New research reveals how herring genes vary with the environment. The discovery could make it easier to protect the herring stock against future challenges such as climate change, writes ScienceNordic based on resultats from DTU Aqua PhD dissertation.
Since the sea has no borders, it was once thought that all herrings belong to the same large stock. It was therefore believed that herrings were free to swim around and mingle with other herrings. But a new Danish study provides an insight into a hitherto unknown degree of diversity in the herring stock, writes ScienceNordic in an article based on a phD dissertation by post. doc. Morten Limborg, DTU Aqua.
Herrings adapt to their environment
“Up to 20-30 years ago it was believed that there was not much difference between fish species such as herring and cod,” says Morten Limborg to ScienceNordic:
“But we have found great genetic differences between the stocks, depending on the surrounding environment.”
Specifically, the study suggests that the herring in Nordic waters can be divided into four genetically distinct groups, based on where they come from:
1. The eastern part of the Baltic Sea
2. The western part of the Baltic Sea
3. The North Sea
4. The North Atlantic
The findings are not only valuable on a theoretical level – they have practical applications too.
From time to time, the herrings from areas 2-4 mentioned above meet in the Skagerrak Strait, which is located between northern Denmark and southern Norway.
”If the fishermen suddenly overfish a certain stock of herring, we can now easily modify the fishing quotas on a continuous basis, and that way we can promote the survival of the stock,” Morten Limborg says to ScienceNordic.
“We’ve improved our ability to distinguish one herring from another, so now it’s a lot easier to monitor the fishery.”
Read the complete ScienceNordic article online:
http://sciencenordic.com/diverse-herrings-are-super-survivors
Further information:
Post. doc. Morten Limborg, DTU Aqua
mol@aqua.dtu.dk
About ScienceNordic:
ScienceNordic, launched in November 2011, offers science news from the Nordic countries – in English. It is the a joint effort from two science news services in the region, Forskning.no in Norway and Videnskab.dk in Denmark, who work in close collaboration with partners in Sweden, Finland, Iceland, Greenland, the Faroe Islands and Åland.
www.sciencenordic.com