SWORDFISH GENETIC POPULATION STRUCTURE IN THE NORTH ATLANTIC AND MEDITERRANEAN
ICCAT considers the North Atlantic and the Mediterranean swordfish populations as two separate fish stocks and consequently recommends independent management actions for these two regions. Genetic analyses realized to date have confirmed genetic differentiation between these two areas, with a plausi...
| Main Authors: | , , , , , |
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| Other Authors: | |
| Format: | Text |
| Language: | English |
| Subjects: | |
| Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.596.1951 http://www.iccat.int/Documents/CVSP/CV061_2007/no_1/cv061010099.pdf |
| Summary: | ICCAT considers the North Atlantic and the Mediterranean swordfish populations as two separate fish stocks and consequently recommends independent management actions for these two regions. Genetic analyses realized to date have confirmed genetic differentiation between these two areas, with a plausible population substructure within the Mediterranean Sea. All these studies agree to establish the Strait of Gibraltar as the principal region to prevent gene flow between the North Atlantic and the Mediterranean. However, the present analysis realized with mitochondrial DNA sequence variation of new Atlantic samples together with Mediterranean swordfish showed that the phylogeographic signal, distinctive of the Mediterranean population, is also identified in a reduced part of the northeast Atlantic limited about 10º West. Surprisingly, in this area the phylogeographic signal of North Atlantic swordfish can also be recognized. Although extended sampling, with special focus on adjacent regions, is necessary to fully confirm this hypothesis, the results of the present genetic study indicate that the Mediterranean populations limit exceed the Strait of Gibraltar enclosing this northeast Atlantic region where a mixed stock can be found. |
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