Management of Dosidicus gigas, a large, pelagic predator in the eastern North Pacific Ocean

Abstract

The Humboldt squid (Dosidicus gigas) has been expanding its geographical range in the eastern North Pacific Ocean over the past 20 years. This species of squid has advanced from the most southern part of their native range, off the Chilean coast, northward to southern Alaska. This expansion of a fast-growing pelagic predator is concerning and should be evaluated. Dosidicus gigas has been known to negatively affect native species of fish populations, such as Pacific hake (Merluccius productus), when expanding its range. The effects of an establishment of a D. gigas population in Pacific Canadian waters on both ecological systems as well as commercial fisheries should be assessed to develop management plans to protect native species and commercial fisheries. The reduction of potential effects of D. gigas establishment on native species of the eastern North Pacific is essential to conserving current native populations. A complete list of trophic interactions between D. gigas and species native to the eastern North Pacific is still underdeveloped. To qualitatively assess what is driving the migratory behaviour of D. gigas, the physiological, reproductive, and ecological traits of the species are reviewed here. The results indicate that warming water temperatures, reproductive plasticity, and prey/predator interactions are the leading causes thought to be driving D. gigas northward.