New data on distribution of spring and autumn haul-out sites of the Baltic ringed seals (Pusa hispida botnica) in the Gulf of Finland
The Baltic ringed seal represents a separate population in the Gulf of Finland, inhabiting mainly the easternmost part of the Gulf. Population number decreased considerably during 20th century. At present time it amounts to approximately 100–300 individuals. Seasonal distribution of the ringed seal is still poorly studied, particularly, distribution of molting and resting haul-outs in spring and autumn. In this work, an inventory list of haul-out sites is provided based on local people poll data, personal observations, and published literature. The inventory includes 66 haul-out sites. Modern status of haul-outs in nine areas of eastern part of the Gulf, seasonal dynamics, and long-term changes in the using are considered. The most abundant aggregations of ringed seal form in the area of Kurgalskii Reserve while the highest number of haul-out sites was registered in the area of Berezovyi Archipelago and Vyborg Bay. It seems possible that there are two separately used systems of haul-out sites resulting from distribution of coastal biotope complexes (stony ridges and banks) within the population area and distribution of ringed seal individuals during preceding breeding season. Refs 47. Figs 3. Table 1. App. 2.
Baltic ringed seal, seasonal distribution, spring and summer haul-out site, rookery, Gulf of Finland
Articles of Biological Communications are open access distributed under the terms of the License Agreement with Saint Petersburg State University, which permits to the authors unrestricted distribution and self-archiving free of charge.