The Humboldt squid is a large squid that lives throughout the eastern Pacific Ocean. It is named after an explorer who visited that region at the turn of the 18th and 19th centuries and is also often called the jumbo squid, as a result of its size. This species is the largest of the flying squids, with mantles (another word for bodies) at least four feet (1.2 m) long and tentacles at least another couple of feet. It can reach weights of over 110 pounds (50 kg), and is one of the most common large predators throughout its range.
Like many squids, the Humboldt squid grows rapidly and likely lives for only a single year. During that time, it reaches its maximum size, reproduces multiple times, and dies. Humboldt squid reproduce via internal fertilization and lay large egg masses of at least one million eggs. In their short lifetime, females may lay as many as 20 million eggs, the most of any known cephalopod (squid, octopus, or relative). After they hatch, Humboldt squid grow from about one millimeter to well over a meter in just one year. To support a growth rate that high, Humboldt squid are voracious predators and have been known to decimate populations of small fishes or smaller squids when their numbers explode. Several species prey on this Humboldt squid throughout the many life history stages, but adults are a favorite food of sperm whales, billfishes, and other very large predators.
Humboldt squid are excellent swimmers and are covered in specialized color cells that allow them to rapidly and repeatedly change color. This behavior is used to both communicate with others and to display warning coloration to other species. On very rare occasion, individuals have been known to act aggressively toward SCUBA divers who were diving in groups of Humboldt squid that were feeding. These interactions are likely a result of mistaken identity by the squid.
In recent decades, the Humboldt squid has undertaken a massive expansion in geographic range. Historically, it was common from Peru to central Mexico, but now they stretch from the tip of Chile to Alaska. There is a very large population in the Gulf of California, Mexico that scientists believe only recently became established there, and this species is now common throughout California. There are large commercial fisheries for Humboldt squid in Mexico and in Peru, and a sport fishery has developed in California. In Mexico, several hundred metric tonnes are captured every night by hand by artisanal fishers who sell their catch to a single local processing plant. Though this species is fairly well studied, its conservation status is currently unknown. Its expanding range and apparently increasing numbers in some places may be balanced by increasingly large fisheries in other areas. As it is an important prey species for charismatic, protected species like sperm whales and an important fishery species for small-scale fishers throughout its range, it is vital that scientists determine its population trends and continue to study its biology and ecology.