Chipmunk in overhead run 11th September 2012

Is that actually a chipmunk or some kind of white squirrel? Also, are the overhead runs used in the winter or is the wire too cold for the animals?

chipmunks are squirrels

here's another photo from Axe Valley showing a white one with a normal one: http://www.zoochat.com/1367/chipmunks-11th-september-2012-a-293611/

I'm assuming these are Siberian chipmunks?

As far as I know they are Siberian, but I did not check the label. I believe the Siberian is the usual "British" Chipmunk, but I do not know for certain.

Regarding the runs, I do not know if they are used in winter. The metal could get cold, but then the runs could get more sun as they are higher up so the animals could go up there to a warm spot. I should have thought the animals would be best left to their own devices where using the runs or not is concerned. The park is closed in the very depths of winter so there would be no visitors hoping to see the runs in use anyway.