I saw a very unusual sight this weekend - walking Mt Annan Botanical Gardens and heard a huge racket of birds, and went to investigate, hoping for an owl. But instead I found a tree full of currawongs and ravens, all attacking a hapless grey-headed flying fox. He was just hanging there (solo, which is unusual) and the currawongs lined up on one side to peck him, while the ravens came at him for the other side. He didn't fly off (as you might think) but raised an almighty skwawking himself, and batted at the birds with his wings - but he was definitely getting the worst of it, and after watching in increasing dismay for 10 minutes (it was really quite distressing) I left before the finale.
Any idea what was going on there? Have never seen ravens and currawongs cooperating like that, other than mobbing a raptor or similar - could they have seen the bat as a threat? Prey? Were they just being bad corvids? Or was the bat sick?
