The Tree Sparrow is easily overlooked in the south of the country as it is not as numerous as in the colder north. Smaller and dumpier than the House Sparrow, it has a pure chestnut head and a small black cheek patch, commonly referred to as its ear. It nests in holes, usually in trees and quite often in old Nuthatch nests.
Joomla Gallery makes it better. Balbooa.com