Lake Baikal, in southern Siberia in Russia, is a rift lake formed 25−30 million years ago and is the world’s deepest lake, holding 20% of the world’s fresh water. Its catchment area contains substantial biodiversity with more than half of its species being endemic (Garmaeva, 2001). An endemic, freshwater seal (Phoca sibirica) lives in the lake. When its numbers dramatically declined between 1997 and 1999, hunting was blamed, but studies suggest that the Lake Baikal seal may be more susceptible to heavy metal toxicity than other aquatic mammals (Watanabe et al., 1998). To protect the lake and its unique biodiversity, 8.8 million hectares including the lake and its surrounding area were designated as a UNESCO World Natural Heritage Site in 1996.
Over 360 rivers and streams flow into the lake while only one river, the Angara River, flows out. Sixty percent of the inflow of water arrives through the Selenga River. The waters of Lake Baikal are generally clear with Secchi depths of at least 20 m (Hampton et al., 2008) but as low as 1−2 m in some shallow areas (Kozhova and Izmest'eva, 1998). Summer surface water temperature ranges between 12 and 14 oC but climate change has been warming these waters at an average rate of approximately 0.20 oC/decade (Hampton et al., 2008). Waters are well oxygenated throughout the water column (Kozhova and Silow, 1998).
Fish and Fisheries
There are 56 species of fish from 14 families in the lake; 27 from the Cottoidae family are endemic and found at all depths (Kozhova and Izmest'eva, 1998). The endemic omul (Coregonus autumnalis migratorius) is a planktivorous arctic whitefish that accounts for two thirds of the annual commercial catch (Garmaeva, 2001). During the 1940−50s, omul abundance declined and a subsequent ban on omul commercial fishing helped increase their abundance although it has not returned to historic levels (Kozhova and Silow, 1998). Other important fish species include two littoral predators, the Siberian taimen (Hucho taimen) and the lenok (Brachymstax lenok) (Matveyev et al., 1998), whose populations, along with the omul, are thought to be declining due to hydroelectric dams, logging, overfishing, and pollution that impacts spawning and nursery habitat (Kozhova and Silow, 1998).
In Lake Baikal, there are 15 commercially exploited fish species and over 50 registered commercial fishing enterprises (Brunello et al., 2004). Recreational fishing and ice-fishing are unrestricted across the lake. Species sought by anglers include black grayling (Thymallus arcticus baicalensis) European perch (Perca fluviatilis) omul, pike (Esox lucius), bullhead (32 Ictalurus spp.) and sturgeon (Acipencer schrenskii and A. baeri baicalensis). In Mongolia, the taimen, a solely freshwater salmonid that reaches lengths in excess of 2 m and weighs up to 95 kg (Matveyev et al., 1998), is the target of anglers in the Selenga River and its tributaries. Taimen populations here have been in decline due to loss of spawning habitat, declining water quality, and overfishing (Matveyev et al., 1998).
Population Growth and the Economy
The human population in the catchment is low, approximately 2.5 million people, but steadily increasing (Kozhova and Silow, 1998). The heaviest population density occurs in the southern part of the watershed where 60−70% of the population resides (Kozhova and Silow, 1998).
The Russian GDP per capita is $4,000 and $2,200 in Mongolia (Brunello et al., 2004). Fisheries do not play a significant role in the GDP of either country. Buryatia, in south-central Siberia, occupies over 60% of Lake Baikal’s shoreline, is an important agricultural area, and possesses large deposits of minerals, making mining a growing industry which could have negative ecological impacts on the watershed in the future. Although fishing plays only a minor role in the local economy, the lake has been drawing increasing tourism dollars to the region. Three hotels built in Irkutsk created 570 jobs while over 167,000 tourists visited Buryatia in 2003, bringing an estimated 298 million rubles (over $9 million US) to the region (Baikal Economic Forum, 2008; Ministry of Economy Development (of the Republic of Buryatia), 2006).