Energy Density Predictors for Argentine Anchovy Engraulis anchoita, a Key Species of the Southwestern Atlantic Ocean

Abstract

Forage fishes have a cosmopolitan distribution and constitute key species in marine trophic webs throughout the world. We estimated the energy density of the Argentine Anchovy Engraulis anchoita, a key component of the base of the food web in a large fraction of the southwestern Atlantic Ocean. We also examined the relationships between energy density and different proxies (condition factor, fork length, and percent dry weight) and compared the relationship of energy density to percent dry weight for Argentine Anchovy to this relationship in other forage fishes. A regression model that includes percent dry weight and fork length was the best predictor for the energy density in this species. The Argentine Anchovy had similar energy density to percent dry weight to all species in the Engraulidae family (anchovies) and to most of the species in the Clupeidae family (sardines). Engraulidae species showed smaller mean energy density and smaller energy density to percent dry weight compared with the Clupeidae species. The difference in energy density between these two families could have direct implications on population dynamics of predators in oscillating sardine–anchovy systems or in regions where these two families are spatially segregated.

Engraulis anchoita: Buratti, C., Díaz de Astarloa, J., Hüne, M., Irigoyen, A., Landaeta, M., Riestra, C., Vieira, J.P. & Di Dario, F.

“…The Buenos Aires stock is the larger of the two and is where the fishery is concentrated. Catch has remained well-below the total allowable catch limit and it is currently considered underexploited (Orlando et al 2019, Ciancio et al 2020. Biomass estimates have been conducted for the Buenos Aires stock since 1990; however, research cruises important to estimating stock biomass were not able to be carried out between 2008 to 2017.…”