Scratches on the floor? Who, me?

A few years back, Papa Bear worked late into the wee hours of the Xmas holidays to put down a hardwood floor in the living room. A few months after Spike arrived in the house (coincidentally also during the Xmas holidays .. but a couple of years after the floor) we started to see little scratches on the floor by the window. These were pointed out to Papa Bear (in the context of "look what your cat is doing!") but he was insistent that the scratches must have come from one of the boys pushing the chair back and then dragging it forward again. It wasn't long before the mystery was revealed. Every time a squirrel or rabbit walked by the front window, Spike would desperately try to run after them. We would hear a loud scratching sound and when we looked down we saw the back legs going like crazy, with those solid claws digging into the wood floor. Once the excitement is over Spike climbs onto the wood stand and looks like butter wouldn't melt in his mouth. "Those scratches on the floor - who, me???