Here's a large fully-fledged "brancher" -- a juvenile out of the nest, but still spending time in the nest tree -- aggressively grabbing the bill of feeding parent. This is behavior that stimulates the adult to regurgitate the food item -- here what looks to be a pretty large fish -- for the young bird to eat. It looked in this case that the parent was requiring the young bird to do a lot of work for the food. Maybe coming to the end of the feeding period -- "good to go"?