If they're up high like that looking for fish they would be looking DOWN. These bears are looking UP. I don't think they're hunting for sea gulls. I think they're photoshopped.
Ummm...maybe they're looking at the photographers trying to decide which one to have for lunch.
The picture looks to have been taken from somewhere higher up than even the bears - maybe they're looking up at the photographer or whatever he's standing on to take the shot (a ship, maybe?). Polar bears are fearless and see humans as nothing more or less than meat popsicles.
From the specials on polar bears I have seen, they are sniffing the air with their heads up. They smell things from miles away.