They are suposed to disappear quickly. I usually don't notice problem with dead hawk bodies. But you PS3 people seem to have more severe problem with things not disappearing.
On the PS3 subforum there are posts about how to deal with garbage problems. One of the posts suggests occasionally locking yourself in a house and sleeping for 30 days straight. It's the maximum time required for everything that can be respawned to respawn. It will help to keep your save files not to bloat as much.
I'm actually on the Xbox 360. Thanks for the tip you provided, but it did not work. I slept a full 31 (one extra for luck) days, made a manual save, manually exited game, and went to the dashboard. I then cleared the game cache on startup, loaded that manual save, and fast traveled to the Solitude docks or whatever. I walked up the Solitude gates, entered, and tada! The hawk body was still there in the same place. I realize now that the hawk bodies are permanent for me.
Fortunately and unfortunately, I do have one save file from before shooting any hawks, but it's the earliest save on the list. I would have to go back and get a couple unique armor pieces again to mostly catch up. It may sound over-the-top to do because of a couple hawk bodies, but I think I will actually do that, because I want the game clean as reasonably possible. Such is the nature of not having access to the command console...
