How do animals find their direction within their environment? Ground squirrels use information on the position of the sun when they hide and then return to retrieve their stash. The position of the sun serves as a reference point for the animals. Squirrels store their food reserves in several hiding places. Squirrels probably use the position of the sun as the most important cue to roughly adjust their direction of movement. Squirrels that were given food moved in an almost straight line either towards or away from the sun to find a suitable hiding place. Then it was noted that almost exactly 24 hours later the sun was in virtually the same position in the sky, the squirrels would get their bearing from the sun and set off to retrieve their food. It was also noted that if the squirrel returned earlier when the sun had the same mirrored angle, it could also retrieve its food.
http://www.delta-optimist.com/opinion/blogs/blog-squirrels-are-on-the-compass-1.2342110