Hawaiian octopus (Octopus hawaiiensis)

Classification (WoRMS)

Full classification as recorded by WoRMS: Kingdom: Animalia · Phylum: Mollusca · Class: Cephalopoda · Order: Octopoda · Family: Octopodidae · Genus: Octopus.

Accepted name: Octopus hawaiiensis · Authority: Souleyet, 1852 · Taxonomic status: accepted · AphiaID: 535747.

Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=535747 (CC BY 4.0). Accessed 2026-09-23.

Biology and life history (SeaLifeBase)

Measured values published by SeaLifeBase for Octopus hawaiiensis. Only fields the database actually holds for this species are shown; these are database values, not aquarium guidance.

Maximum length: 3 cm · Depth range: 0–10 m · Habitat zone: benthic · Vulnerability index: 10 of 100 · Aquarium trade: never/rarely.

SeaLifeBase notes: Total length is more than 10 cm (Ref. 96968). Nocturnal predator using venoms or poisons to capture and kill prey. Mainly feeds on crabs and other mollusks and occasionally on fish (Ref. 122680).

Source: SeaLifeBase species summary (SpecCode 169200) — https://www.sealifebase.se/summary/Octopus-hawaiiensis.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-23.

Description and natural history (Wikipedia)

Octopus hawaiiensis is often confused with juvenile Octopus cyanea, but it can be distinguished by its smaller adult size and mottled reddish-brown coloration.

Octopus hawaiiensis was first described in 1914 by American malacologist Samuel Stillman Berry. It is classified within the family Octopodidae. The species has occasionally been confused taxonomically with unclassified or cryptic nearshore octopus species in Hawaiʻi, highlighting the need for continued phylogenetic research.'

Octopus hawaiiensis is characterized by a mottled reddish-brown coloration, which allows it to blend into rocky reef environments. It exhibits rapid chromatophore expansion and contraction, enabling dynamic camouflage similar to other members of Octopodidae. Adult individuals typically reach a mantle length of 15–20 cm, with proportionally long arms and a flexible skin texture that can shift between smooth and bumpy to match surrounding surfaces. The species is notably smaller than O. cyanea, with a more compact body shape and finer mottling patterns.

This species is endemic to the Hawaiian Islands and is most commonly observed in nearshore environments less than 30m deep. It inhabits reef flats, tide pools, sandy patches, and rocky crevices, where it can avoid predators and ambush prey. Its restricted range makes it an important indicator of nearshore ecosystem health.

Octopus hawaiiensis is a benthic predator, feeding primarily on small crustaceans, mollusks, and fish. Like other octopuses, it uses its arms and suckers to manipulate prey and its beak to break shells. It relies heavily on camouflage for both predation and defense, shifting skin color and texture to match its surroundings. Predators include larger reef fish, eels, and humans. Reproductive behavior is poorly documented, but it is presumed to involve egg deposition in protected crevices, followed by maternal brooding.

In Hawaiian culture, octopuses are known as he‘e. Octopus hawaiiensis is part of traditional subsistence fishing and is also taken recreationally. Octopuses hold cultural significance in Hawaiian mythology and are sometimes associated with shape-shifting legends and reef guardian spirits.

As of 2025, Octopus hawaiiensis has not been evaluated by the IUCN Red List. While no formal conservation measures are in place for this species specifically, it may benefit from broader nearshore fisheries regulations and habitat protection initiatives in Hawaiʻi. Potential threats include overharvesting, habitat degradation, and coastal development.

Source: Wikipedia: Octopus hawaiiensis — https://en.wikipedia.org/wiki/Octopus_hawaiiensis (CC BY-SA 4.0). Accessed 2026-09-23.