Environment

Uschkaniy Islands (origin: greenpeace)

The group of the Uschkaniy-Islands, formed by four islands, are part of the Barguzinskij National Reserve. Probably caused by their remote location far from the shore the islands are a place with the garanty to observe the endemic Baikal seals Nerpa. This is a species of fresh water seals. In former times, there have been some more summer resting places around the Lake Baikal, but recently only the Ushkanyi Islands remain in use by the seals. For the main part the seals´ diet consists of golomyanka, an endemic fish also called “fat fish”. Because of their position at the top of the food chain, the seals are a good indicator for the environmental quality of the lake. The seal population represents a bioaccumulator of persistent organic pollutants (e.g. DDTs, PCBs, CHLs, HCHs). Probably the accummulation of polluntants caused immunity against natural diseases but an increase of vulnerability for distemper-like disease. These diseases reduce the population extremely. In the 1950s the population was estimated to be about 20,000 - 25,000 seals. An increase followed in the 1960s, up to 35 to 40,000, which continued in the 1970s too. But in the winter of 1987-88 about 5,000-6,000 seals of an estimated number of 78,000-137,500 were killed by a disease caused by the phocine distemper virus. In the following years (1997 to 1999) diseases appeared repeatedly and reduced the population of seals. In addition, a number of hunting licenses from Buryat Ministry of Agriculture in Ulan-Ude were given in response to the strength of the population. For the year 2000 the Institute of Geochemistry at the Academy of Sciences in Irkutsk estimated the population size to 67,000 with an error of 12%.
The seals are threatened by illegal poaching and natural changes, for example the warming up of the lake which results in changes of the habitat conditions. Accidental capture in fishing nets, poorly concealed pups, orphans and death by sunstroke of older male seals might have reached 25,000 cases. The mortality is increasing.

(The endemic Baikal seals Nerpa (Phoca sibirica))

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