Oh my that really IS a mouthful. I hope he didn't choke on it. Do you know what kind of fish is it by any chance?
His mama should have taught him to not bite off more than he can chew! We have seen herons catch a fish and take three or four "gulps" to down it. I bet the gull managed to dine, if not in style, at least to dine well.
Eileen, I have been informed by a friend who was in charge of the fish etc at the museum, that the fish is a Starry Flounder, Platichthys stellatus. The same species as the one I took with an otter.