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For the northern Baltic region, Diplodia sapinea (Fr.) Fuckel, a well-known around the world pine pathogen, was first recorded in Estonia on Austrian pine ( Pinus nigra Arn.) in 2007. Wider monitoring of the fungus was promptly started. Shortly, in 2012, the native Scots pine ( P. sylvestris L.) was found symptomatic: first in Estonia, then in Latvia, and in 2013 in north-west Russia. Several individuals of exotic Mountain pine ( P. mugo Turra) and some Bosnian pines ( Pinus leucodermis Ant.) were also found to be infected. By the end of 2013, the front of the northward enlargement of the range of D. sapinea had reached to central Estonia. Early detection and continuous monitoring of this pathogen on native and introduced ornamental pine species will support forest and green belt management specialists with timely information, if an epidemic, as it occurred previously with the invasive Dothistroma needle blight, would emerge. [ABSTRACT FROM AUTHOR]

A Gyrodactylus parasite infected juveniles of brown trout (Salmo trutta L.) in a hatchery in Lake Janisjarvi, Russian Karelia. Molecular identification by ITS1-5.8S-ITS2 of ribosomal DNA indicated that the infection was caused by a non-segregating hybrid clone between unknown Gyrodactylus species and Gyrodactylus teuchis Lautraite, Blanc, Thiery, Daniel & Vigneulle, 1999, described from brown trout collected in France. The mitochondrial CO1 was sequenced from the hybrid, but it is not available from pure G. teuchis from type locality. The mitochondrial DNA was an independent clade among the wageneri group parasites, differing from the nearest relative G. derjavinoides by 19%. Morphometric measurements of the Janisjarvi parasite were compared with separate (host specific) G. salaris strains from farmed rainbow trout and salmon in Lake Onega, and with available data on G. teuchis from Western Europe, Austria and Poland. All isolates were distinguishable by morphometry, and the measurements are a useful primary diagnostic tool for the salmonid parasites in Karelian great lakes and fish farms. Pure G. teuchis is not found on Russian territory, and the other parent of the hybrid has not been discovered yet in any other country. A mini review of Gyrodactylus on salmonids in the Russian Karelia is presented. [ABSTRACT FROM AUTHOR]

The influence of the historical exploitiation and recovery of biological resources on populations of freshwater pearl mussel and salmon was studied in the Kozha river (Onega River Basin). The freshwater pearl mussel was characterized by a low population density (0.09 ind./m, on the average) and number of recruits. The role of the anthropogenic factor in the population is negligible; the effect of the pearl fishing is not observed. The dramatic decrease in the number of Atlantic salmon in the Onega River Basin in the late 20th century is a major reason for the slowed down reproduction of the freshwater pearl mussel. The second factor is the reconstruction of the Onega salmon hatchery in 1984, which led to a decrease in the juvenile salmon population density below the critical level on spawning and nursery grounds. As a result, mollusc reproduction has stopped. An artificial increase in the number of recruits must be developed in order to preserve the salmon population in the Onega River Basin. It is also necessary to forbid salmon fishing, including fishing migratory paths (with the exception of trapping for hatchery needs and traditional harvesting performed by locals in historical settlements). [ABSTRACT FROM AUTHOR]

North-west Russia, located between Ladoga and Onega Lakes and theBarents Sea, is remarkable for its high hydrological differentiation andabundance of water. The rivers and their tributaries are largely natural incharacter and with little disturbance by human activity. However, the situationis starting to change, so a biomonitoring approach has been developed to assessthe influence of land-use patterns on the structure of periphyton in thisregion. The periphyton communities in relatively pristine streams and in onesinfluenced by domestic sewage, agricultural, fish breeding farms, mineralisedmining mill wastes and other sources were analyzed in terms of speciesrichness,species diversity, species ecology values, biomass and chlorophyllconcentration. [ABSTRACT FROM AUTHOR]