Stomach contents of 533 jumbo squid, Dosidicus gigas, ranging between 14·5 and 87·5 cm dorsal mantle length were collected on a monthly basis in the central Gulf of California from November 1995 to April 1997. Fish prey were identified by sagittal otoliths, cephalopods by beaks and crustaceans by exoskeletal features. The diet was dominated by Benthosema panamense, an abundant near-shore nyctoepipelagic myctophid that forms dense aggregations. Another myctophid, Triphoturus mexicanus, several micronektonic squid, pelagic red crab and small pelagic fish such as northern anchovy and Pacific sardine played a secondary role. The largest differences in diet were due to spatial and monthly changes, while differences regarding squid size or sex were smaller. Prey size (averaging 5–7 cm) and prey number did not vary with size of jumbo squid. Jumbo squid in the slopes of the Guaymas basin feed on abundant schooling mesopelagic micronekton of annual nature with a quick response to environmental changes, which could partly explain the large annual fluctuations of this commercial resource.

Climate change is an environmental emergency threatening species and ecosystems globally. Oceans have absorbed about 90% of anthropogenic heat and 20%–30% of the carbon emissions, resulting in ocean warming, acidification, deoxygenation, changes in ocean stratification and nutrient availability, and more severe extreme events. Given predictions of further changes, there is a critical need to understand how marine species will be affected. Here, we used an integrated risk assessment framework to evaluate the vulnerability of 132 chondrichthyans in the Eastern Tropical Pacific (ETP) to the impacts of climate change. Taking a precautionary view, we found that almost a quarter (23%) of the ETP chondrichthyan species evaluated were highly vulnerable to climate change, and much of the rest (76%) were moderately vulnerable. Most of the highly vulnerable species are batoids (77%), and a large proportion (90%) are coastal or pelagic species that use coastal habitats as nurseries. Six species of batoids were highly vulnerable in all three components of the assessment (exposure, sensitivity and adaptive capacity). This assessment indicates that coastal species, particularly those relying on inshore nursery areas are the most vulnerable to climate change. Ocean warming, in combination with acidification and potential deoxygenation, will likely have widespread effects on ETP chondrichthyan species, but coastal species may also contend with changes in freshwater inputs, salinity, and sea level rise. This climate‐related vulnerability is compounded by other anthropogenic factors, such as overfishing and habitat degradation already occurring in the region. Mitigating the impacts of climate change on ETP chondrichthyans involves a range of approaches that include addressing habitat degradation, sustainability of exploitation, and species‐specific actions may be required for species at higher risk. The assessment also highlighted the need to further understand climate change's impacts on key ETP habitats and processes and identified knowledge gaps on ETP chondrichthyan species.