La valeur de la méthode otolithométrique pour la détermination de l'age du Merlu (<i>Merlucius merlucius</i> - Pisces, Gadidae) en Méditerranée


The otolithometric method rests on 2 (1) the agreement between the number of annual rings and the age of the fish and (2) the length of the fish being proportional to that of the otolith. The length of the fish may be grouped into 5 classes, ranging from 16, 18, 20, 25 to 27 cm though some degree of overlapping is observed. Using 300 otoliths and grouping the individuals according to the number of annual rings their otoliths bear it was possible to determine the frequency of individuals of varying lengths within a particular class. Although the results obtained by the author helped him to verify the 2nd parameter, numerous shortcomings were seen in this method. No consistent unity of measurement, which could be used for comparison, has been adopted by other workers; aberrant results were obtained by considering all the rings as being equivalent; the difficulty in interpreting an annual ring and the uncertainty of these deposits being regular and annual. It is strongly recommended that the otolithometric method be used only after its validity has been determined and a standard for reference in interpreting annual rings has been established

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