We have a very tiny squirrel with stripes on its back. We have never seen it climb a tree, but scampers quickly on the ground and appears to be nesting in some low bushes near our house. It almost looks like a chipmonk with a squirrel tail. What could it be? Also, we have what we think is a flying squirrel living in a blue bird house attached to a tree and he comes out and flattens himself against the tree trunk and will also fly to the nearest tree. Is this indeed a flying squirrel? Thanks.

Chipmunks seem to like burrowing close to buildings, particularly if there are bushes or other cover planted close to the building. My guess is that you have a chipmunk. The other possibility would be a thirteen-lined ground squirrel. However, these squirrels prefer a more grassy habitat whereas chipmunks prefer a more woody habitat. The animal using the blue bird house does sound like a flying squirrel. If you can get pictures of the animals, I can help you identify them. If you go to the page below you can see photos of a chipmunk (first photo) and a thirteen-lined ground squirrel (second photo). If you click on the photo they enlarge and provide a brief description.

http://web.extension.illinois.edu/wildlife/directory_show.cfm?species=groundsquirrel