Wow, I didn't know that. The first time I saw one was up in the Enchantment Lakes in Washington State. We came around a corner in the trail and heard the squirrels making a furious racket high up in the Douglas Firs above us. I remember thinking "hey, we can't be that scary, what gives?"

We turned a corner around one of the Dougs and there was a big Pine Marten scrambling up the bole of the tree, chasing squirrel for lunch. Mystery solved!