Exactly that. I was standing 3 tiles away looking at it and as soon as the elk died it dissapeared.
Okay. I tried reproducing this, but failed. Had an elk bleeding, waited until it died, but it didn't vanish - so it's something else than bleeding what caused the issue.
What kind of area it was where did happened? I'm thinking of possibilities that might have interfered.
It may be very, very tricky to have this reproduced, but if it ever happens again it would be great if you (or somebody else) could save the game right after the incident and send it over to me for further investigation.