Summary: | Maturation in north-east-arctic haddock was studied in relation to fish age; length, weight and condition factor using data from scientific surveys in 1989-1998. In order to investigate the reliability of the maturity determination undertaken routinely onboard, gonads from 165 female haddock sampled during the Barents Sea trawl survey in January-March 1998, were studied in binocular. The size of the oocytes were measured, fitted to a 6-point maturity scale, and compared with the 5-point maturity scale.used. The results showed that the maturity determination of the routine sampling was reliable. Additionally, maturity at length and age was investigated for males and females 'using data from the winter surveys in 1989-1998 by fitting logistic curves. variations in maturity were compared with growth and condition. Males mature at a smaller size and younger age than females. Considerable year to year variations were found in length at 50% maturity in both sexes. Fluctuations in length and age at maturity followed similar trends, suggesting that length, as well as age, determine maturation.
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