate all the controls every time, starting with the first night. As you might not expect, they also ate all the treatments. I tried 20 different things, and nothing worked.
50% pure capsaicin (thanks to Texas Creek products!)—chomp chomp chomp, no visible distress or reaction. Bittrex, the bitterest substance known to man—no indication they even noticed. Tanglefoot got a couple seconds of paw washing, but that’s all. The big surprise for me: sand, both large and small grains—crunch crunch crunch. Seems to work in practice, but does it hold up in theory, professor?
Casein, eggs, Liquid Fence, grape Jell-o (for the methyl anthranalite), hydrated lime, citric acid, the list goes on. I’ve got some video that’s worth seeing, but no answers yet. I’m reluctant to start field trials because the variability is so extreme and unavoidable, I funded this out of pocket which was kind of expensive, and it turns out I kinda suck at science.
But it was a super cool field trip, I loved the Methow, the Beaver Project and Hatchery folks were incredibly helpful and supportive, and I’m interested in extending the study. I’m just not sure how yet, and need to work my day job for a while longer to save the money for another run at the problem.