Both of these nests are occupied by the same species. The one on the left is in a Peterson box, at a trail I manage at the local solid waste transfer station. It has a base of moss, with fur, topped by feathers, fairly flat on top. The one on the right is in a NABS box in a meadow. It is 100% pine needles, fairly flat on top. Both were in use in the month of June.
SEE: Who Trumps Who, Nest site competition
ANSWER: Snap, I forget! But am pretty sure the mossy one was a Tree Swallow takeover of a Black-capped Chickadee nest? Bottom one Tree Swallow? Sorry!
Never say never because they will fool you every time!
– Malinda Matsuko
