Spatio-temporal Analysis on Nutritional Condition of Engraulis Anchoita Larvae: Its Relation with Hydrographical Features of Nursery Grounds and Food Availability

Tesis En Ciencias Marinas, Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, 2010

M.V. Díaz

“Nutritional condition studies allow the assessment of physiological state of each larva and thus, the establishment of favourable nursery areas which provide better survival and growth. In the present work, morphometrical, histological and biochemical techniques were employed to assess nutritional condition of anchovy, Engraulis anchoita, larvae captured in the Argentine Sea. Its results were complemented with oceanographic data and information about zooplankton abundances, both prey and predators of anchovy larvae. Anchovy larvae abundance and distribution would be mainly determined by physico-chemical variables. Even though no significant differences were found in larval nutritional condition among the studied areas, larval condition was slightly better in frontal areas characterized by mixed water masses. On the other hand, anchovy larvae condition seems to be favoured during seasons when larval abundances remain low. Probably, ocean conditions are almost always favourable for larval growth and survival during the whole year, but low or intermediate larval densities allow avoiding both intra and inter-specific competition. As only a small number of anchovy larvae were described as in starving condition, it can be assumed that E. anchoita, finds environmental conditions that favour its growth and survival. during all seasons in the studied area.”