---
title: "What the sources say about the Giant Pacific Octopus | AnimalTracks.wiki"
description: "49 claims from the Giant Pacific Octopus profile, each beside the words of the source that backs it."
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---

# What the sources say about the Giant Pacific Octopus (*Enteroctopus dofleini*)

> 49 claims from the Giant Pacific Octopus profile, each beside the words of the source that backs it. A "..." marks a cut in a quote and [brackets] an insertion.

Profile: [Giant Pacific Octopus](https://animaltracks.wiki/animals/giant-pacific-octopus/)

## Giant Pacific Octopus (Enteroctopus dofleini) Species Profile. Alaska Department of Fish and Game.

https://www.adfg.alaska.gov/index.cfm?adfg=giantpacificoctopus.main

| The page says | The source says |
| :--- | :--- |
| Three brains, three hearts, blue copper blood | The Giant Pacific Octopus has eight arms, three brains and three hearts ... The Giant Pacific Octopus is known for having blue blood due to a copper-rich protein called hemocyanin |
| skin that changes color and texture | layered chromatophores (pigment cells) that enable it to change color. Like many octopus species E. dofleini also has the ability to change the texture of its skin |
| from southern Baja California to Alaska, the Aleutians, and Japan | Giant Pacific Octopus ranges throughout temperate waters of the Pacific Ocean (ranging south from southern Baja California and north to Alaska, west to the Aleutian Islands and then south again to Japan) |
| Shrimp, crabs, scallops, clams, lobster, fish, and soft-bodied prey | its diet includes shrimp, crab, scallop, clam, lobster, fish, and soft bodied prey |
| Three hearts, blue copper-rich blood | three brains and three hearts ... blue blood due to a copper-rich protein called hemocyanin |
| about 2,140 to 2,240 suckers that grip, taste, and smell | approximately 2,140 to 2,240 suction cups on their arms, giving them a powerful grip and a sense of taste and smell |
| a body that can squeeze through any hole large enough for its beak | An octopus can squeeze through any hole large enough to accommodate its beak |
| is the largest octopus species in the world | the Giant Pacific Octopus is the largest octopus species in the world |
| It weighs 22 to 110 pounds, averaging 45 to 65, though Canadian researchers once recorded one at 156 pounds, and it reaches that weight in about five years | The Giant Pacific Octopus weighs 22 to 110 pounds (avg. 45-65 pounds). A 156-pound animal was recorded by Canadian researchers. They have a relatively short lifespan and achieve this weight in about five years |
| Its whole life is thought to last just 3 to 5 years | The lifespan of E. dofleini is thought to be 3-to-5-years |
| It ranges through temperate Pacific waters, from southern Baja California north to Alaska, west to the Aleutian Islands and south again to Japan | ranges throughout temperate waters of the Pacific Ocean (ranging south from southern Baja California and north to Alaska, west to the Aleutian Islands and then south again to Japan) |
| It spends most of its life alone | The Giant Pacific Octopus spends most of its life in solitude |
| Shells from its meals pile up outside the den as a midden | Shells and debris from feeding accumulate on the sea floor outside dens and divers can sometimes locate dens by these middens |
| Two of its three hearts pump blood to its gills, and the third pumps it to the rest of the body | three hearts (two hearts pump blood to the gills and the third circulates blood to the rest of the body) |
| That blood is blue, from a copper-rich protein called hemocyanin | known for having blue blood due to a copper-rich protein called hemocyanin in their bloodstream |
| It has three brains, too | The Giant Pacific Octopus has eight arms, three brains and three hearts |
| An adult's eight arms carry about 2,140 to 2,240 suckers, which give it a powerful grip and a sense of taste and smell | The adult Giant Pacific Octopus has approximately 2,140 to 2,240 suction cups on their arms, giving them a powerful grip and a sense of taste and smell (note: Oceana says 'hundreds of tasting suckers'; ADFG's count is the specific adult figure and is attributed to adults as ADFG scopes it.) |
| Its parrot-like beak is the only hard part of its body, and it can squeeze through any hole large enough for that beak: a 50-pound octopus can fit through a two-inch hole | Their parrot-like beak is made of keratin and is the only hard part of their body. An octopus can squeeze through any hole large enough to accommodate its beak - A 50-pound octopus can fit through a two-inch hole |
| Its suction discs are quite effective, and Alaska's state wildlife agency notes that octopuses have been able to unscrew jar lids from inside the jar | The suction discs on the arms are quite effective and octopus have been able to unscrew the lids of jars - from inside the jar (note: ADFG does not say these octopuses were captive, so the page does not add it.) |
| Layered pigment cells called chromatophores let it shift between pale grey and dark red, and it can also change the texture of its skin to blend into its surroundings | The Giant Pacific can be pale grey to dark red depending on the use of the layered chromatophores (pigment cells) that enable it to change color. Like many octopus species E. dofleini also has the ability to change the texture of its skin allowing it to blend into structural components of the environment |
| Built to Vanish | their ability to change color and texture of their skin (seemingly disappearing) (note: Blockquote label.) |
| males die a few weeks after mating | The males pass a spermatophore into the female's mantle during mating, he dies a few weeks later |
| About 40 days after mating, a female finds a rocky den and lays up to 100,000 eggs in long strands | About 40 days after mating, the female will find a rocky den and lay up to 100,000 eggs in long strands |
| She guards and cleans them without eating and slowly starves, dying around the time they hatch | The female stays with the eggs, guarding them from predators, keeping them clean ... The female fasts while attending to her eggs and slowly starves, she dies about the same time the eggs hatch (note: ADFG's 'up to six months' of guarding is left out: Oceana says hatching can take up to a year.) |
| Its short life and reclusive nature also make it hard to study | The short life span combined with the reclusive nature of this species makes research difficult |
| Three of each, alongside its eight arms. Two of its hearts pump blood to the gills, and the third pumps it to the rest of the body. | The Giant Pacific Octopus has eight arms, three brains and three hearts (two hearts pump blood to the gills and the third circulates blood to the rest of the body) |
| Its blood is blue because of hemocyanin, a copper-rich protein in its bloodstream. | The Giant Pacific Octopus is known for having blue blood due to a copper-rich protein called hemocyanin in their bloodstream |
| Its parrot-like beak is the only hard part of its body, and it can squeeze through any hole large enough for that beak. Alaska's state wildlife agency says a 50-pound octopus can fit through a hole two inches across. | Their parrot-like beak is made of keratin and is the only hard part of their body. An octopus can squeeze through any hole large enough to accommodate its beak - A 50-pound octopus can fit through a two-inch hole |
| Its suction discs are quite effective too: octopuses have been able to unscrew jar lids from inside the jar. | The suction discs on the arms are quite effective and octopus have been able to unscrew the lids of jars - from inside the jar |
| A Giant on a Five-Year Clock | the largest octopus species in the world ... achieve this weight in about five years (note: Heading.) |
| Three Hearts and No Bones | Their parrot-like beak is made of keratin and is the only hard part of their body (note: Heading. The three hearts are claimed in the section's first sentence.) |
| A Short, Strange Life | They have a relatively short lifespan (note: Heading.) |
| Shape-shifting experimental electronics for an octopus with three brains | The Giant Pacific Octopus has eight arms, three brains and three hearts (note: vibe.reason (task #445); replaces the unsourced '9-brain' clause) |
| whose layered pigment cells shift its skin between pale grey and dark red | The Giant Pacific can be pale grey to dark red depending on the use of the layered chromatophores (pigment cells) that enable it to change color (note: vibe.reason (task #445)) |
| weightKg: 25 | The Giant Pacific Octopus weighs 22 to 110 pounds (avg. 45-65 pounds) (note: task #445; 45 to 65 lb is 20 to 29 kg, 25 kg is the midpoint. ADW's 'average weight of 60 kg' is not used: it contradicts ADFG and ADW is the weaker source for a figure) |

