Trukhanova I.S. 2013. The Ladoga ringed seal (Pusa hispida ladogensis) under changing climatic conditions // Russian J. Theriol. Vol.12. No.1: 41–48 [in English].
Irina S. Trukhanova [irina_trukhanova@yahoo.com], Baltic Fund for Nature, Birzhevaya liniya 8, Saint-Petersburg 199034, Russia.
KEY WORDS: Ladoga ringed seal, climate change, ice conditions.
ABSTRACT. The Ladoga ringed seal is a Red listed subspecies of ringed seal, which most critical life cycle stages are closely related to ice presence on the lake. Climatic changes which are observed globally have their impact on local marine mammal populations resulting in shifts in distribution, abundance, migration pattern, disease occurrence, reproductive success. We considered trends in various ice related parameters on the Lake Ladoga since mid-XX century in relation to possible consequences to the Ladoga seal population. Analysis of the probability of winter with 100% ice coverage of the lake showed a statistically significant negative trend. Similarly, negative, though rather weak, trends were observed for sum of negative temperatures in the region and average ice thickness. The total duration of the ice period on the lake has reduced by 13.7% during the second part of the XX century. Maintenance of such trends, though non-significant on short term scale, can cause stress reactions in the Ladoga ringed seal living at the very southern edge of the species global range.