Preliminary results of research on mackerel stock genetics in Icelandic waters show that it can not be ruled out that a small proportion of it is of non-European origin. In the coming months, the results of a strong genetic analysis will determine whether and in what proportion the mackerel in this country will come from the west.
Recently, Kjartan Stefánsson at Fiskifréttir gave an interesting interview to Anna Kristín Daníelsdóttir, director of Safety, Environment and Genetics at Matís. The interview is here in its entirety, but it had previously appeared in Fiskifréttir.
Scientists from the Marine Research Institute, Matís and the University of Iceland, as well as Norwegian, Faroese, Greenlandic and Canadian scientists, began researching mackerel in the North Atlantic two years ago in collaboration with several companies. Among them are Huginn ehf, Síldarvinnslan hf, Vinnslustöðin hf. and Framherji aps. Funding from the Fisheries Project Fund launched the project in 2011, followed by funding from the Faroese Research Council and the Nordic NORA Fund. Rannís has also provided funding for the project. The project is called: "North Atlantic mackerel stock genetics - is the stock exclusively European?"
Dr. Anna Kristín Daníelsdóttir, division manager at Matís ohf., Is the project manager in the part of the research funded by the Fisheries Project Fund, while Christophe Pampoulie, genetics specialist at the Marine Research Institute, is the project manager in the NORA project.
Final results from the project are not available, but results from preliminary research have been presented to participants. Despite the fact that the mackerel that enters Icelandic jurisdiction is for the most part European, there are indications that it is to some extent of Canadian origin, according to Anna Kristín Daníelsdóttir in a conversation with Fiskifréttir. However, she noted that the ability of the method on which these results are based to distinguish between stocks in the western and eastern Atlantic was too weak to make unequivocal claims that Canadian mackerel is found in Icelandic waters and in what proportion.
Number of samples
A total of 1414 samples were genetically analyzed within this project. The reference database consisted of samples of spawning grounds from France, Ireland and Canada and the structure of these samples was examined. A total of 471 samples were collected in Icelandic waters in 2010 and 2011 and they were genetically analyzed with 15 selected genetic markers designed in the project. The Icelandic visions reflect the distribution of mackerel around the country. Using Roche sequencing technology (454 flx), 30 new so-called "microsatellite" genetic markers were designed. A peer-reviewed scientific article has been published describing the methodology and characteristics of these 30 genetic markers.
Three results
This study yielded three main results: 1) No significant genetic differences were found between the two European samples when examined with neutral microsatellite genetic markers. 2) Significant genetic differences were found between samples from Europe and Canada. Although transatlantic gene flow is restricted, the genetic difference is smaller (1.6%) than expected if the results are compared with other pelagic species such as herring. 3) The majority of mackerel caught in the Icelandic fishing zone is of European origin, as mentioned before, but it is possible that a small part is of Canadian origin. Mackerel of Canadian origin appear to be found throughout the waters around Iceland, which raises a number of questions that will also be addressed.
It should be emphasized that the statistical basis of this study is weak and further research is underway. The next steps in the research are to find more sensitive genetic markers that differentiate better between strains and thus apply the latest genetic analysis technology in developing selective differentiating genetic markers (eg SNP genetic markers).
Clear differences between mackerel in Canada and in Europe
Anna noted that there was a significant genetic difference between European mackerel in the west of Ireland and the Bay of Biscay on the one hand and mackerel with Canada on the other. However, this genetic difference would be smaller than for herring stocks that remain in the corresponding sea areas. This is probably explained by the mackerel's behavior and behavior, but the mackerel's distribution area is very extensive.
The status of the project
Anna was finally asked what the status of the project was. "We are currently working on further sample collection, statistical analysis and samples are being examined better with new genetic markers (SNPs). This will make it possible to obtain clearer and more reliable information on the genetics of mackerel in Icelandic jurisdiction. The first indications of this are expected this autumn.
The NORA co-operation project is now in its second year out of three. After a year, we believe that it will be possible to answer with more certainty whether and to what extent the proportion of mackerel in this country will come from the west. It takes two to three years to develop a methodology, collect samples and establish a partnership. We are also looking at this project as a basis for further research and that the results can be used in stock assessment, fisheries management and fishing in the future, "said Anna Kristín Daníelsdóttir.
For further information Anna Kristín Daníelsdóttir.