Friday, 5 June 2015

Pearl Mussels

This is an empty shell of a freshwater pearly mussel Margaritifera margaritifera.  This one is relatively small, but adults grow to be almost the size of a man's hand.  They used to be abundant in the streams of western Europe, from Norway to Spain, but the animal's extreme sensitivity to deteriorating water quality, loss of habitat, its dependence in its life-cycle on another declining group, salmon and trout, and human exploitation have driven it from many countries and close to extinction - hence its classification as an endangered species.  But while other endangered species can be brought into zoos and nurtured, the pearl mussel's complex life cycle means that, if it is to be saved from extinction, it has to be cared for in its native habitat.

Today, some 50% of the rivers in which there are self-supporting populations are in Scotland, yet over 90% of these have been damaged.  Unless more is done to preserve and protect the species, it is likely that it will be extinct within 25 years.

Many thanks, then, to Natalie Young of Pearls in Peril who came to Kilchoan Learning Centre last night to talk to interested people about the plight of the pearl mussel and to recruit us as 'Riverwatchers'.  Natalie described the importance of the pearls from these mussels in Scottish cultural history, and described an age in which pearl fishermen used to exploit the beds of mussels in such a way as not to damage them.  Sadly, today their greatest threat is from poachers, many of whom don't appreciate that only one in a thousand shells contains a pearl.

There was a full turnout for Natalie's talk - some 23 people present - as compared with her talk the previous night in Fort William, where two people attended.  And it's as well that there is so much interest in this area, as we have a number of local burns which are of grade A quality and contain beds of undisturbed mussels.  While Natalie hopes it will stay that way, she's appealing to everyone to watch out for signs of poaching, such as empty shells left on the banks of burns, and people working in rivers with glass-bottomed buckets and the characteristic split-ended stick used to pick up the mussels.  To take a mussel from the water is a criminal offence, so anything suspicious should be reported to the police.  And it was for this that she was recruiting the Riverwatchers - there are details of what they're asked to do here.

Photos taken in Ardnamurchan burns.

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