We have 2 chipmunks that frequent our backyard. They regularly hang out under our bird feeders helping to "clean up" the spilled seed. They also run across our patio entertaining our inside cats. They are sometimes out together and sometimes I see only one at a time. Today, around 12pm, one was sitting in his regular spot on the edge of our patio and my cousin was taking photos of him. 4 hours later, I went back out and what looked like a black, wrinkly, crusty rat looking thing was sitting where "chippy" usually does. Then it started "acting" like chippy. What could have happened to him in 4 hours? Could it be his partner with some kind of skin condition? Or could he have been burned? Is there any way I can send a photo?