Strange Bird?

Today was again cold and wet, so this picture was taken through the kitchen window, but the weather did not discourage this squirrel. He might reasonably have been sleeping somewhere in the warm, rather than raiding the bird feeder, despite the dedicated squirrel box feeder being only a metre away. The bird feeder is effectively squirrel proof with perforated steel plate, which is sized for bird's beaks not squirrels' teeth.