Originally Posted By: Marc Ret
Rookhawk

Of the raptors in question, what percentage of their diet is from scavenged carcasses?

Marcus


That's a difficult question to answer without huge study sizes over long periods of time. What I can tell you is in winter months in SW Wyoming and NE Utah, over 2-4 week observation periods, over 6 years out of the past ten, I observed as follows:

Eagles and Buteos eating from roadkill and gut piles hundreds upon hundreds of times. In that same observation period I saw predation on live quarry only a few dozen times. During harsh conditions wildlife will return for weeks to the same frozen carcass until there is nothing left but bones.

Contrast this with raptors east of the Mississippi where scavenging is much less common for these same species.

Sorry I have no formal study to point you to.