The next stage of the walk from Hill End to Spaniard rocks saw an even greater reduction in the numbers of washed up starfish, and correspondingly greater concentrations of seashells in the strandlines, mostly empty shells of the bivalve Pharus legumen. The fine black detritus arranged itself in elaborate patterns mostly to do with the drainage of water back down the beach.
The sample of the fine dark particles that I took at the time, turns out to have a very interesting composition now I have had a chance to examine it under magnification back home. There is a fair proportion of small dark decaying wood fragments but most of the black material is composed of minute shiny hard particles of coal (what you might call coal dust). The coal is not difficult to account for since coal mining and its export from nearby docks was a major industry in the past. There are many ways the coal could have been accidentally deposited in the sea. Together with the coal dust there are various seeds that I am not able to identify and, most surprisingly of all, what seem to be myriads of delicate fish bones. In fact, so many small threadlike rib bones that the dried sample seemed to have a fibrous texture. Amazing.
Very interesting.
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Fascinating Jessica.
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Thanks, Adrian.
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Enjoying your odyssey!
It is fascinating just how different beaches can be. I am based on the south devon coast and I haven’t picked up a single example of Pharus legumen on the beaches that i frequent – yet commonly see the pod razor Ennis siliqua (? – from memory).
Also the sheer abundance of both the shells and the star fish is quite something.
…am working my way to part 8…
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I am pleased to hear that you are enjoying the beach walk with me! Thanks, Coleshed. I believe that Pharus was first described from Rhossili beach and I do not know what its current range is. Wasn’t there a mass stranding of starfish on a Devon beach last year? It is a wonder that there can be such enormous numbers of dead individuals and yet the community survives.
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