I had to walk along the sidewalk slowly, not looking at the squirrel, and bring the camera to my eye before very casually pointing it in his direction.
Squirrels know eyes: A pair of forward-facing eyes pointing right at them screams "predator!" and the little critter would have scooted around to the other side of the trunk and on up the tree.
Squirrels don't, however, know what a camera is. We had a very "ravenous bugblatter beast of Traal"* situation going on. As long as he couldn't see me looking at him, he was wary, but not panicking.
*If you haven't read Hitchhiker's Guide, why not?
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