The Humboldt squid (Dosidicus gigas) also called diablo rojo (red devil) or pota, jumbo flying squid, and jumbo squid, is a large predatory squid that inhabits the waters of the Humboldt current in the eastern Pacific Ocean.
It is regarded as the only known species of the genus Dosidicus of the subfamily Ommastrephinae under the family Ommastrephidae.
Humboldt squid typically reaches a mantle length of 4 ft 11 in (1.5 m), making it the largest member of its family. They are very aggressive towards humans, though this behaviour might have developed during feeding times.
Similar to other members of the subfamily Ommastrephinae, they are known to possess bioluminescent photophores and are also capable of changing body colouration (metachrosis). They rapidly flash white and red while hunting, which earned them the name diablo rojo (Spanish for the red devil) among fishermen.
These chromatophores ( which are of different size and belong to more than one set) may rapidly cycle through colours other than white and red, flashing too quickly for the human eye to see the transitions. They have a short lifespan of about 1 to 2 years.
They are mostly found at depths of 660 – 2,300 ft (200 – 700 m), from Tierra del Feugo to California. This species is spreading north into waters of the Pacific Northwest, Washington, Oregon, Alaska, British Columbia. They are fished commercially in Peru and Mexico.
The Humboldt squid is the largest known member of the Ommastrephids squids, as some individuals may grow to 8 ft 2 in (2.5 m) in mantle length and weigh up to 100 lb (50 kg).
Generally, the body (or mantle) constitutes about 40% of the animal’s mass, wings (or fins) about 12%, the tentacles and arms about 14%, the head (including beak and eyes) about 5%, the outer skin about 3%, with the remaining 26% made up of the inner organs.
The Humboldt squid’s diet consists mainly of crustaceans, small fish, copepods, cephalopods. The squid makes use of its barbed tentacle suckers to grab its prey and tears and slices the victim’s flesh with its radula and beak.
They attack preys with all 10 appendages extended forward in a cone-like shape. After reaching striking distance, they open their eight grasping and swimming arms and extend two long tentacles covered with sharp teeth. It grabs its prey and pulls it back towards a parrot-like beak, which can cause serious lacerations to human flesh.
The two longer tentacles can reach and grab prey at full length and also retract so quickly that almost the entire action happened in one frame of a normal-speed video camera. Each of the squid’s suckers is covered with sharp teeth, and the beak can tear flesh. Nevertheless, they are believed to lack the jaw strength to crack heavy bone.
The Humboldt squid also hunts by pulling its prey into great depths until the prey faints. The Humboldt squid also can devour larger prey when hunting in groups quickly.
Humboldt squid is known as carnivorous marine invertebrates that move in shoals of about 1,200 individuals. They swim at speeds up to 15mph (24 km/h; 13kn) propelled by two triangular fins and by water ejected through a hyponome (siphon).
Their tentacles bear 100 to 200 suckers, each lined with razor-sharp teeth, which it uses to grasp prey a drag it towards its large sharp beak.
Some research assumed that Humboldt squid is quite passive but are only aggressive while feeding. They often display signs of cannibalism as they are seen to attack vulnerable and injured squid of their own shoal readily.
Some researchers claim that the aggression displayed by the Humboldt squid is due to the reflective gear or flashing lights.
They dive to depths of 430 to 660 ft (130 to 200 m) below the surface to feed (up from their typical 2,300 ft (700 m) diving deep, beyond the range of human diving). They frequently attack deep-sea cameras and rendered them inoperable.
Female squids lay an almost transparent gelatinous egg masses and float freely in the water column. The size of egg mass varies on the size of the female that laid it.
Large Humboldt squid females can lay egg masses up to 3 to 4 m in diameter, while female squid lay egg masses of about 1 m in diameter. Egg masses are assumed to contain 5,000 – 4.1 million eggs, depending on the size of the female.
The Humboldt squid inhabits depth of 660 – 2,300 ft (200 – 700 m) in the eastern Pacific (Peru, Chile), ranging from Tierra del Fuego north to California. Its name was derived from the Humboldt Current, in which it lives, off the coast of South America.
Recently, the Humboldt squid having been occurring farther north, as far as British Columbia. The Humboldt squids prefer deep water, between 1,000 – 1,500, but cases of squids being washed up on shore at the Long Beach Peninsula in southwest Washington were reported in late 2004.
Humboldt squid was given the nickname jumbo squid because of their sheer size. They grow up to 6 feet (2 meters) and weigh as much as 110 pounds (50 kilograms). Humboldt squid is not the largest squid species.
Though the largest squids are Colossal and Giant squid, the giant squid grows up to 43 feet (13 meters) and weighs as much as 610 pounds (275 kilograms). In comparison, the Colossal squid grows up to 46 feet (14 meters) and weighs as much as 1,091 pounds (495 kilograms).