This fern was found in a garden under the partial shade of deciduous trees on campus. However, the lady fern is also found at all elevations. It looks similar to the wood fern, but this looks triangular overall. There does not exist any sori (cluster of spore-producing receptables on the underside of a fern) on this particular one just yet because it is only the early spring.
Must be a common type of squirrel, see these all over the city. Apparently these guys are from the east and mideastern U.S. They build a nest that may look like a bird's nest. The ones on our campus dig into garbage cans and berries during the spring.