Advanced

Condition indices of Atlantic cod (Gadus morhua) biased by capturing method

Ovegard, Mikael; Berndt, Kim LU and Lunneryd, Sven-Gunnar (2012) In ICES Journal of Marine Science 69(10). p.1781-1788
Abstract
In studies evaluating the condition and general health status of fish stocks, the method used for catching the fish is seldom considered as a factor of importance. In this study, condition indices were compared between cod caught in pots, gillnets, and on hooks in the same geographical area. The results showed that cod (Gadus morhua) caught on baited gear types (pots and hooks) generally displayed a lower condition and an older age (i.e. suggesting a lower growth rate) compared to cod caught in gillnets. It is unclear whether these results merely illustrate divergent behavioural responses in fish originating from one single population, or if these divergent behavioural components represent distinct subpopulations displaying different mean... (More)
In studies evaluating the condition and general health status of fish stocks, the method used for catching the fish is seldom considered as a factor of importance. In this study, condition indices were compared between cod caught in pots, gillnets, and on hooks in the same geographical area. The results showed that cod (Gadus morhua) caught on baited gear types (pots and hooks) generally displayed a lower condition and an older age (i.e. suggesting a lower growth rate) compared to cod caught in gillnets. It is unclear whether these results merely illustrate divergent behavioural responses in fish originating from one single population, or if these divergent behavioural components represent distinct subpopulations displaying different mean conditions and growth rates. Regardless of the underlying causes, the results not only show that parts of the Baltic cod stock are in extremely poor condition, they also indicate that different gear types used in the same area could target similar-sized conspecifics exhibiting large differences in condition and size-at-age. The potential impact of the difference in condition between the pots and other gear types could hamper the implementation of the cod pot as a potentially seal-safe and sustainable fishing method. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
capturing method, cod pot, Fultons condition factor, Gadus morhua, size-at-age
in
ICES Journal of Marine Science
volume
69
issue
10
pages
1781 - 1788
publisher
Oxford University Press
external identifiers
  • wos:000309877700009
  • scopus:84867515884
ISSN
1095-9289
DOI
10.1093/icesjms/fss145
language
English
LU publication?
yes
id
00d64f36-d6b5-47e3-8660-16d12daa78f9 (old id 3284115)
date added to LUP
2012-12-20 09:38:21
date last changed
2017-10-08 03:12:38
@article{00d64f36-d6b5-47e3-8660-16d12daa78f9,
  abstract     = {In studies evaluating the condition and general health status of fish stocks, the method used for catching the fish is seldom considered as a factor of importance. In this study, condition indices were compared between cod caught in pots, gillnets, and on hooks in the same geographical area. The results showed that cod (Gadus morhua) caught on baited gear types (pots and hooks) generally displayed a lower condition and an older age (i.e. suggesting a lower growth rate) compared to cod caught in gillnets. It is unclear whether these results merely illustrate divergent behavioural responses in fish originating from one single population, or if these divergent behavioural components represent distinct subpopulations displaying different mean conditions and growth rates. Regardless of the underlying causes, the results not only show that parts of the Baltic cod stock are in extremely poor condition, they also indicate that different gear types used in the same area could target similar-sized conspecifics exhibiting large differences in condition and size-at-age. The potential impact of the difference in condition between the pots and other gear types could hamper the implementation of the cod pot as a potentially seal-safe and sustainable fishing method.},
  author       = {Ovegard, Mikael and Berndt, Kim and Lunneryd, Sven-Gunnar},
  issn         = {1095-9289},
  keyword      = {capturing method,cod pot,Fultons condition factor,Gadus morhua,size-at-age},
  language     = {eng},
  number       = {10},
  pages        = {1781--1788},
  publisher    = {Oxford University Press},
  series       = {ICES Journal of Marine Science},
  title        = {Condition indices of Atlantic cod (Gadus morhua) biased by capturing method},
  url          = {http://dx.doi.org/10.1093/icesjms/fss145},
  volume       = {69},
  year         = {2012},
}