The Baikal ichthyofauna has formed as a result of the fishes of several fresh water complexes coming to the lake. All the fishes can be divided into several groups in accordance with their origin and the living conditions:

The Baikal invertebrates are:

Baikal Seal - Nerpa (Phoca sibirica)
This is the only mammal of Baikal and the only landlocked seal in the world. Unlike other seals, it lives all year round in or near fresh water and never enters the ocean to breed or migrate.
As some of the world`s smallest seals, Baikal Seal reach a nose-to-tail length of only about 1.3 m and weigh 80 to 90 kg. Adults are silvery gray with yellowish gray bellies. Females are slightly lighter and shorter than males. Baikal seals can live over 50 years, considerably longer than the 20-year life span of most seals.

Brown bears (Ursus arctos)
The largest populations of brown bears in the world live in Siberian Taiga forest.
Bears generally weight 200-300 kilos. A bear entering hibernation weights 60% more than it did a few months earlier. In late autumn they retire to their winter den. Bears are not true hibernators and may be aroused easily without too much difficulty. However, their heart beat, breathing rate, and temperature are depressed. This slowdown of body functions will help to conserve the stores of fat. Bears leave their den by mid April or early May. A female bear may give birth to cubs in late January. The cubs stay with their mother through the summer and then share the den in the following winter. Mother and father have full charge of the young. The bear is territorial by nature and each bear has its own area that it uses and protects.

Sable (Martes zibellina)
Sables are actually marten - the finest, most luxurious and expensive marten. The best sable comes from the Barguzin Valley Sables range in color from tan to black, black being the most prized. The top grade of black sable fur is called "black diamond". It is not very easy to see a sable in the taiga. The sable is a very careful and extremely secretive predator. Sable hunting requires special hunting skills, endurance and also good knowledge of the animal's habits and habitat.

Gray Wolf (Canis lupus)
The Wolf is a member of the dog family. These animals are divided into packs which are believed to be a family group. Each mated pair produces a litter of about 5-6 pups in May. Wolves are highly social by nature. Each pack is well-organized and has its most dominant and submissive family member. Research has shown that a wolf is not a reckless killer of wild life and therefore its prey is mostly old and sick animals. Wolves are stimulated to chase any animals that will run from them.

Big Cormorant (Phalacrocorax carbo)
The big cormorant is a representative of the cormorant’s family. They live near water in big colonies. It catches fish diving under the water. In the past the cormorants were among the most numerous birds by the Baikal. Not for nothing three Baikal islands are named the Baklany (Cormorants). Nowadays it is in the category of the species which are practically extinct. By the end of the 40`s of the 20th century the quantity of the big cormorants at the lake had decreased greatly. Many places of the cormorant`s settlings were flooded because of the water level raise caused by the construction of the Irkutsk hydro power station. The cormorants feed on fish and many fishermen blamed them of valuable fish species disappearance, so the birds were hunted, their eggs were collected in the colonies, the young were killed and the adult birds were shot.

Bustard (Otis tarda)
The bustard is one of the biggest and valuable birds of our country. It can weigh up to 16 kg. It can be distinguished from other birds by its big size, strong legs and multi-coloured feathers. It lives in the steppe and forest-steppe regions. It is a bird of passage, it flies for Mongolia and China for winter. It comes back in April-May and leaves in September-October. The flight of the bird is light and swift, but it takes off heavily, with a running start.
It is a very cautious bird, with good eyesight. It builds its nests on the ground digging a hole and lays 2-3 eggs. The bustard feeds on young grass sprouts, wild and cultivated cereals, insects, rodents, lizards and frogs.

Steppe Eagle (Aquila nipalensis)
In the Baikal land 7 species of eagles and sea eagles live: the golden eagle, the steppe eagle, the dwarf eagle, the white-tailed sea eagle, the long-tailed sea eagle and others. There is no such diversity of eagles anywhere else in Northern Asia. The Aquila heliaca Savigny eagle is considered to be one of the most beautiful and magnificent birds of prey. It is the real natural prototype of the legendary "bald eagle". The wing-spread of it is 2 m. This eagle lives only on the Olkhon Island and in its neighbourhood.

White-Tailed Eagle (Haliaeetus albicilla)
This eagle live in the coastal landscapes all over the territory of Russia with the exception of the tundra on the Arctic coast including the Kola Peninsula and the Anadyr basin, but it is extremely rare there. The nesting places are sea coasts, big rivers valleys, lake coasts and islands. They are connected with the presence of big trees with thick trunks appropriate for nesting. The second necessary condition is a lake abundant in game. In the treeless landscapes it can nest on rocks. They start reproduction at the age of 5 or 6; the couples remain throughout their whole lives (about 20 years). They have got permanent nesting and hunting places.

Swan (Cygnus)
The swan is one of the biggest birds of Buryatia. It weighs 7-10 kg and it is up to 150-180 cm long. The wing is 56-63 cm long. They live in shallow waters, for the neck is long enough to get the food from the bottom. The feathers are splendid and snow-white. It is called the "calling" swan because of its loud, blaring voice. It is a beautiful, proud and magnificent bird.