The Humbolt squid (Dosidicus gigas), also known as the jumbo flying squid, is a large predator native to the eastern pacific oceans mesopelagic zone. They can have a mantle length of up to 1.5m. With a maximum weight of 50kg, it is the largest squid within its family. They are most commonly found at depths between 200-700 meters.

The Humbolt squid has a large mantle, making up most of its body. The mantle has two triangular fins, which it employs for swimming, in addition to a siphon which it can eject water out of to propel itself forward.

A Humbolt squid at a depth of 250m. Note the siphon under the mantle, which it uses for jet propulsion.

A Humbolt squid at a depth of 250m. Note the siphon under the mantle, which it uses for jet propulsion. Credit: Rick Starr NOAA/CBNMS

Like all other squids, the Humbolt squid has 10 tentacles. Two of these tentacles are modified Рbeing long and outfitted with sharp barbs and hooks, to grab their prey with. After grabbing hold of a prey,  they retract their arms Рpulling the prey towards their sharp and beak-like mouth. The motion of lashing out with their tentacles and pulling the prey back to its mouth can happen faster than a second! Their prey includes lanternfish, krill, and even individuals of their own species when food is scarce!

3D model of a Humbolt squid with two arms extended and the other eight tentacles open – ready to strike unsuspecting prey!

The humbolt squid participates in the worlds largest migration in terms of biomass, happening every single day. This is known as diel vertical migration, and involves swimming closer to the surface water during nighttime to feed, and down to the dark depths of the mesopelagic zone during daytime to hide from predators. In addition, they can hunt in extremely large groups of thousands of individuals – resembling a feeding frenzy in the deep sea.

They have photophores (organs that produce bioluminescense!), just like lanternfish, but unlike most mesopelagic organisms with photophores on the surface of their bodies, the Humbolt squid has photophores under their skin! In addition to this, they possess cromatophores which are specialized organs that allow them to change the colour of their bodies, and produce different patterns on their skin, just like a chameleon! Recent studies have found that Humbolt squid likely communicate with other individuals during hunting, with both photophores and chromatophores!  (1)

Large group of Humbolt squid filmed from an ROV while hunting mesopelagic fish. Credit: MBARI (2009)

With their advanced hunting behaviour, large body, and ferocious appetite, the Humbolt squid are efficient predators in the marine environment, and an important part of the mesopelagic food web.

Are you interested in learning more about different mesopelagic organisms? Check out our latest video below!