Beaver Guru, professor emeritus at SUNY college and author of 
these beaver bibles: has decided that retirement doesn’t mean an end to teaching about beavers. He has a great article in Northern Woodland Educators about beavers ‘recycling’ plant defenses for the own ends.
Arms Race in the Woods: How Beavers Recycle Tree Defenses
Around a beaver pond, we sometimes catch a whiff of beaver odor. People have described it to me as smoky, woody, or like tobacco. It may waft over from the lodge, or it might emanate from scent mounds – little piles of mud by the water’s edge. Beavers make scent mounds by dredging up mud from the bottom of a pond, then carrying it up on land in their front paws while walking upright. The beaver drops the mud, then squats over the mound and applies castoreum from glands near the base of the tail.
Compounds from a number of trees in the beaver’s diet end up in their castoreum. Benzyl alcohol occurs in aspens and poplars, benzoic acid in black cherry and scots pine, and catechol in common cottonwood. In summer, beavers eat aquatic plants such as pondweed and pond lilies – the alkaloids that these plants use to deter insects also end up in the beaver’s mix.
Beavers cope with plant chemicals in different ways. They have in their saliva a protein that binds tannins and renders them harmless. They deal with other compounds by breaking them down into their component parts: when they ingest salicin – a bitter chemical in willow and poplar bark – the salicin molecule gets broken down into sugar and, eventually, salicylic acid. (Beavers are not the only animals that have this trick – leaf beetles also ingest salicin when munching on willow leaves. They use the glucose as a nutrient and the salicylic acid for defense against predators, such as ants.)
It’s a great article, go read the entire thing HERE. Of course I’m not surprised, because as we all know, beavers are awesome. Mind you, in 7 years of watching beavers with a dozen beaver experts checking our territory we have never YET found a single scent mound in all of Alhambra Creek. But I’m sure if Dietland made the trek to Martinez he’d know where they were right away!
And now to make sure you start your weekend with a sense of purposeful compassion and civic ingenuity, I’m sharing these awesome photos from the Isla Vista paddle out (organized by the UCSB surf team) in memorium of the horrific killings there last Friday by a young man who said women shouldn’t be allowed to choose their own sexual partners. Look at these photos and tell me that they aren’t a reminder of how awesome many humans can be in response to monstrosity.
Not big enough to make a difference? Let’s back up a bit.
