Streamside Traffic and Ghosts of Creatures Past

I was happy to discover yesterday that the banks along the creek behind our house gather some interesting signs of animal traffic. There were deer prints, of course, sometimes quite deep in the mud (I think there's something of a deer highway through these woods):
 

And little hand-prints, which (I'm pretty sure) were left by a passing raccoon:
 

The bank with these tracks was also dug up in several spots. What tasty treats might a raccoon find buried in the mud and rocks?
 

The creek's banks held another type of animal artifact, again (I think) from a raccoon, but this one long dead:
 

Skulls are definitely interesting -- look how bright and sharp those teeth are -- but I didn't feel the need to explore this object more closely. It'll stay on the bank until the water rises again and carries it off somewhere else.

Speaking of long-gone creatures, I've been keeping an eye out for Yellow-bellied Sapsuckers, because the signs of these birds are all over our yard. This tree in front of our house features several conspicuous lines of sapsucker holes:
 

And I've come across a few trees in the woods that are about as covered with sapsucker work as it's possible for a tree to be:
 

It must have taken years for the sapsuckers to so thoroughly work over this tree:
 

But all the holes I've seen are pretty old by now, and I haven't come across any more recent signs of these birds. I wonder why this former sapsucker territory is apparently abandoned now.

It's always interesting to see signs that creatures have left, although I still prefer to see the creatures themselves!