Leningrad Oblast of two great lakes of the European Part of Russia, Lake Ladoga and Lake Onega. Its northeastern part, between the Gulf of Finland and Lake Ladoga, occupies the Karelian Isthmus. Some islands in the Gulf of Finland (including Kotlin, on which the city of Kronstadt has been built) and Lake Ladoga (including Konevets) also belong to the oblast. Much of the area of the oblast belongs to the drainage basin of the Neva, which is the only outflow of Lake Ladoga. Whereas the Neva, which flows to the Gulf of Finland (the city of Saint Petersburg is located in its
Ladoga seal five, and males at the age of six to seven. Pups are delivered in February through March, with weaning taking place after six to eight weeks. A normal lifespan is about 30–35 years. The current population is about 2,000–3,000, down from approximately 20,000 at the beginning of the 20th century, due to overhunting; hunting of the seals was banned entirely in 1980, but some illegal poaching still occurs. The species' primary threats include entanglement in fisheries netting, industrialization in the areas surrounding Lake Ladoga, fuel spills from water vessels and the disturbance of their warm-weather sunning places by human recreational