Cavity Nesters in Canatara!

I saw my first Yellow-bellied Sapsucker of the year on Thursday! Yellow-bellied Sapsuckers drill rows of tiny holes in live trees which attract insects to the leaking sap. The Sapsucker later returns to feast on the bugs that are drinking the sap from his drilled holes!  Many creatures depend upon these "sap wells", including hummingbirds who time their spring migration in some parts of Canada with the return of these birds. (Cornell Lab, All About Birds)

The Sapsucker followed a Downy Woodpecker to a few trees.

Nearby, a pair of White-breasted Nuthatches made many trips to a natural tree cavity, bringing nesting materials into the hole. He closed his eyes as he squeezed through the opening. White-breasted Nuthatches don't seem bothered by nest holes considerably larger than they are. (Cornell Lab, All About Birds)

Another stick into the hole.

After one of the Nuthatches flew inside the cavity, a Red-bellied Woodpecker showed up to inspect the work. I'm pretty sure he wanted to go in but chose not to battle the little Nuthatch. I was really hoping the Nuthatch would pop up for a picture, but no such luck.

After the inspection was done, the woodpecker flew to the next tree and entered an unoccupied hole, probably looking for food.

A friend (thanks Dave) pointed out the yellow marks on the front of a house at the edge of Canatara Park. A Red-bellied Woodpecker has been drilling holes in the siding this spring and the home owner chose to fill the holes with yellow foam. Drumming on loud surfaces makes a satisfyingly loud noise that proclaims the bird's territory and helps attract a mate. Once breeding has begun, the behaviour is likely to stop. (Cornell Labs, All About Birds)