Trophic ecology of Octopus mimus Gould, 1852; Doryteuthis gahi (d’Orbigny, 1835) and Dosidicus gigas (d’Orbigny 1835) (Cephalopoda) in 2016

Abstract

(O. mimus), common squid (D. gahi), and jumbo flying squid (D. gigas) are important commercial resources, hence the interest in monitoring their feeding habits by analyzing their stomach contents between February and December 2016. Octopus and Patagonian squid were fished in Callao Bay and Ilo, while the jumbo flying squid was caught in Paita, Camaná, and the area between Talara and Malabrigo. The dominant prey items were determined by the frequency of occurrence (%FO), numeric (%N) and gravimetric (%W) methods; besides fullness weight index (FWI) by sex, gonad and seasonal development. In octopus from Callao, the most important prey was Petrolisthes desmarestii, Cycloxanthops sexdecimdentatus, Pilumnoides perlatus, Synalpheus spinifrons; in Ilo P. perlatus, Cheilodactylus variegatus, and S. spinifrons. In Patagonian squid, the most important prey was indeterminate fish, crustacean Panopeidae, and polychaetes Nereidae. In jumbo flying squid from North (Paita), the most important prey were Vinciguerria lucetia, indeterminate squids, Pleuroncodes monodon; in the south (Camaná) were P. monodon, Chiroteuthidae cephalopods, and between Talara and Malabrigo, the dominant prey were Nyctiphanes simplex, indeterminate squids, and Cetengraulis mysticetus. The FWI tendencies were variable in some cases; in addition, the influence of the El Niño 2015-2016 on the feeding behavior was observed. Keywords: cephalopods, gastric contents, prey, trophic spectrum