Instructions
Stand at the water's edge and observe the sand as the water recedes from the shore. Look for small holes in the sand.
Evaluate the hole to determine whether it was made by a clam. Clams can make round or keyhole depressions in the sand, or holes with raised edges that look like dimples.
Pound down on the sand next to the hole with your foot or a shovel. Notice whether water rises from the hole. If so, there is likely a clam under the surface.