Daily growth patterns of juveniles and adults of the Peruvian anchovy (Engraulis ringens) in northern Chile

Abstract

Abstract. The Peruvian anchovy (Engraulis ringens) is a resource of considerable economic importance, whose stock unit is distributed between 16800 0 S and 24800 0 S and is shared between Chile and Peru. In the present study, daily growth patterns of juvenile and adult Peruvian anchovies in northern Chile were determined using micro-increments of sagittal otoliths for the recruitment and fishery seasons of 2009 and 2010. A characteristic feature was the existence of very distinctive daily micro-increments, through which a complete sequence of micro-increments was obtained from the primordium to otolith edge for juveniles (7.5-12-cm total length (TL)) and adults (12.5-18.0 cm TL), whose ages were in the range 56-166 and 137-409 days respectively. Hatch dates extended from July 2009 to July 2010, where juveniles recruited to a fishery in a given month were the survivors of a spawning that had occurred approximately 3-4 months before. A Laird-Gompertz model fitted to length-at-age data for juveniles estimated maximum instantaneous growth rates that ranged from 0.98 to 1.57 mm day À1, whereas overall mean individual growth rates back-calculated for the age range of juveniles ranged from 0.65 to 1.02 mm day À1. The von Bertalanffy seasonal parameters estimated through the entire life history showed high growth, with a growth coefficient K ¼ 1.1 and mean length at the first year of 16.3 cm TL. Consequently, E. ringens in northern Chile seems to maximize growth in the first year of life.

Daily growth patterns and age‐at‐recruitment of the anchoveta Engraulis ringens as indicated by a multi‐annual analysis of otolith microstructure across developmental stages

“…In the case of the pre‐recruits, the age–length relationship showed a substantive increase in growth rate relative to the larval period, with maximum growth rates of c. 0.9 mm d −1 reached between the 30th and 70th days, supporting the results reported by Cerna and Plaza (). They demonstrated that most growth variability in E. ringens occurred during the first month of life.…”

“…The results derived from the interannual analysis of age at recruitment showed that, irrespective of year and season, juveniles typically recruit to the fisheries around 5 months after hatching, which provides further evidence of the fast growth of this species during its first year of life. Under a fast‐growth scenario, a large fraction of the asymptotic length can probably be reached within only a few months of life and consequently, the year‐class strength will be a product of the survival rates from just one season before and could have great relevance for the management of the anchovy fishery (Cerna & Plaza, ). The new scenario of accelerated growth in anchoveta reduces the time required to reach sexual maturity by half ( i.e.…”

“…In parallel with fitting the Laird‐Gompertz growth models to the length‐at‐age data from each catch date, growth models were also fitted to age‐at‐back‐calculated‐length data for recruits collected in 1973 and 1982. In addition, growth models were also fitted to back‐calculated data for the years 2009–2010 to obtain additional information on growth rates without overlapping the length‐at‐age data reported by Cerna and Plaza () for E. ringens in the same study area. The back calculation of L T at previous ages was carried out through the biological intercept method (BIM): L T = L C + ( R i –R C )( L C –L Th )( R C –R H ) −1 (Campana, ), where L TH is larval total length at hatching ( i.e.…”

“…These findings are supported by a recent study, which used a similar methodology to study anchoveta Engraulis ringens Jenyns 1842 in northern Chile, where absolute daily growth rates ( G AR ) between 1.2 and 1.3 mm d −1 were reported for juveniles < 12 cm total length ( L T ; Cerna & Plaza, ). Cerna and Plaza () found individuals of 8–12 cm L T had ages ranging from 56 to 166 days and they represented the survivors of spawning that occurring c. 3–4 months earlier. From all these evidences, it is reasonable to infer that some anchovy species tend to maximize growth during the first year of life.…”

European anchovy (Engraulis encrasicolus) age structure and growth rate in two contrasted areas of the Mediterranean Sea: the paradox of faster growth in oligotrophic seas

“…In short-lived species, such as small pelagic fishes, particular effort has been devoted to understanding the growth-mortality mechanism as it is considered the most important driver of recruitment variability of sardine and anchovy stocks (e.g., Jacobson & MacCall, 1995;Sinovčić, 1998;Allain et al, 2001;La Mesa et al, 2009;Schismenou et al 2014). On the contrary, only few studies have focused on the growth of adults, underlining the importance of growth on biomass production of populations (Van Beveren et al, 2014;Cerna & Plaza, 2016;Uriarte et al, 2016).…”