Who Ate These Butterflies? Close inspection of a dead butterfly gives a clue as to its predator: Photo Predator Clue #1 Black-headed Grosbeak The monarch's abdomen is entirely missing. #2 Black-backed Oriole The monarch's abdomen is present, but it appears to be "unzipped" (slit open) and the thorax is gorged. #3 Black-eared Mouse Caches of butterflies are found on the ground, and only the wings remain. Photos of predators copyright Dr. Lincoln P. Brower, Sweet Briar College Search Journey North Copyright 1997-2012 Journey North. All Rights Reserved. Questions or comments? Contact us.