## Enteroctopus dofleini (giant Pacific octopus). Animal Diversity Web, University of Michigan.

https://animaldiversity.org/accounts/Enteroctopus_dofleini/

| The page says | The source says |
| :--- | :--- |
| dangerLevel: Low | There are no known adverse effects of giant Pacific octopuses on humans (note: task #445; ADW also: 'timid and rarely display aggressive behavior toward humans unless challenged') |

## Giant Pacific Octopus. Oceana Marine Life Encyclopedia.

https://oceana.org/marine-life/cephalopods-crustaceans-other-shellfish/giant-pacific-octopus

| The page says | The source says |
| :--- | :--- |
| Kelp fields, dens, and crevices across the temperate North Pacific | Giant pacific octopuses are found in the North Pacific Ocean ... They are often found in fields of kelp and dwell in dens and crevices |
| Its arms can span up to 31 feet across | arms that can span up to 9. 5 meters (31 feet) across (note: ADFG's 'arm length can span up to 16 feet' is ambiguous (one arm or the span) and is not used, so the page gives a single span figure.) |
| It is generally found from shallow tide pools down to 110 meters (361 feet), though it has turned up more than 1,500 meters (4,921 feet) down | generally found along the coast in shallow tidal pools to depths of 110 m eters (360.9 feet) , but they have also been found over 1,500 meters (4,921.3 feet) b elow the surface (note: 360.9 feet rounds to 361; Oceana's 4,921.3 feet is its own conversion of 1,500 meters.) |
| often in kelp fields, sheltering in dens and crevices floored with sand, mud or gravel | They are often found in fields of kelp and dwell in dens and crevices with soft ground made of sand, mud, or gravel |
| Its diet is mostly clams, crabs, fish and squid | their diet primarily composed of clams, crabs, fish, and squid |
| Females mate only once in their lives | females mate only once in their lifetime |
| Oceana says scientists believe its numbers are stable, but little is known about its overall population size | while scientists believe their numbers are stable, little is known about their overall population size |

