Skip Navigation


ICES Journal of Marine Science: Journal du Conseil Advance Access originally published online on June 8, 2009
ICES Journal of Marine Science: Journal du Conseil 2009 66(9):1899-1914; doi:10.1093/icesjms/fsp153
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
66/9/1899    most recent
fsp153v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Lambert, G.
Right arrow Articles by Sparholt, H.
PubMed
Right arrow Articles by Lambert, G.
Right arrow Articles by Sparholt, H.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© 2009 International Council for the Exploration of the Sea. Published by Oxford Journals. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org

Maturity and growth population dynamics of Norway pout (Trisopterus esmarkii) in the North Sea, Skagerrak, and Kattegat

Gwladys Lambert1, J. Rasmus Nielsen1, Lena I. Larsen2 and Henrik Sparholt2

1 National Institute of Aquatic Resources (DTU AQUA), Technical University of Denmark, Charlottenlund Castle, DK-2920 Charlottenlund, Denmark
2 International Council for the Exploration of the Sea, H. C. Andersens-Boulevard 44-46, DK-1553 Copenhagen V, Denmark

Correspondence to J. R. Nielsen: tel: +45 33 96 33 81; fax: +45 33 96 33 33; e-mail: rn{at}aqua.dtu.dk

Lambert, G., Nielsen, J. R., Larsen, L. I., and Sparholt, H. 2009. Maturity and growth population dynamics of Norway pout (Trisopterus esmarkii) in the North Sea, Skagerrak, and Kattegat. – ICES Journal of Marine Science, 66: 1899–1914.

The population dynamics of the Norway pout stock in the North Sea are investigated by statistical analyses, and GIS of ICES International Bottom Trawl Surveys (IBTS) and Danish commercial catch data from 1983 to 2006. The stock spawns mainly around mid-February along the northeastern English and Scottish coasts and between Shetland and Norway. Sex ratios indicate that males, which mature younger than females (age-at-50%-maturity, respectively, 1.2 and 1.5 years), migrate out of the Skagerrak–Kattegat to the spawning grounds before females. There is a decrease in the 2+-group maturity ratios as well as in weight and female length from before to after spawning. The results indicate spawning mortality. Only some 20% of the 1-group reaches maturity in the first quarter, which is higher than assumed in the stock assessment. Although the maturity ogives are variable over time, this difference should be taken into account when estimating spawning-stock biomass in routine assessments. Growth is also variable, with a tendency for male maximum length to be smaller than that of females, and immature fish to be smaller than mature ones in each age group. The juvenile growth rate is higher when the stock density is low and results in a reduced age-at-50%-maturity. Besides these intraspecific patterns, the growth rates show interspecific links to stock sizes of the important predators: cod, haddock, and whiting.

Keywords: density-dependence, intra- and interspecific growth, maturity, North Sea, Norway pout, population dynamics, spawning, spawning mortality, Trisopterus esmarkii

Received 12 April 2008; accepted 20 March 2009; advance access publication 8 June 2009.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.