Excellent shot, Rob, and an even better story

This is definitely not your run of the mill squirrel shot. It looks like you climbed the tree ahead of the little guy (or gal). So, great viewpoint, and you caught the squirrel scrambling up the tree, showing his claws in full action, very well done there.
I'd say dial the exposure down a bit, in particular his 'arms' are slightly overexposed.
You just managed to get his eye in focus. I'd rather his back were in focus than the bark, but I suspect the little guy was moving rapidly, so you didn't have time to spare on fine-tuning much of anything
Love the composition. Placing the tree on the diagonal really emphasises the action of the shot.
The BG is a bit distracting, perhaps you could tone down the bright areas, e.g. clone from the green.
This is excellent work, Rob, a very unusual view of a squirrel, i.e. from above, which makes it an especially eye-catching image. You worked hard for this one, + you got it! Very well done