## Anderson et al. (2010). Octopuses ( Enteroctopus dofleini ) Recognize Individual Humans. Journal of Applied Animal Welfare Science.

https://doi.org/10.1080/10888705.2010.483892

| The page says | The source says |
| :--- | :--- |
| In another, eight octopuses were each exposed to two unfamiliar people, one who fed them and one who touched them with a bristly stick. After two weeks they showed a different body pattern and reached their arms differently toward each person, and the four larger ones changed how fast they breathed | This study exposed 8 Enteroctopus dofleini separately to 2 unfamiliar individual humans over a 2-week period under differing circumstances. One person consistently fed the octopuses and the other touched them with a bristly stick ... At the end of 2 weeks, a body pattern (a dark Eyebar) and 2 behaviors (reaching arms toward or away from the tester and funnel direction) were significantly different in response to the 2 humans. The respiration rate of the 4 larger octopuses changed significantly |
| In one study, eight octopuses were each exposed to two unfamiliar people over two weeks: one fed them and the other touched them with a bristly stick. By the end, the octopuses showed a different body pattern and reached their arms toward or away from each person differently, and the four larger ones changed their breathing rate. The researchers took this as evidence that octopuses can recognize individual humans. | This study exposed 8 Enteroctopus dofleini separately to 2 unfamiliar individual humans over a 2-week period under differing circumstances. One person consistently fed the octopuses and the other touched them with a bristly stick ... a body pattern (a dark Eyebar) and 2 behaviors (reaching arms toward or away from the tester and funnel direction) were significantly different in response to the 2 humans. The respiration rate of the 4 larger octopuses changed significantly ... Octopuses' ability to recognize humans |

## Holst et al. (2022). Behavioral changes in senescent giant Pacific octopus (Enteroctopus dofleini) are associated with peripheral neural degeneration and loss of epithelial tissue. Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology.

https://doi.org/10.1016/j.cbpa.2022.111263

| The page says | The source says |
| :--- | :--- |
| Most octopus species go through extreme physical decline after a single breeding bout | Most species of octopus experience extreme physical decline after a single reproductive bout |
| In giant Pacific octopuses kept in US public aquariums, researchers found that this decline, called senescence, changes how they respond to light touch and painful stimuli, and that the arm tips of terminally senescent animals had a lower density of nerve and skin cells than those of healthy octopuses that had not yet bred | giant Pacific octopus (GPO), Enteroctopus dofleini, held in public aquariums in the USA. Post-euthanasia, tissue was collected from arm tips ... compared with biopsies of arm tips from healthy, pre-reproductive GPOs. Behavioral assays showed significant changes both in low threshold mechanosensory responses and nociceptive behavioral responses beginning early in senescence ... overall neural and epithelial cell density was significantly lower in terminally senescent octopuses compared with healthy controls |

## Anderson & Mather (2007). The packaging problem: Bivalve prey selection and prey entry techniques of the octopus Enteroctopus dofleini. Journal of Comparative Psychology.

https://doi.org/10.1037/0735-7036.121.3.300

| The page says | The source says |
| :--- | :--- |
| In one study, it pulled apart mussels and Manila clams, the thinnest-shelled prey on offer, but got into littleneck clams by chipping the shell or drilling through it, presumably to inject a toxin | When given prey of mussels Mytilus trossulus, Manila clams Venerupis philippinarum, and littleneck clams Protothaca staminea ... They pulled apart V. philippinarum and M. trossulus, which had the thinnest shells and the least pulling resistance. P. staminea were eaten after the shells had been chipped or had been penetrated by drilling, presumably to inject a toxin |

## Allcock, Taite & Allen (2018). Enteroctopus dofleini. The IUCN Red List of Threatened Species 2018: e.T162958A958049.

https://doi.org/10.2305/iucn.uk.2018-2.rlts.t162958a958049.en

| The page says | The source says |
| :--- | :--- |
| The IUCN rates the species Least Concern | IUCN Red List category: Least Concern (LC). Enteroctopus dofleini (Wülker, 1910), IUCN taxon 162958. (note: Category read through GBIF's copy of the Red List; Oceana's current page agrees ('currently listed as Least Concern by the IUCN Red List').) |