Reproductive success of the Argentine anchovy, Engraulis anchoita, in relation to environmental variability at a mid-shelf front (Southwestern Atlantic Ocean)

• Published in: Fisheries oceanography Vol. 22; no. 3; pp. 247 - 261
• Main Authors: Marrari, Marina, Signorini, Sergio R., McClain, Charles R., Pájaro, Marcelo, Martos, Patricia, Viñas, María Delia, Hansen, Jorge, Dimauro, Roxana, Cepeda, Georgina, Buratti, Claudio
• Format: Journal Article
• Language: English
• Published: Oxford Blackwell Publishing Ltd 01.05.2013
• Subjects: Animal reproduction; Annual variations; Blooms; Breeding success; Chlorophyll; Chlorophylls; Continental shelves; Duration; Dynamics; Ecosystem assessment; Ecosystem dynamics; Ecosystems; Engraulis anchoita; Environmental changes; Fish; Food; Food availability; Foods; frontal systems; Ichthyoplankton; Larvae; Marine; Marine ecosystems; Nutrient cycles; Nutrient dynamics; Ocean color; Ocean colour; Plankton; Recruitment; Recruitment (fisheries); Reproduction; SeaWiFS; South Atlantic Ocean; Spring; Stratification; Variability; Variation; Vertical distribution; Water stratification; Water temperature; Zooplankton; United States > US; Atlantic Ocean; ASW, Atlantic; Argentina, Buenos Aires Prov
• ISSN: 1054-6006; 1365-2419
• DOI: 10.1111/fog.12019

The mid‐shelf front (MSF) of the Buenos Aires province continental shelf in the Southwestern Atlantic Ocean plays a central role in the pelagic ecosystem of the region acting as the main spring reproductive area for the northern population of the Argentine anchovy Engraulis anchoita and supporting high concentrations of chlorophyll as well as zooplankton, the main food of anchovy. To investigate the influence of environmental variability on the reproductive success of E. anchoita, we analyzed a 13‐yr time series (1997–2009) of environmental data at MSF including chlorophyll dynamics, as well as zooplankton composition and abundance, ichthyoplankton distributions, and recruitment of E. anchoita. Spring chlorophyll concentrations showed high interannual variability and were mainly influenced by changes in water temperature and vertical stratification, which in turn control nutrient supply to the surface. Chlorophyll dynamics (magnitude, timing, and duration of the spring bloom) explained most of the variability observed in E. anchoita recruitment, most likely via fluctuations in the availability of adequate food for the larvae. Our results suggest that satellite ocean color products can be valuable tools for understanding variability in ecosystem dynamics and its effects on the recruitment of fish.