Each of the evangelists used the same term in their respective accounts of the feeding of the five thousand and the four thousand (Matthew 14:20; Matthew 15:33; Mark 6:42; Mark 8:4, Mark 8:8; Luke 9:17; John 6:26) to describe that people were satisfied. The word itself does not necessarily imply that these birds’ stomachs were bursting. The fact that they all had their fill means that there was flesh left over. That in turn points to the enormous number of the dead, that is, of those who aligned themselves with the beast and the false prophet.
21 And the rest were slain by the sword that came from the mouth of him who was sitting on the horse, and all the birds were gorged with their flesh.