Feeding Habits of Sarda chiliensis chiliensis (Cuvier, 1832) in Northern Chile and Southern Perú

SIMPLE SUMMARY: Knowing the biology of fish, preferably for this study of trophic relationships, is fundamental to advance in the culture technologies of this species, since knowing what they feed on will allow us to generate a species-specific food for the species and thus be able to obtain a fast and efficient growth. The objective of this research was to analyze the feeding habits of South Pacific bonito by sex and season between summer and autumn in three locations in the South Pacific, using trophic biology techniques. A total of 1404 stomachs were analyzed, corresponding to 420 specimens from the Pozo de Lisas area, 540 specimens from the La Capilla area and 444 specimens from the Chanavayita area. Dynamic indexes of feeding analysis and trophic composition of the diet were used. Under the analysis carried out in this research, we can conclude that fish feed more during autumn; in addition, the prey hierarchy of this species was Pleuroncodes monodon and Engraulis ringes. That said, and in view of the results, it would be a generalist species. ABSTRACT: The trophic relationships of pelagic fishes with migratory traits such as the South Pacific Bonito, Sarda chiliensis chiliensis (Cuvier, 1832), have not been studied in depth in the past. The objective of the present research was to analyze the feeding habits of South Pacific Bonito by sex and to analyze a comparison between summer and autumn months in three different areas of the eastern South Pacific by applying different techniques used in trophic biology. Between December 2013 and June 2014, specimens were captured in the areas of Pozo de Lisas (Ilo, Peru), La Capilla (Arica, Chile) and Chanavayita (Iquique, Chile). The feeding dynamics and trophic composition of the diet were analyzed, as well as the feeding strategy and trophic relationships. A total of 1404 specimens were analyzed, of which 654 had stomach contents. Seven prey items were identified: (a) fish remains; (b) squid jaw remains; (c) squid gladius remains; (d) caudal fin remains; (e) Engraulis rigens; (f) Pleuroncodes monodon and (g) N/A (not determined). The Pozo de Lisas and La Capilla areas showed homogeneity in their prey items, while the Chanavayita area showed more diversity. Regarding the importance of prey items in the diet of S. chiliensis in the three localities, it would be correct to state that it is a generalist species.