To the top

Page Manager: Webmaster
Last update: 9/11/2012 3:13 PM

Tell a friend about this page
Print version

Larval group differentiat… - University of Gothenburg, Sweden Till startsida
Sitemap
To content Read more about how we use cookies on gu.se

Larval group differentiation in Atlantic cod (

Journal article
Authors V. Oresland
Carl André
Published in Fisheries Research
Volume 90
Issue 1-3
Pages 9-16
ISSN 0165-7836
Publication year 2008
Published at Department of Marine Ecology, Tjärnö Marine Biological Laboratory
Department of Marine Ecology
Pages 9-16
Language en
Links <Go to ISI>://000255266900003
Keywords cod, gadus morhua, larvae, spawning, hatch dates, genetic, otoliths, vertical distribution, dispersal, early-life-history, population-structure, north-sea, otolith microstructure, georges bank, juvenile cod, shelf break, newfoundland, variability, skagerrak
Subject categories Biological Sciences, Pharmacognosy

Abstract

The spatial and temporal occurrence of pelagic fish stages and their biological variability may affect their dispersal and survival, and ultimately fish recruitment. We collected Atlantic cod larvae at one station inside and at one station outside the Gullmar Fjord, eastern Skagerrak, in order to investigate small-scale larval group differentiation. Rectangular midwater trawl hauls were taken every 6 h (during 24 h) from three separate depth intervals between the surface and 70 m depth. About 80% and 20% of all larvae occurred above the halocline at the Fjord station and the Coastal station, respectively. Hatching (at both stations) occurred from the 3rd week in February to the 1st week in May, indicating that cod larvae were present for at least 5 months (from late February to early August). The length and hatch date frequency distributions of larvae from the surface layer were unimodal inside the fjord but bimodal outside the fjord. Analyses of seven microsatellite DNA loci indicated that larvae collected inside the fjord (where local spawning occurs) were genetically distinct from larvae sampled on the outside (F-ST = 0.0026). The two age cohorts outside the fjord were not, however, genetically different, nor were larvae collected at different depths. We conclude that small-scale variability of vertical concentration and larval life history variability should have consequences for interpreting models of larval dispersal and survival, and subpopulation structure analyses. (C) 2007 Elsevier B.V. All rights reserved.

Page Manager: Webmaster|Last update: 9/11/2012
Share:

The University of Gothenburg uses cookies to provide you with the best possible user experience. By continuing on this website, you approve of our use of cookies.  What are cookies?