Effects of habitat conditions at hatching time on growth history of offspring European anchovy, Engraulis encrasicolus, in the Central Mediterranean Sea

Abstract

The knowledge of the growth history in young fishes represents an important aspect of fishery ecology. This is especially relevant in short-living species like European anchovy, since they suffer a high mortality rate in their early life stages until recruitment. Although it is well known that habitat condition significantly affects spawning dynamics of fishes, it is not yet clear if these conditions affect growth trajectories during the early life stage’s critical period. Otolith microstructure analysis has been proven a useful tool to back-calculate growth history of young fishes. Thus, we analysed the effect of habitat variability on their growth history using otolith microstructures and environmental variables obtained from satellite imagery. Growth trajectories in juvenile anchovies, collected in two recruitment surveys carried out in 2004 and 2005 in the Strait of Sicily, were characterized by means of three indices within the fast growing period: the maximum increment width, the mean value of increment width, and the time extension of the fast growing period. Obtained results evidenced a clear effect of environmental conditions, particularly of sea surface temperature and chlorophyll-a concentration, on the growth histories of juveniles of anchovy. Furthermore, delayed effects of environmental conditions at hatching time on the forthcoming growth dynamics were discussed.