Embryonic development and effect of temperature on larval growth of the Peruvian anchovy Engraulis ringens

Abstract

Understanding aspects of the biology of early life stages of marine fish is critical if one hopes to reveal the factors and processes that impact the survival and recruitment (year class) strength. The Peruvian anchovy (Engraulis ringens) is a key species in the Humboldt current system, and the present study provides the first description of the embryonic and larval development of this species reared in captivity. Embryonic and early exogenous feeding stages of larvae were illustrated in detail at 18.5°C. Hatching was completed within 42 and 48 h post-fertilization at 18.5 and 14.5°C, respectively. Mean ± 95% C.I. standard length (LS) at hatch (3.40 ± 0.10 mm at 18.5°C and 2.76 ± 0.34 mm at 14.5°C) was significantly different between the two temperatures. Larval behaviour was assessed at 18.5°C; at the onset of exogenous feeding [3 days post-hatch (dph)], larvae were fed small, motile dinoflagellates, Akashiwo sanguinea. At 7 dph, larvae started to feed almost exclusively on zooplankton (rotifers and Artemia nauplii). Larval activity increased with age, and the first sign of schooling was noted at 31 dph (18.56 mm LS) at 18.5°C. Temperature had a significant effect on size-at-age, but not on body shape (depth to LS ratio). The size-at-age data for larvae (this study) was used to parameterize a temperature-corrected von Bertalanffy growth function for Peruvian anchovy, the accuracy of which was assessed for juveniles and adults (literature values).