The number of salmonid taxa within some genera (e.g. Salmo, Salvelinus, and Coregonus) listed in various taxonomic databases (e.g. Fishbase or Eschmeyer's Catalog of Fishes) has increased very rapidly over the past 15-20 years. Many of these taxa are not widely accepted across the international community and are associated with very sparse data, leading to significant difficulty in accurately carrying out Red List assessments. The SSG strongly recommends a rigorous evaluation of the validity of these species designations, which can have real implications where legal protection is reflected by the use of these binomial taxonomic names.

Coregonus migratorius is endemic to Lake Baikal and its basins of tributary rivers within Russia and Mongolia. This species experienced a historic decline due to anthropogenic over fishing, but as a result of fish hatcheries on the Baikal Basin, the population is now considered stable. Lake Baikal itself is a UNESCO World Heritage site, which contains a protected Ramsar site. Ongoing threats to this species include habitat degradation and loss, resulting from deforestation that leads to sedimentation, reservoir construction and also pressures of poaching and possible over fishing. However, this species is considered both widespread and stable, occurring in a protected area with a successful conservation programme. Therefore, it is assessed as Least Concern.

This whitefish species is endemic to Lake Baikal and its basins of tributary rivers within Russia and Mongolia. From Baikal, it historically enters the Kichera, Upper Angara, Chivyrkuy, Barguzin, Selenga and other rivers for spawning. From the Selenga, it enters the Chikoy and Orkhon. It does not enter the Lower Angara for spawning, although cases of the presence the species in the Angara have been reported.

Overall, there are four subpopulations of Coregonus migratorius in Baikal: the North Baikal, the Chivyrkui, the Selenginsk and the Posol’skiy subpopulations (Popov 2007, Voronova et al. 2015).
This is the main commercial fish of Lake Baikal and historically it underwent a dramatic decline from fishing pressures. However, thanks to ongoing fish hatcheries on the Baikal Basin being able to compensate for the negative impact on fish resources, this species is now common and considered relatively stable within the lake (Voronova et al. 2015). The scale of works on artificial reproduction of the Baikal Omul is unparalleled in the world, with over 50 billion ex. larvae and 280 million ex. young omulas produced in Lake Baikal (Voronova et al. 2015).

There are four subpopulations of this species in Baikal: North Baikal, Chivyrkui, Selenginsk and Posol’skiy subpopulations. They differ from each other in the number of gill filaments (Popov 2007, Voronova et al. 2015). Biotopically, three morpho-ecological groups (subpopulations) of omul are distinguished: pelagic, coastal and bottom-deep-water (Popov 2007, Voronova et al. 2015).

In general, omul spends winter in the bottom layer of water at a depth of 100-300 m and leads an active lifestyle, eating and migrating along the lake. In June, the omul leaves the coastal shallow waters for feeding. By mid July, when the spring regime of Lake Baikal is replaced by summer regime and the development of zooplankton reaches its maximum, the omul moves from the coastal zone to more open areas of the lake (Popov 2007, Voronova et al. 2015). By the same time, shoals of sexually mature individuals are formed. 

The Baikal Omul is characterized not only by horizontal but also vertical migrations due to the seasonal nature of distribution and migration in the water column of zooplankton organisms. The Baikal Omul inhabiting the coastal zone becomes sexually mature for the first time in 4+ - 6+ years, in mass in 6+ - 7+ after reaching 25 cm length; whereas the omul that leads a predominantly benthic-deepwater lifestyle, matures much later, at 11+ - 15+ with a length of 34-52 cm (Popov 2007, Voronova et al. 2015).

The spawning grounds of the Baikal Omul are located at different distances from river mouths: in Kichera - 70 km, in the Upper Angara - 250 km, in Bolshoy Chivyrkui and other small rivers - 10-15 km (Popov 2007, Voronova et al. 2015). In Selenga, the omul enters the spawning season in favourable hydrological conditions at a distance of 153 km, and there is information about the rise of the omul from Baikal to spawning and in the upper Selenga (Popov 2007, Voronova et al. 2015). Spawning of the omul takes place in the second half of October at the starting water temperature of 4 ºC and optimal 1 ºC and below, on the river sections with stony-pebble substrates and moderately fast flow (Popov 2007, Voronova et al. 2015). As a rule, mass spawning almost coincides with freeze-up on rivers and is usually observed during the night. The development of fertilised eggs lasts 180-210 days until April-May (Popov 2007, Voronova et al. 2015). Hatched larvae are passively carried away to Baikal by the current.

An important role is played by the activity of fish breeding plants located on Lake Baikal (Bolsherechechensky, Selenginsky and Barguzinsky) in maintaining the number of omul in the lake itself (Popov 2007, Voronova et al. 2015). Thus, for many years, the reproduction of the populations of the bottom-deep-water omul of the Posol’skiy Bay has been done only artificially (Popov 2007, Voronova et al. 2015).

The Baikal fisheries basin includes water bodies of the Irkutsk Region, the Republic of Buryatia and the Trans-Baikal Territory. These areas face increased anthropogenic impacts of deforestation, pollution of spawning rivers, and destruction of natural spawning grounds, causing the ecological situation in the places of fish spawning and wintering to deteriorate, reducing efficiency of natural reproduction (Voronova et al. 2015). This area is also under threat from poaching and increased uncontrolled fishing pressure (Voronova et al. 2015). Also, the creation of the Angara Reservoir Cascade (Irkutsk, Bratsk, Ust-Ilimsk) has disrupted the natural reproduction of fish. Filling the Boguchansky reservoir, the fourth on the Angara River, will further worsen the situation (Voronova et al. 2015).

This is the main commercial fish of Lake Baikal (Popov 2007, Voronova et al. 2015). Historically this species was over fished, but with successful fish hatcheries constructed in the Baikal Basin, three of which are still operating, this species has recovered and is stable under the rising anthropogenic fishing pressures (Voronova et al. 2015).

Compensating for the negative impact on fish resources, five fish hatcheries were constructed in the Baikal Basin, three of which are still operating (Voronova et al. 2015). The scale of works on artificial reproduction of the Baikal Omul is unparalleled in the world, with over 50 billion ex. larvae and 280 million ex. young omulas produced in Lake Baikal (Voronova et al. 2015). As the main result of this activity it can be considered the relative stability of this species stocks in the last decades against the background of the increasing anthropogenic impact on the ecosystem of the lake (Voronova et al. 2015). Within the World Natural Heritage Site of Baikal lake, the range includes the boundaries of the Ramsar site Selenga Delta. Continued monitoring of this species harvest and population is recommended.