Where do they go?

Whilst out walking Barney in howling winds and pissing rain, a thought struck me (right between the eyes, in fact). Where were all the squirrels that normally send my trusted hound bonkers taunting him to chase them up the trees?
Were they cowering in bus shelters?
Is there a communal Hobbit house where they all congregate and chat about the weather?
Had they gone away for the weekend to Ibiza, perhaps?
Maybe Secret Squirrel (remember him?) had enlisted them to track down some suspect radiation trails.
Wherever they were, it wasn't in our woods. Didn't stop Barney charging around like a dog possessed though.