Growth of common carp Cyprinus carpio in Anatolia (Turkey), with a comparison to native and invasive areas worldwide
Özet
Common carp Cyprinus carpio occurs in several non-native areas worldwide, where it is generally regarded as either naturalised or invasive. Anatolia (Turkey) represents a unique region for evaluating common carp growth, due both to its location at the southernmost range of expansion of the species' wild form and to most of its water bodies having been stocked with domesticated strains. Based on a review of length-at-age data for common carp stocks from 45 water bodies sampled between 1953 and 2007, regional patterns in growth across climates, water body types, scalation variants and sexes, along with altitudinal gradients in growth performance and mortality, were investigated. Growth rates were lower in cold and arid relative to temperate climates, and also under hot or dry summers; this was true also of the mirror relative to the scale variant, males to females, but not of water body types (i.e., man-made reservoirs, natural lakes, water courses). Growth performance and mortality decreased with increasing altitude and decreasing temperature, likely due to optimisation of resource allocation between growth and reproduction. Growth rate of common carp from Anatolia was consistently lower compared to its native (Eurasian) and, especially, invasive (North American) counterparts, which reflected an opportunistic life-history strategy. Lower growth rates in Anatolia were ascribed to lower resilience of the widespread mirror variant together with limited habitat for spawning in man-made reservoirs. Better knowledge of common carp growth in Anatolia will improve stock management and conservation efforts. Further studies will help clarify the mechanisms responsible for evolutionary genotype-phenotype inter-relationships.
