THE INVASION OF THE AMERICAN ROTIFER <i>KELLICOTTIA BOSTONIENSIS </i>(ROUSSELET, 1908) (ROTIFERA: BRACHIONIDAE) INto VYGOZERSKY RESERVOIR (REPUBLIC OF KARELIA)
The American rotifer Kellicottia bostoniensis (Rousselet, 1908) in the Vygozersky reservoir, which is still its most northern habitat in Russia, is found. The Vygozersky reservoir is located at 63° north latitude and refers to the White Sea catchment basin. It is a part of the White Sea-Baltic Channel (BBK). The first single individual of K. bostoniensis was noted in July 2007. In the summer of 2011 rotifers were found in the pelagic zone of almost all lake regions, but were absent in the littoral zone and in the reservoir inflows. Rotifers occurred in all areas of the reservoir in August 2017 and their number had grown up to 100-780 ind./m3. The number of aboriginal species Kellicottia longispina (Kellicott, 1879) was 5-76 times greater than that of invasive rotifers in dependence on conditions. The rotifer invasion into the Vygozersky reservoir could occur by bird migrations or water transport. The reservoir is a key area along the White Sea-Baltic span and migration routes. At the same time, the reservoir is a part of the BBK with active water transport traffic.