Freshwater Pearl Mussel and Elephants

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Fifteen years ago practically no one had heard of Freshwater Pearl Mussels and now mainly due to road schemes everyone has heard of these molluscs which are Irelands oldest living species living til they are up to 130 years old. For thousands of years these mussels have been quietly filtering river water and living side by side with us humans.

Large black FreshwaterPearl Mussels  grow to 15cm in size and  live in gravel of clean rivers. It is easy to age them as they have growth rings on their shells similar to growth rings of trees. They occasionally produce a pearl and this has been one of the main reasons that populations of these animals have gone extinct throughout the world. Many populations have been stripped out in the search for rare pearls.  They are considered to be living extinct species by some experts because there are no young in many of their populations.

This is no surprise ….We are living in the great age of extinctions. Our planet is now in the midst of a massive extinction of plants and animals. We’re currently experiencing the worst rate of species die-offs since the loss of the dinosaurs 65 million years ago.

A recent report by the World Wildlife Fund (WWF) estimates that by 2020 populations of vertebrates (animals with a backbone) will have fallen  by 67% since 1970. Extinction rates are now running at 100 times their natural level because of deforestation, hunting, pollution, overfishing and climate change.

Some people think that conservationists seek a landscape without man, but nothing could be further from the truth. Over thousands of years animals, particularly birds, have adapted to the cycles of farming. We manage the landscape for many of these species,

However, with the common agricultural policy we have had massive changes in farming since we joined the EU in 1973. The birds simply couldn’t keep up and are now at the lowest levels since records began across Europe, including  Ireland. Their numbers have reduced by almost half, down from 600 million in 1980 to just 303 million today

Corn Bunting, once abundant in Connemara, has declined by 66% across Europe, and is now extinct in Ireland. The iconic bird of hay meadows the Corncrake have less than 200 singing males left in Ireland  and the Barn Owl is down to 300 pairs. The Curlew, with its characteristic cry has less than 200 pairs breeding in Ireland and could be next to go extinct in Ireland.

Freshwater species are faring even worse than farmland birds, with declines of 81 per cent between 1970 and 2012. Here in the west we have (had?) the best salmon rivers in Europe. Sadly our  stocks of wild Atlantic salmon have declined by over 60% in 40 years and at the Ballina Salmon festival it is difficult to get wild salmon to eat now only farmed salmon is plentiful. I need not talk about the complete collapse of sea trout stocks. These trends are  the same the world over….be it elephants, tigers or monkeys.


The Freshwater Pearl Mussel gets bad press. All that is needed to protect them  are  clean waterways in near natural state. They have an interesting lifecycle. The mussels release young to the water in May June and the young mussel attaches to a salmon it spends a year on the gills of the salmon before dropping off a year later and burying itself in the river gravels.  They are very sensitive to small amounts of sediments in the water as sediment uses up the oxygen available and the young mussels buried in the sediment die.

Republic of Ireland has an estimated 12 million individuals, or approximately 46% of the EU population. Two million of these are in the river at Oughterard. Thus the Owenriff River falls into the rare category of being one of the few remaining breeding populations in the EU and the world. However, its population is in decline,  two pollution incidents in the last 12 years have had a detrimental impact on this population.  Don’t  let the high numbers  deceive you. Most of the mussels here are old; there are not enough young mussels to sustain the population.

This pattern is being repeated the country over with the majority of mussel populations failing to recruit young mussels over the last 30 year period, and widespread extinction of mussel populations is predicted if water quality dosn’t improve.


It is not a case of road widening or Freshwater Pearl Mussels; we can have both. We are sophisticated enough now to carry out bridge and road works and protect water quality too. It means though that written words have to be translated into actions while works are being undertaken  and real steps taken to protect these sensitive aquatic ecosystems.

We would not want a planet devoid of wild animals and plants. Yes in that very sentence there is an inherent responsibility to protect our fellow passengers on the earth. It must be viewed locally …we cannot really help the elephants the lions and the tigers. We can however do our bit to protect nature on our doorstep. It would be to our shame if we allowed these rare species go extinct in the connemara wilderness  on our watch.


Marie-Louise HeffernanFreshwater Pearl Mussel and Elephants

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