The pod of whales, dive deep down and then start circling around to make a vortex, and all the fish get swept up into it so they are concentrated, for easy pickings, and the gulls have figured out also, that whales, are great creatures to follow , they get a snack also
I have only ever seen one whale in the wild and that was such a fleeting glimpse that I did not even realise it was a whale until someone said. A great shot and so much more interesting with the short explanation.
Can you check the image size please, looks big to me.