Preliminary diet analysis of the blue shark Prionace glauca in the eastern South Pacific

Abstract

Abstract.-The diet of the blue shark Prionace glauca off central and northern Chile in the eastern South Pacific, during 2005 and 2006 were dominated by teleost fishes (72.21 %IRI) and cephalopods (27.07 %IRI). The seasonal feeding of blue shark showed as the most important prey diverse teleost fish species. Our findings would confirm that blue shark is a predator with wide trophic spectrum in the eastern south Pacific, although a higher number of stomachs need to be studied.

Diet of the blue shark Prionace glauca in the Ecuadorian Pacific Ocean during the years 2013 to 2015

“…Some squids, such as H. dofleini that inhabit deep waters between 400–1,500 m (Kubodera, ) may also be preyed upon during the day, as blue sharks can perform rapid daytime vertical migrations to depths of 300–600 m (Carey & Scharold, ). In contrast to our results, fishes dominated the diet of blue sharks in Chilean waters (>65% IRI; Lopez et al., ). The variety of prey consumed by blue sharks in the Pacific Ocean reflects the opportunistic feeding behavior of P. glauca .…”

“…The diversity of prey found in the stomach contents of P. glauca in Ecuadorian waters was higher than that found in the stomachs of sharks caught off the Pacific coast of Mexico and Chile (Galván-Magaña et al, 2013;Lopez et al, 2010;Pardo-Gandarillas, Duarte, Chong, & Ibáñez, 2007). Warm and cold waters converge near the equator, promoting a productive area for shark prey (Jiménez, 2008).…”

“…In the Pacific Ocean this predator feeds mainly on cephalopods (Markaida & Sosa-Nishizaki, 2010;Preti et al, 2012;Galván-Magaña et al, 2013;Rosas-Luis et al, 2016); in contrast, in the Eastern South Pacific fishes are the most prominent prey group in the blue shark diet (Lopez, Meléndez, & Barría, 2010).…”

Age and growth of the blue shark (Prionace glauca) in the Indian Ocean

“…When it comes to the diet of blue sharks, cephalopods are their most important prey type, squid in particular (Compagno, 1984;Henderson et al, 2001;Mendonça, 2009;Nakano and Stevens, 2008). Pelagic teleost fish are also a very common prey (Lopez et al, 2010;McCord & Campana, 2003). They can also feed on bottom fish (Nakano & Stevens, 2008), small sharks, invertebrates, mammals and even seabirds (Compagno, 1984).…”

Trophic ecology of the dusky catshark Bythaelurus canescens (Günther, 1878) (Chondrychthyes: Scyliorhinidae) in the southeast Pacific Ocean

“…Many chondrichthyes occupy an important ecological role as top predators in the marine environment, potentially regulating through predation the size and dynamics of prey species populations (Cort es, 1999). Therefore, trophic studies are useful to contribute to ecosystem analyses and consequently infer biological processes and fisheries interactions (Lopez et al, 2010). This in turn can be used to estimate food consumption and biomass of different species, quantify predator-prey relationships, and analyze energy flow between the elements of ecosystems in order to assess the impact of resources in the community structure, which subsequently are used in the integrated management of marine ecosystems (Lopez et al, 2012).…”