Naupliar growth versus egg production in the calanoid copepod Centropages typicus

Abstract

Growth rates of the copepod Centropages typicus were assessed during May 1998 in the Alboran Sea. The goal of the work was to compare field growth rates of juvenile (artificial cohort method) and adult copepods (female egg production rates) under an extensive range of natural conditions. The results showed that adult and juvenile growth rates were similar in some stations, while in others no such relationship was apparent. In contrast to the common belief that juvenile growth may be saturated under natural conditions whereas adults may be food-limited, in most of our study, adult growth rates were greater than juveniles. We discuss these results in the light of food availability at the surveyed stations. In summary, the assumption that copepod growth rates estimated through egg production rates of adults are equivalent to juvenile growth is not always valid.