The little guy squeezed in when the feeder was less than half-full, ate too much (hence the chubby cheeks) and found himself trapped. In order to prevent having a chipmunk fatality on my conscience, I take care to keep the seed level above the highest possible chipmunk entryway. This was working just fine until an acrobatic squirrel entered the picture. As you can hopefully see (below) this little bugger is part possum, part Olympian. And while I admire his seed-stealing skill, he's shaking things up quite a bit and spilling all the seeds - which leads us right back to the chipmunk trap.