My Border Collie Lucy hated squirrels. To her they were The Enemy, to be attacked at every opportunity. She would sit and watch the bird feeder in our yard just in case one of the Enemy appeared, and if one did, woe betide him. Other creatures are to be attacked, but squirrels were her particular passion.
I thought she should have a "kill chart," like the ones they paint on the sides of fighter aircraft flown by successful pilots: she was certifiably an "Ace," with nine confirmed kills: five squirrels, three groundhogs, and a nine-and-a-half pound possum she cornered under a tree one night.
Oce one of The Enemy made a foray to steal sunflower seeds, and she put him up a tree. You can see this happen by clicking here. Be sure the sound is on! Tehya, the big Chocolate Lab, was essentially clueless about what's happening; but Tehya was pretty clueless all the time.
The squirrel in the video is a real daredevil: he seems to think Lucy would never catch him. If I'd had to bet which one would win in the end, I'd have bet on the dog.