Seashells in situ on Swansea Bay strandlines or drift lines are mostly tiny immature common cockle shells but there are many other species of bivalve and gastropod mollusc shells too. I noticed mussels, tellins, and oysters, winkles, top shells, netted whelks, sting winkles, slipper and common limpets, and I am sure there were many more types. There were seven drift lines of shells lying parallel to the water line and decreasing in the number of accumulated shells sequentially up the shore. Each line represents the highest reach of the sea on a series of subsequent falling tides that were decreasing in reach each time.
It was interesting to see that wave-worn pieces of black coal and dark clinker from industrial plants across the bay were scattered amongst the light coloured shells together with a fair number of burial-blackened periwinkles. Many of the shells were fragmented and the accumulations included the calcareous tubes of marine worms. It would be lovely next time to take a sample home and sort it through under a binoc. I am sure that it would reveal much more information.
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Some of the things that caught my eye as I walked along the beach at Studland in Dorset, England, included interesting beach stones; stranded clumps of red, green, and brown seaweeds; an empty shell of a clam just eaten by a bird; and tubes of Sand Mason Worms.
The shingle shore at Whitstable in Kent is protected by massive wooden groynes or breakwaters. At the time of my visit, the tide was high and the flint and other mostly worm-holed pebbles were steeply banked. The flat top of the beach was stabilised by vegetation with pink and white valerian and yellow ragwort the most colourful flowers. Pale bands of white empty oyster shells (mostly the rock oyster Crassostrea gigas) were high, dry, and dull on the shingle between the groynes; while lower down splashed by waves or heaped up against the wooden sea defence structures was a great variety of other empty shells including winkles, cockles, mussels, limpets, slipper limpets, whelks, netted whelks, Manila clams, and sting winkles. These were jumbled up with wet and dry seaweed, horn wrack, small pieces of driftwood, and flotsam. There was a marked contrast in the appearance of the shells and stones between the water’s edge where the wet shells were brighter and more colourful and the upper shore where everything was dry.