beach stuff

Monday was so much fun. It was foggy so it was hard to see the rafts of ducks out on the oceans. Instead we looked at our feet. Here is a small collection of beach stuff we saw. The tiny shell in the top middle is a dwarf surf clam. I was told that Red Knots eat these. There were Red Knots present. But I do not know what this is in Hallie's hand. Can anyone tell me? Thanks