Up to 20 new salmon stocks found in the Teno River, Finland

Using evolutionary genetic methods, Juha-Pekka Vähä and Professor Craig Primmer discovered that salmon from tributaries such as Pulmanki, Utsjoki and Iesjoki are so genetically different from each other, they can be considered as completely separate stocks.

The finding confirms what many local fishermen and indeed researchers have long suspected, and has important implications for salmon conservation in Finland as until now, it had been assumed that the number of naturally reproducing Finnish salmon stock was just 4 – Teno, Näätämö (Neiden in Norwegian), Tornio (Torneå in Swedish) and Simo. 32 former Finnish salmon populations have gone extinct. “Our results show that the number of Finnish salmon populations is actually much higher than four, as the tributaries of Teno can actually be considered as separate populations which are genetically more different than the salmon of many Baltic Sea salmon rivers are from each other, even though the Baltic rivers are separated by hundreds of kilometres, and the Teno tributaries by just tens” said Vähä who conducted the research as a part of his PhD thesis.

The researchers also found that the presence of large, multi sea-winter fish in a population was important for the genetic diversity of a population. “Overall, the findings of our study emphasise the large contribution of Teno salmon to Finnish salmon biodiversity, and provide useful information for the management and conservation of this valuable natural resource.” continued Vähä.

A scientific article reporting the results of Vähä and Primmer’s findings, in collaboration with Jaakko Erkinaro and Eero Niemelä from the Finnish Game and Fisheries Research Institute, has been recently published in the international science journal – Molecular Ecology.

The Maj and Tor Nessling funded project is one of a number of applied evolutionary genetics projects carried out in Primmer’s research group, which is a part of the Centre of Excellence in Evolutionary Genetics and Physiology funded by the Academy of Finland.