Ladoga seal Ladoga seal The Ladoga ringed seal (; Pusa hispida ladogensis), is a freshwater subspecies of the ringed seal ("Pusa hispida") which are found entirely in Lake Ladoga in northwestern Russia. The subspecies evolved during the last ice age, about 11,000 years ago. As the glaciers retreated and water levels changed, the Baltic ringed seal (including Ladoga seals) was trapped in freshwater lakes and separated from the Arctic ringed seal. It is related to the even smaller population of Saimaa ringed seals in Lake Saimaa, a lake that flows into Ladoga through the Vuoksi River. The adult Ladoga seal grows to
Staraya Ladoga his successor Oleg. The Heimskringla and other Norse sources mention that in the late 990s Eric Haakonsson of Norway raided the coast and set the town ablaze. Ladoga was the most important trading center in Eastern Europe from about 800 to 900 CE, and it is estimated that between 90% to 95% of all Arab dirhams found in Sweden passed through Ladoga. Ladoga's next mention in chronicles is dated 1019, when Ingigerd of Sweden married Yaroslav of Novgorod. Under the terms of their marriage settlement, Yaroslav ceded Ladoga to his wife, who appointed her father's cousin, the Swedish earl Ragnvald