There is a flat rock covering an old well by our hickory tree, creating a good flat platform that is little higher than the rest of the garden. Both the red squirrels and the chipmunks like to take their food there because it is a safe vantage point. The red squirrels (Tamiasciurus hudsonicus) are a different species from the ones in England, and are very aggressive. This time of year, they are gathering hickory nuts for the winter. They chew off the green outer casing, then gnaw through the very hard nut to get at the kernels inside.
The squirrel left for a bit and the chipmunk came along.
But then the squirrel came back, and took a dim view of this intruder. The much smaller chipmunk, after a brave show of aggression, beat a hasty retreat.
And the squirrel did a victory dance.