Jumbo squid (Dosidicus gigas) landings in the Gulf of California related to remotely sensed SST and concentrations of chlorophyll a (1998–2012)

Abstract

The jumbo squid Dosidicus gigas supports an important fishery in the central region of the Gulf of California, Mexico. However, in recent years, landings of this species in the port of Guaymas, Sonora has declined significantly. We examined monthly landing records from January 1998 through March 2012 and related this record to monthly sea surface temperature (SST) and chlorophyll a from satellite imagery and coastal upwelling index (CUI) in the fishing area as proxies of inter-annual changes in the epipelagic habitat. Results indicate that jumbo squid catches were high between June 1999 and December 2004 (328,903t) associated with an extended period of prevailing cold SSTs (La Niña 1999) and high chlorophyll a concentrations with intense CUI. From January 2005 through March 2012, a progressive catches decrease; landings were about 31.8% of previous captures (104,829t). Decline is associated with a progressively warmer habitat with less chlorophyll a and considerably lower CUI. Six fishing surveys carried out into the central Gulf of California with jig sampling indicate that jumbo squid tend to be in regions with low SST and high chlorophyll a, confirming its association with cold and productive areas.