Welcome to the Shell Beach Counting Confabulation!
Technical material and data are at the end of the page, so those who just want to look at pictures may do so. Navigation buttons are at bottom of page.
Shell Beach looking in the northwest in the direction of Hamelin Pool and the mainland (not visible). Petit Point (upper left) divides the Haaridon Bight (Shell Beach is at its southern end) from Hamelin Pool to the north and west.

This beach is part of a 110 kilometer long by about 10 meter deep deposit of teeny shells. The visible beach is about 80 meters from damp sand to the top of the shell berm. There are roughly 1100 m x 10 m x 80 m or 880,000 cubic meters of shells.

And, for the insatiably curious, the rough calculation is that
880,000 cubic meters divided by 1.6 x 10^-8 cubic meters per half shell = 5.5 x 10^13 half shells or 55 trillion half clams. To trim things down a bit, that is a mere 27.5 trillion clams, mostly of one species. The beach is not an exact sample of the ecosystem of the Bight, because not all its species are easily dislodged and cast ashore. However, the beach deposit of shells indicates lack of diversity, which is often found in environments where conditions are hostile to all but a few species.

Note the water color and sky do not match. That is because the salinity is high enough for the dissolved salts to be prominent in greening color of the sea water. I was informed that the wind generally blows in toward this beach, as it was doing on our visit. The water at Shell Beach, like the water at the Hamelin Pool is warm, high in salts, low in nutrients and lacks sediment input (fertiliztion) from a river or stream.

Sorting the shells in a sample. The shells were nearly all Fragum erugatum with a few turbans, periwinkles and a slender clam mixed in. The mean size of a shell turned out to be close to 10 millimeters. For calculation convenience, we assumed each shell to occupy a space 2 mm x 10mm x 8 mm because they nested inside each other (sort of). This gives each half shell approximately 160 cubic millimeters of volume to occupy, or 0.000000016 cubic meter. Click on the image to view it full size.
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