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Wildlife

The Ladoga is rich with fish. 48 forms (species and infra specific taxa) of fish have been encountered in the lake, including roach, carp bream, zander, European perch, ruffe, endemic variety of smelt, two varieties of Coregonus albula (vendace), eight varieties of Coregonus lavaretus, a number of other Salmonidae as well as, albeit rarely, endangered Atlantic sturgeon (formerly confused with European sea sturgeon). Commercial fishing was once a major industry but has been hurt by overfishing. After the war, between 1945 and 1954, the total annual catch increased and reached a maximum of 4,900 tonnes. However, unbalanced fishery led to the drastic decrease of catch in 1955–1963, sometimes to 1,600 tonnes per year. Trawling has been forbidden in Lake Ladoga since 1956 and some other restrictions were imposed. The situation gradually recovered, and in 1971–1990 the catch ranged between 4,900 and 6,900 tonnes per year, about the same level as the total catch in 1938. Fish farms and recreational fishing are developing.

It has its own endemic ringed seal subspecies known as the Ladoga seal.

Since the beginning of the 1960s Ladoga has become considerably eutrophicated.

Nizhnesvirsky Natural Reserve is situated along the shore of Lake Ladoga immediately to the north of the mouth of the River Svir.

The Ladoga has a population of Arctic char that is genetically close to the chars of Lake Sommen and Lake Vättern in southern Sweden.