Depends on the species of squirrel. My guess is that an adult (American)
red squirrel could easily slip in, a grey squirrel maybe, fox squirrel less likely,
without some immediate motivation (such as evading a predator outside,
or a large, obvious pile of peanuts on the inside).
Red squirrels make storage middens, and they've been known to make them
in houses and outbuildings. I've heard stories about people going to open
up their cottages Up North and finding heaps of cones stashed by red
squirrels inside. And I once noticed one going in a small hole at the top of
the neighbor's foundation, which apparently was going up through the wall
to stash food in the attic. These little guys are tough--I've seen them stand
up to and even run off much larger fox squirrels.
I watched a 'love-sick' male fox squirrel follow the female of his desires
around the other day, but she was having none of it and rightly so; despite
all his frantic tail-waving and posturing, he was inferior in size to her.
--
Pat in Plymouth MI
"Yes, swooping is bad."
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