From Irkutsk, April 9th 2009
- The big golomianka: Comephorus baicalensis (Pallas, 1776), where the female can reach 25cm and the male 16cm.
- The small golomianka: Comephorus dybowskii (Korotneff, 1905), where female and male can reach respectively 15 and 12cm.
Golomianka has a white transparent body with pale pink shadows, nacre reflects that makes the orange around the eyes come out even more. The legend says that it is possible to read the newspaper through it. Its wings are indeed fully transparent.
This fish contains a lot of fat. In the big golomianka, fat represents 43 to 44% of its total weight (Galazi, 1984). But its main specificity is its reproduction modus. Different to all fishes of Baikal and almost all fishes on Earth, the golomianka is viviparous. It gives birth to “larves” that can live on their own, and not to eggs. It therefore does not need to move to give birth, neither within the lake, nor in the rivers. The other specificity is that parents die after giving birth. The golomianka is the only fish on Earth to associate viviparous reproduction modus to death after giving birth.
An interesting study has been led to classify the nierpa within the existing Phoca families and uses 3 different methodologies. The objective was to prove that it comes from Phoca hispida, the ring Arctic “phoque”, called “akiba” by Russians, who would have migrated through Ienissei and Angara rivers system. Once settled in the lake, it would have evolved progressively to match its new geographical context and reach its current morphology.
Method 1: comparing morphology
The “griffes” of nierpa are bigger and stronger because the ice of the lake is more solid than the one of the sea. The positions and structure of its teeth with more space in between correspond to an alimentation with smaller fishes. The larger eyes and higher haemoglobin level in its blood are designed for deeper waters to find their favourite food.
Method 2: comparing parasites
The parasites on the nierpa (in French, “vers parasites et pous”) and the ones on the Phoca hispida have many similarities, while they are totally different from the ones on the Phoca caspica for example (Pasthoukov, 1982, 1993).
Method 3: using genetic tests
Unfortunately, the more recent genetic method does not allow confirming the classification confirmed by methods 1 and 2. The genetic similarity within the Phoca family is at 55% between the 4 sub-families, taken two by two. Therefore, the similarity between nierpa and Phoca hispida are not stronger than with other Phoca sub-families, and does not lead to a clear classification.
Baikal Lake is connected to the Arctic Ocean by one river, that’s why its endemic species can be divided in two groups: indigenous species and species coming from Arctic Ocean. These species are classified as "least concern" by IUCN and therefore not endangered, but are scientifically very interesting to study.
1. Indigenous species
1.1 The endemic reliques
Some species, known from the Tertiary and shared with other lakes, have disappeared elsewhere and only remain in Baikal. The best example is the sponges (“goubki” in Russian), attached to the rocky deep ground of Baikal until 600m depth. They belong to a family unique in the world: Lubomirskiidae, which are key information database as they have almost not evolved since the Tertiary. Scientists call them “living fossils”.
1. Indigenous species
1.1 The endemic reliques
Some species, known from the Tertiary and shared with other lakes, have disappeared elsewhere and only remain in Baikal. The best example is the sponges (“goubki” in Russian), attached to the rocky deep ground of Baikal until 600m depth. They belong to a family unique in the world: Lubomirskiidae, which are key information database as they have almost not evolved since the Tertiary. Scientists call them “living fossils”.
1.2 The Baikal monsters
Other species have an enigmatic origin. We can say that they were born in Baikal and have evolved locally. It is the case of the fish without scales (see below picture).
But the most surprising ones are the so called “naked fishes”:Other species have an enigmatic origin. We can say that they were born in Baikal and have evolved locally. It is the case of the fish without scales (see below picture).
- The big golomianka: Comephorus baicalensis (Pallas, 1776), where the female can reach 25cm and the male 16cm.
- The small golomianka: Comephorus dybowskii (Korotneff, 1905), where female and male can reach respectively 15 and 12cm.
Golomianka has a white transparent body with pale pink shadows, nacre reflects that makes the orange around the eyes come out even more. The legend says that it is possible to read the newspaper through it. Its wings are indeed fully transparent.
This fish contains a lot of fat. In the big golomianka, fat represents 43 to 44% of its total weight (Galazi, 1984). But its main specificity is its reproduction modus. Different to all fishes of Baikal and almost all fishes on Earth, the golomianka is viviparous. It gives birth to “larves” that can live on their own, and not to eggs. It therefore does not need to move to give birth, neither within the lake, nor in the rivers. The other specificity is that parents die after giving birth. The golomianka is the only fish on Earth to associate viviparous reproduction modus to death after giving birth.
2. Species coming from Arctic Ocean
Other species come from a migration from Arctic Ocean and an evolution in situ. It is the case of the most appreciated fish of the lake, the “Omul”, Coregonus autumnalis migratoris (Georgi, 1775) that most probably migrated from the Arctic Ocean via Ienissei and Angare rivers. It is also the case of the “phoque”, the nierpa, Phoca (Pusa) sibirica (Gmelin, 1735), one of three fresh water “phoques” on Earth with the ones from Ladoga and Saimaa lakes but the only one to live so far from the sea.An interesting study has been led to classify the nierpa within the existing Phoca families and uses 3 different methodologies. The objective was to prove that it comes from Phoca hispida, the ring Arctic “phoque”, called “akiba” by Russians, who would have migrated through Ienissei and Angara rivers system. Once settled in the lake, it would have evolved progressively to match its new geographical context and reach its current morphology.Method 1: comparing morphology
The “griffes” of nierpa are bigger and stronger because the ice of the lake is more solid than the one of the sea. The positions and structure of its teeth with more space in between correspond to an alimentation with smaller fishes. The larger eyes and higher haemoglobin level in its blood are designed for deeper waters to find their favourite food.
Method 2: comparing parasites
The parasites on the nierpa (in French, “vers parasites et pous”) and the ones on the Phoca hispida have many similarities, while they are totally different from the ones on the Phoca caspica for example (Pasthoukov, 1982, 1993).
Method 3: using genetic tests
Unfortunately, the more recent genetic method does not allow confirming the classification confirmed by methods 1 and 2. The genetic similarity within the Phoca family is at 55% between the 4 sub-families, taken two by two. Therefore, the similarity between nierpa and Phoca hispida are not stronger than with other Phoca sub-families, and does not lead to a clear classification.
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