Ring-billed Gulls with shells

I watched dozens of gulls yesterday in the middle of the lake on a sand bar with shells/clams on it. They would methodically take one in their beak and fly up and hover and then release it! I thought they were doing this to break open the clams on the sand below, but they would dive bomb it after they dropped it, and catch it before it hit, only to wash it in the water. I'm not sure what was going on, cause most of the time they would catch it in mid-air, but sometimes it would fall in the water, and they would retrieve it again. They all seeemd to be doing this, and they didn't seem to be stealing from one another. Fascinating to watch and shoot. 2 of 5

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