1. Population structure of demersal fish species in the north eastern Atlantic
- Author
-
O'Sullivan, Martha
- Subjects
591.35 ,Deep-sea fishes ,Fishes ,Fishery resources - Abstract
Neutral microsatellite markers were used to analyse genetic variation in three demersal finfish species, whiting (Merlangius merlangus) haddock (Melanogrammus aeglefinus) and anglerfish (Lophius piscatorius) in the north east Atlantic. For each species samples were collected from the North Sea and west of the British Isles while geographically distant samples were also collected from Icelandic waters. In the case of the anglerfish study samples were also taken from the Bay of Biscay and the Mediterranean Sea. Whiting appears to show the highest level of structuring in the north east Atlantic with samples from Icelandic waters being significantly divergent from samples on the continental shelf. Just one of the continental shelf haddock samples, the Irish Sea, showed evidence of divergence from the Icelandic samples. This general lack of divergence between Icelandic and continental shelf haddock is most likely reflective of a combination of relatively recent isolation and large effective population sizes (N
e ). Apart from a few significant results (P<0.05) continental shelf haddock and whiting conspecific populations tended to show little divergence. This would also appear to be due primarily to large effective population sizes and a relatively recent isolation. L. piscatorius showed a total absence of genetic differentiation between all the Atlantic samples which is consistent with the long distance movements associated with this species. There was however strong evidence of divergence between the Atlantic and Mediterranean anglerfish samples. Comparing the results of the molecular studies presented here with non molecular approaches to determining population structure highlights the importance of combining information from several approaches if a sustainable management plan is to be put in place for commercial species.- Published
- 2009