Variety and vulnerability of waterbird community in the eastern part of the Gulf of Finland in the zone of «Nordstream» marine gas pipeline

In frames of the monitoring of the "Nordstream" Project, in 2010-2013 the observations on the bird migrations and reproduction / nesting were carried out on the gas-pipeline corridor in the Russian sector of the Gulf of Finland (Baltic Sea). Migrations activity was studied in the coastal zone of Fiskar, Sommers, Nerva, Moschny, Seskar, Bolshoy and Maliy Tutters, and Gogland Islands and in Portovaja Bay on the northern coast of Gulf of Finland. Information about the nesting populations was collected during regular marshrout observations on these islands. It was found that the gas-pipeline construction did not effect the basic characteristics of functioning, dynamics and reproduction of the ornitocenosis in the Russian part of the Gulf of Finland. The disturbance factor was observed in the Portovaja Bay in form of decreasing of the number of nesting ducks. The rare and protected species of the ornitofauna are not affected by the pipeline construction. In the research area, the expansion of the cormorants and eiders was observed. It was shown that for the assessment of the pipeline influence on the ornitofauna only the species can be used which are ecologically connected with the water environment and the coastal zone biotopes. In this group there are the typical species of the marine Baltic fauna, and the species which are connected with freshwater lakes, but using the marine coastal zone as a place of relaxation and feeding during the migration period.