Validation of ageing techniques on otoliths of horse mackerel (Trachurus trachurus L.)
Eltink, A.; Kuiter, C.J. (1989). Validation of ageing techniques on otoliths of horse mackerel (Trachurus trachurus L.). CM Documents - ICES, C.M. 1989(H:43). International Council for the Exploration of the Sea: Copenhagen. 10 + figures pp. Part of: ICES CM Documents - ICES. ICES: Copenhagen. ISSN 1015-4744, more | |
Keywords | Age determination Age determination > Otolith reading Conferences Trachurus trachurus (Linnaeus, 1758) [WoRMS] Marine/Coastal |
Abstract | Except in young fish, age determination in the horse mackerel (Trachurus trachurus) presented considerable difficulties. At the Horse Mackerel Age Determination Workshop in Lowestoft (UK) in 1987 ten otolith readers participated of which nine used the same ageing technique, but only one used another ageing technique, which ageings differed about a factor two. The ageing technique of this majority is likely to be the most accurate one based on the collected evidence. The occurrence of annual year-marks is tested by following identifiable year classes through successive year age compositions, because only one out of the two existing age interpretation methods can do so. |
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