The missing head and wing would seem to be more in line with scavenging, and there would be no reason for the owl to remove these body parts to consume the body cavity muscle.
Can you add abstract heading?
Change to ": a possible incidence of intraspecific predation or scavenging."
but these are two separate instances. So "twice", correct?
change to "the owl was injured, "
change to "would seem"
I would suggest a rewrite of this ultimate sentence to reduce comma use.