Guessing bobcat or lynx...not sure mountain lions are this far east,
plus too big to fit in dollhouse coop.
If you want to learn about mountain lions in the US, read this book, it's excellent:
Heart of a Lion: A Lone Cat's Walk Across America by William Stolzenberg
Aart, I have a neighbor about 2 - 3 miles away who had footage of a young mountain lion hanging around his pond 2 years ago. An other neighbor had a face to face with a mountain lion about 10 years ago. Our MDIFW states that they are not in Maine, but these 2 sightings convince me otherwise. If they acknowledge that they are here, then they have to have a "management plan" not to mention the public reaction.