Northern Flicker Hard at Work on the Tuolumne River

I see Northern Flickers (Colaptes auratus) quite often along the Tuolumne River Parkway Trail in Waterford, but they are usually quite busy flying from one tree to another. For a woodpecker, they spend a lot of time on the ground instead of pecking away at trees. It turns out they like to eat ants and other insects and will peck at the ground to get them. That's what made today's sighting a bit interesting. This one was working very hard at a gash in the cottonwood. I'm guessing it was excavating a nesting hollow. I was getting frustrated trying to get a clear shot of the bird at work and finally realized I would maybe have better luck with a video, so here you go...