Caribbean Reef Octopus

Octopus briareus

The Caribbean reef octopus, with its iridescent blue and green skin, is easy for divers to spot at night time. However, prey aren’t so lucky– this octopus is a master of the nocturnal ambush.

This species can be a fearsome foe for small reef critters! It flares out its arms and webbing like a huge net, engulfing entire heads of coral and trapping the creatures in its “net.”

Size

2 ft long (60 cm)

Lifespan

10-12 months

Habitat

Shallow seas — coral reef, seagrass, rubble, sand

Diet

Crustaceans, fishes, bivalves, worms

Range

Tropical Atlantic Ocean & Caribbean Sea

Predators

Sharks & large bony fishes

superpower

Speedy Exit

It only takes 15 seconds for this octopus’s babies to fully hatch from their eggs!

SCIENTIFIC NAME: Octopus briareus

teal octopus briareus canvasing and foraging coral to feed

SIZE OF THE CARIBBEAN REEF OCTOPUS

This species is a moderately-sized with a mantle length to 120 mm and a total length 60 cm ( 2 ft). It often weighs around 1 kg (2 lbs) though there are reports of possible longer specimens weighing up to 1.5 kg (3 lbs). The arms are 4-6x the mantle length and there are two rows of large suckers on each arm.

Caribbean reef octopus looking for food

CARIBBEAN REEF OCTOPUS LIFESPAN

Like many octopuses, this species grows fast and has a short life span of just 10 to 12 months. Mother octopus lays 200-500 large eggs between 1-1.4 cm (0.5 inch) in length, arranged in clusters. The male dies in the month following fertilization. The eggs develop within 50-80 days into miniature adults ready for a benthic lifestyle as soon as they hatch! These mini caribbean reef octopus have a mantle length of 5.5 mm (0.2 in) and are ready to change color, use jet propulsion, crawl, and squirt ink!

They grow at a rapid rate, on average increasing their weight by 5% per day. Within 17 weeks they are able to reach around 75% of their adult size, males are sexually mature within 140 days and females within 150 days.

DISTRIBUTION

The species is found along the western Atlantic ocean including South Florida, Bahamas, southeastern Gulf of Mexico, Caribbean Sea to northern South America including the West Indies and off the coast Curaçao.

two caribbean reef octopuses mating

HABITAT

This is a shallow-water species typically associated with coral reefs with a depth range from 3 to 20 m (9-65 ft). It can also be found in seagrass, rubble and sandy bottom habitats. They tend to inhabit rocky or structured dens during the daytime making them very difficult to find.

DIET

Adults eat shrimps, bivalves, crabs, probably gastropods, the Caribbean spiny lobster (Panulirus argus) and occasionally polychaetes (worms).

Octopus briareus doesn’t overeat…must be nice! This octopus does not regulate its food intake, but has its food intake largely under control of two environmental factors: water temperature and prey abundance. In a study, octopuses doubled their food intake from 20C to 30C (68F-85F) water temperature and octopuses ate more crabs when offered. More crab? Yes, please!

Caribbean Reef Octopus escaping!

BODY PATTERNS AND BEHAVIORS

The Caribbean reef octopus has large prominent eyes and is one of the few octopuses that has a blue-green iridescent appearance when its chromatophores are retracted. This species has irregular red-brown mottling, which gives it a marbled pattern on its mantle and arm webbing. It also has regular red-brown transverse bands along the arms in some color patterns and it can be covered with small, round papillae.

The Caribbean reef octopus is a nocturnal species foraging at night amongst live coral and coral rubble. Its web is large, deep, and thin allowing it to envelope small coral heads within the ballooning web. This foraging behavior is known as the parachute attack.

For capturing spiny lobster, the octopus attacks by grasping the lobster’s carapace or long antennae. Ever heard the sound (aka stridulation) produced by a spiny lobster? This sound is produced by a specialized organ located at the base of the long 2nd antennae. This is a defense tactic (along with tailflip and spiny antennae) against predators like the Caribbean reef octopus!

