Potential growth and yield of one- and two-year-old carp, Cyprinus carpio L., in climatic conditions of la Dombes (France)

Abstract

The potential growth and yield of 1‐ and 2‐year‐old carp, Cyprinus carpio L., in climatic conditions similar to those of la Dombes were determined by a stochastic‐deterministic model, derived from data on growth of Polish carp cultured under intensive methods. The model's forcing functions are the water temperature, effective for carp body mass growth, recorded in ponds of la Dombes, the final fish density, the protein content in feeds and the initial body mass (for 2‐year‐old fish). It was assumed that the pond ecosystem does not limit fish growth and that the pond trophic chain works correctly. Quantification of relations between basic elements of the carp culture techniques enables prediction of the required final output from ponds, permitting the most efficient culture methods to be chosen.

Validating Otolith Annuli for Annual Age Determination of Common Carp

“…Our regular sampling of this juvenile cohort was equivalent to ''sampling length modes for age structure'' that is described as a viable method for validating the interpretation of annuli in young fish (Campana 2001). Studies of juvenile common carp growth and ontogeny, as well as the absence of any visible annuli on the otoliths of the 1999 juvenile cohort from Hut Lake, support our assumption that this cohort was composed of age-0 fish (Chakrabarti and Jana 1992;Szumiec 1997;Vilizzi 1998). Accepting this assumption, sampling length modes for age structure is essentially the validation of absolute age for age-1 common carp (one of the key requisites of age validation; Campana 2001).…”