posted on 2024-04-25, 09:39authored bySondre Aanes, Michael Pennington
No abstracts are to be cited without prior reference to the author.
The assessment of Northeast Arctic cod is based on estimates of the commercial catch numbers at age. The age structure of the catch is estimated by sampling individuals from commercial fishing trips. Though it is commonly assumed that the sample of individuals is a random sample from the population, fish sampled from the same trip (i.e., from a ‘cluster’ of fish) tend to have more similar ages than those in the total catch. For Northeast Arctic cod, the intra-cluster correlation for age is positive and thus the effective sample size is much smaller than the number of fish aged. It is shown, given the number of fish aged, that the precision of the estimated age distribution is rather low, and that the number of fish aged from each trip could be reduced from approximately 80 to 20 without a significant loss in precision.
History
Symposia
2001 ICES Annual Science Conference, Oslo, Norway
Session
Theme Session P on Quality and Precision of Basic Data Underlying Fish Stock Assessment and Implications for Fisheries Management Advice
Abstract reference
P:01
Recommended citation
[Authors]. 2001. Assessing The Precision Of Commercial Catch At Age Estimates. 2001 ICES Annual Science Conference, Oslo, Norway. CM 2001/P:01. https://doi.org/10.17895/ices.pub.25636011