I had a Dachshund who wasn't the least bit scared of squirrels. He spent most of his life trying to kill them. I'm not sure if he ever got one, but he never quit trying, and in time he began using "stealth" methods instead of the standard old "CHA-A-A-A-RGE!!!!!!!" routine. He would lurk silently at the bottom of a large tree for hours, not moving a muscle, just hide in the foliage and wait for a squirrel to descend...then ZAP!!! I saw him come within a micron of getting a squirrel one day, but the squirrel just barely evaded his lightning fast lunge and snap. It was tremendously upset, of course, and rushed up a different tree where it cursed him loudly for the next 15 minutes or so... ;-)

Squirrels do not expect Stealth Dachshunds.

A whole series of chimpmunks met a sudden and grisly end in the jaws of this same Dachshund. He would lurk silently around a corner of the house...waiting...and some poor chipmunk would eventually come bopping merrily around the corner and...CHOMP!!!!! Finito.    Squirrels weren't that easy, as they don't tend to do the around the corner of the house manueuver. They think more in terms of the vertical axis than chimpmunks do.