In the lower reaches of the Kem River in the north of Karelia, biologists have discovered a European pearl herring population. Previously it was believed that it completely disappeared in these places in the last century because of uncontrolled extraction of pearls, timber floating and the construction of a cascade of Kemsky HPP.
Victor Mironov, the author of findings, the leading biologist of the Institute of Biology of the Karelian Research Center of the Russian Academy of Sciences:
– Contemporary mollusk finds have been made on rapids of the river, which have not yet been affected by the construction of hydroelectric power stations. I found the live shellfish and its shell in the Lepostrov district in Kemi, and a few more shells were passed to me by the locals. The collected material was handed over to colleagues-hydrobiologists. They confirmed that the findings belong to the European pearl mussel.
– The presence of not only shells, but also living specimens suggests that the pearl herring population is recovering. But any conclusions can be drawn only after a full study of the river with the use of diving equipment. We are going to hold it next year, – the research fellow of the Institute of Biology, PhD Denis Efremov believes.
Now the lower part of the river Kem remained the last unregulated (that is, natural) site, salmon fish are still spawning here. It is with them that biologists associate the revival of the pearl mussel.
Evgeny Ieshko, Ph.D., the laboratory of parasitology of plants and animals of the IS KarRC RAS:
– The fact is that in its life cycle there is a larval stage, leading a parasitic way of life, – says Doctor of Biological Sciences Evgeny Ieshko. – Microscopic larvae settle in the gills exclusively salmon and trout, practically without harming them. After maturing, they come out into the environment and eventually become mollusks. Therefore, the existence of a pearl is possible only where salmonid fish go. The creation of artificial barriers to these fish is one of the causes of death of the pearl mussel populations.
Once the pearls were produced on a large scale on many rivers in the basin of the White Sea. About its former meaning resembles a ring of pearls on the modern coat of arms of Kemi. Ornaments from river pearls were worn by Russian tsars and metropolitans, he went for export: only in 1912 the treasury gained from his sale 300 thousand rubles in gold. Now the pearls are included in the Red Book of Russia and the Red Book of Karelia, its current state causes serious concern among scientists around the world.
The lower course of the Kem River is one of the last known pearl herring habitats in Karelia. And it is there that in the near future they plan to build the Marine Hydroelectric Power Plant. In autumn of this year, honorable citizens of Kemi have already applied to Karelian governor Artur Parfenchikov with a demand to abandon the plans for erecting a hydroelectric power station. In this case, the authors of the appeal believe, the ancient Lepostrov will be flooded, where the historical monuments of Kemi are – the Assumption Cathedral and the Trinity Chapel, and the city’s ecology will be damaged.
Artur Parfenchikov quickly reacted to these claims. He promised that the Maritime HPP will be built only in the absence of a negative impact on the city’s historic sites, on the environment, but with a real positive impact on the economic situation. I wonder if the governor will consider the opinion of biologists who are concerned about the fate of the Red Book species of the pearl, and will it consider it necessary to preserve the ancient symbol of Kemi – the river pearl?
Source – https://primapearl.ru/