![]() Vilizzi and Walker 1999 Khan and Khan 2009). Various calcified structures (or ‘hard parts’), including scales, opercula, vertebrae, spines, fin rays and otoliths (Casselman 1983), are available for ageing fish, and these structures are sometimes used in conjunction for comparative purposes (e.g. Hilborn and Walters 2013) and for understanding species’ life histories and their population dynamics (Beddington and Kirkwood 2005). It is suggested that dorsal spines or pectoral fin rays should be used in lieu of scales as non-lethal ageing structures, and otoliths (or vertebrae, pending more research) otherwise, and that validation should always be attempted as part of the set-up of more appropriate ageing protocols and use of correct terminology.Īge determination in fish is fundamental for the management of fisheries (e.g. Accuracy was addressed sporadically and mostly in high-risk countries. ![]() Precision was always above reference thresholds for scales, whereas for otoliths, dorsal spines and fin rays was in several cases below. Causal criteria analysis showed scales and opercula to provide inconsistent evidence for successful annulus identification/counting, whereas consistent evidence was found for otoliths, dorsal spines, vertebrae and (pectoral) fin rays. However, in countries where carp is categorised as ‘high risk’ of impact, use of alternative structures to the scale was predominant. Historically, scales were by far the most widely-employed structure, followed by the operculum, otolith, dorsal spine, vertebra and fin ray. The present study provides a global review of age determination in carp, including a historical account of ageing methods, an assessment of the relative utility of ageing structures, and an evaluation of precision and accuracy (i.e. Due to its value for conservation and fisheries in several native/translocated areas of distribution and its detrimental effects on the aquatic ecosystem in most invasive areas, robust age-based population dynamics models are required for successful management of this species. The common carp Cyprinus carpio is one of the most widely-distributed freshwater fishes in the world.
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