New habitat of alien crustacean species discovered by Russian scientists
During an expedition to reservoirs on the Volga river organised by the Papanin Institute of Inland Waters Biology, Russian scientists discovered a new habitat of an alien crustacean in the European part of Russia. Lobachevsky University was represented in the expedition team by Vyacheslav Zhikharev, Assistant of the Ecology Department at the Institute of Biology and Biomedicine. Together with Galina Shurganova, Professor of the UNN Ecology Department, and Artyom Sinev, Associate Professor of the Department of Zoology of Invertebrates of the Moscow State University, he co-authored an article on the discovery of this non-indigenous species that was published in the journal Invertebrate Zoology (Invertebrate Zoology, 2022, 19(3): 317-323).
"This species is quite rare in the European part of Russia; only a few finds of this species have been described. The location where this species was found is also unique: we discovered it at the mouth of the Shacha River, where warm waters of the Kostroma Power Station are discharged. Besides, this area appears to be a gathering place of many thermophilic species of living organisms. In addition to crustaceans, we also found some specimens of tropical plants and even thermophilic Asian molluscs of the Corbicula genus," said Vyacheslav Zhikharev.
According to the researchers, the main reason for finding such species in this area can be attributed to human activity. The alien crustacean Pleuroxus denticulatus was found in a tributary of the Volga, Russia's main waterway. There is an intensive flow of cargo through the Volga reservoirs, which contributes, along with a by-product of ballast water carried by the ships, to the dissemination of alien species.
"In our opinion, the estuary areas are some kind of buffer zones, or shelters for various species of living organisms where they can develop, occupy their biotopes and further penetrate into the Volga, dispersing downstream. The estuarial area of the Shacha River has favourable conditions, primarily temperature (the water area at the river mouth never freezes) and high biotopic heterogeneity - there are shoals, and there are areas with macrophytes (thickets of higher aquatic plants). It is an ideal place for the development of alien fauna. This is not the first find of non-indigenous species in the estuarine areas. In different tributaries of the Gorky, Cheboksary and Kuibyshev reservoirs we have already found more than 5 alien species. Most of them are thermophilic Asian species, but there are also some northern ones. The Volga is a transcontinental corridor for invasions, through which species spread both from north to south and from south to north," explained Vyacheslav Zhikharev.
During their following expeditions, scientists will continue to study the alien species discovered in this part of Russia. They will study its acclimatisation and naturalisation and will try to find out whether its numbers have changed and whether it has spread further into the Volga reservoirs. The work was carried out by researchers from the Aquatic Ecosystems Research Laboratory of the UNN Ecology Department, which was established as part of a consortium with the Papanin Institute of Inland Water Biology of the Russian Academy of Sciences to implement the Comfortable Environment Project as part of the Priority 2030 Strategic Academic Leadership Programme.