At Axial Seamount, there are two common species of octopus, and at least one squid. These taxa all belong to Phylum Mollusca, Class Cephalopoda.
The largest octopus observed at Axial Seamount, Graneledone pacifica, is very curious and fairly common on the lava rocks and at hydrothermal vent fields. It is not unique to Axial, as it is found in other Pacific deep sea environments. At Axial, these octopods seem to be attracted to the abundant vent fauna on which they prey. The octopus may also use the hard lava rock substrate found at Axial for laying their eggs.
Specimens off the Oregon coast have been measured at 43 cm (17 in), though Axial specimens are estimated at less than 40 cm.
(Contributed by Katie Bigham, University of Washington, VISIONS 14, Leg 1)
Grimpoteuthis is a genus of octopus species called Dumbo Octopuses. They are named for the large, ear-like fins on the sides of their heads, which are used for swimming through the water column. Not having the ability to chew their food, the octopuses are forced to hunt small prey, which can include crustaceans, bivalves, and worms. Living an average of 3 to 5 years, at depths up to 7 km, these are some of the deepest-living species of octopus in the world. Various species of Dumbo Octopus can be found worldwide, including Axial Seamount, where this small, pink variety has been observed on several occasions. Most species of Dumbo Octopus grow to be about 20-30 cm in length, although examples have been found that measured ~1.8 m. (Contributed by Katie Bigham, University of Washington, V14, Leg 1)
The Cockatoo Squid is a deep sea member of the glass squids, found in the waters above Axial Seamount. These squid have sac-like bodies filled with ammonia to aid in their buoyancy. They also have a mass of tentacles above their heads that resemble a cocatiel's crest, the basis of this squid’s common name. The Cockatoo Squid has large eyes that are capable of moving from a forward looking direction to either side of its head. Special light-emitting cells called photophores located under their eyes help the squid to be camouflaged by canceling out its shadows. Cockatoo Squid can grow to 50cm (19.7in). (Contributed by Katie Bigham, University of Washington, VISIONS 14, Leg 1)