Ladoga seal activities. The Ladoga seal is listed as an Appendix II species under the Bern Convention and also included in the Red Data Book of the Russian Federation. 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
Lake Ladoga Neva to the Svir. The basin of Lake Ladoga includes about 50,000 lakes and 3,500 rivers longer than 10 km. About 85% of the water inflow is due to tributaries, 13% is due to precipitation, and 2% is due to underground waters. Geologically, the Lake Ladoga depression is a graben and syncline structure of Proterozoic age (Precambrian). This "Ladoga–Pasha structure", as it known, hosts Jotnian sediments. During the Pleistocene glaciations the depression was partially stripped of its sedimentary rock fill by glacial overdeepening. During the Last Glacial Maximum, about 17,000 years BP, the lake served likely as a channel that