Dosidicus gigas is a fast growing predator in the eastern Pacific Rim with a high energy demand. Since 2000, it has been found in waters beyond its until-then-known northern and southern distribution limits. At the same time, specimens in the southern hemisphere were observed to reach maturity at significantly larger sizes. Spatio-temporal differences in temperature and food abundance may explain population changes in maturation, growth, and migration. Size-at-maturity depends on temperature and food availability, meaning jumbo squid will mature at smaller sizes under warm conditions and at larger sizes that can migrate longer distances in cool conditions. In this paper,we present the hypothesis that the present invasion of jumbo squid into formerly uninhabited areas was the result of a combination of favorable environmental conditions and fishery impacts: the regime shift from warm to cool water following a strong La Niña/El Niño combined with the fisheries' impact on competitors and predators of D. gigas opened up a previously unavailable niche, or "loophole," and allowed for the present spatial expansion of jumbo squid.