Caribbean Reef Octopus Canvased on Coral

Messenger, J.B. (1963) Behavior of Young Octopus briareus Robson. Nature 197:1186-1187. DOI: 10.1038/1971186a0

Borer, K. (1971) Control of food intake in Octopus briareus Robson. Journal of Comparative and Physiological Psychology. 75:171-185.  ISSN: 0021-9940

Bouwma, P.E. and Herrnkind, W.F. (2009) Sound production in Caribbean spiny lobster Panulirus argus and its role in escape during predatory attack by Octopus briareus. New Zealand Journal of Marine and Freshwater Research 43:3-13.

Raising and Rearing Octopus briareus by Dr. James B. Wood, The Cephalopod Page (TCP), thecephalopodpage.org/rearing.php

Mohammed, Karen, 2015. Octopus briareus (Caribbean Reef Octopus), The Online Guide to the Animals of Trinidad and Tobago

Caribbean Reef Octopuses, Octopus briareus, The MarineBio Conservation Society – marinebio.org/species/caribbean-reef-octopuses/octopus-briareus

Jereb, P.; Roper, C.F.E.; Norman, M.D.; Julian K Finn (eds), Cephalopods of the world. An annotated and illustrated catalogue of cephalopod species known to date. Volume 3. Octopods and Vampire Squids. FAO Species Catalogue for Fishery Purposes. No. 4, Vol. 3. Rome, FAO. 2014. 370 p. 11 colour plates.

Lee, L. 2017. “Octopus briareus“, Animal Diversity Web.

Allcock, L. & Headlam, J. 2018. Octopus briareus. The IUCN Red List of Threatened Species 2018: e.T163175A980439. https://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T163175A980439.en

Caribbean Reef Octopus, Octopus briareus, CEPHALOPODS, CRUSTACEANS, & OTHER SHELLFISH, Oceana oceana.org/marine-life/cephalopods-crustaceans-other-shellfish/caribbean-reef-octopus

Octopus briareus Robson, 1929, Caribbean reef octopus, Palomares, M.L.D. and D. Pauly. Editors. 2019. SeaLifeBase, sealifebase.ca/summary/Octopus-briareus.html

view of a cockeyed squid in blue light with a glowing giant eye

Meet the Cockeyed Squid: the Deep-Sea Animal with a Giant Eye!

Get ready to meet the dazzling, one-of-a-kind Histioteuthis heteropsis, affectionately known as the “Cockeyed Squid” (because of it’s mismatched eyes) or “Strawberry Squid” ( cuz of its deep red pigmentation and photophores resembling strawberry seeds​) The species name “heteropsis” is derived from Greek, with “hetero” meaning ‘different’ and “opsis” meaning ‘sight’ or ‘eye’. Thus, “heteropsis”

Read More »

‘Cephalotography’ Of The Week: Jialing Cai

Dive into moonlit waters with OctoNation alongside Jialing Cai, an award winning underwater photographer from Chongqing, China, whose tales may just spark the beginning of your scuba adventure! Discover the challenges and joys of capturing the elusive octopus and other cephalopods. Ready? Let’s go! How long have you been an underwater photographer? How did you

Read More »

10 Facts About Baby Nautilus!

🔘 Googly eyed and barely bigger than a cherry 🍒 is how a baby nautilus bursts into the ocean scene to start its life. The nautilus is a hard-shelled cephalopod that has been around since long before dinosaurs, mammals, and insects, which means it once shared the ocean with the megalodon (the largest shark that

Read More »

Book Giveaway: The Lives of Octopuses and Their Relatives

🐙 🎉 OctoNation is beyond thrilled to offer our community a chance to win one of the newest octopus books to hit the shelves— and it’s a BIG ONE (nearly 300 pages!) Simply enter your name and email address to register & learn even more about the Lives of Octopuses and Their Relatives below! Book

Read More »

Do Octopus Bite?

Octopuses of myth and legend come off as monsters, but real-life octopuses are far from monstrous! Generally, octopuses aren’t interested in hurting humans unless humans are hurting them. And even though the answer to this question is yes, octopuses could bite you, you’ll soon learn that they usually won’t (unless you’re their prey, of course!)

Read More »
Skip to content