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What the sources say

Giant Pacific OctopusEnteroctopus dofleini

Every figure, record and mechanism on the Giant Pacific Octopus profile was written from a source, and this is the working table behind it: 49 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

Alaska Department of Fish and Game

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

The page saysThree brains, three hearts, blue copper blood
The source saysThe 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
The page saysskin that changes color and texture
The source sayslayered 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
The page saysfrom southern Baja California to Alaska, the Aleutians, and Japan
The source saysGiant 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)
The page saysShrimp, crabs, scallops, clams, lobster, fish, and soft-bodied prey
The source saysits diet includes shrimp, crab, scallop, clam, lobster, fish, and soft bodied prey
The page saysThree hearts, blue copper-rich blood
The source saysthree brains and three hearts ... blue blood due to a copper-rich protein called hemocyanin
The page saysabout 2,140 to 2,240 suckers that grip, taste, and smell
The source saysapproximately 2,140 to 2,240 suction cups on their arms, giving them a powerful grip and a sense of taste and smell
The page saysa body that can squeeze through any hole large enough for its beak
The source saysAn octopus can squeeze through any hole large enough to accommodate its beak
The page saysis the largest octopus species in the world
The source saysthe Giant Pacific Octopus is the largest octopus species in the world
The page saysIt 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 source saysThe 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
The page saysIts whole life is thought to last just 3 to 5 years
The source saysThe lifespan of E. dofleini is thought to be 3-to-5-years
The page saysIt ranges through temperate Pacific waters, from southern Baja California north to Alaska, west to the Aleutian Islands and south again to Japan
The source saysranges 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)
The page saysIt spends most of its life alone
The source saysThe Giant Pacific Octopus spends most of its life in solitude
The page saysShells from its meals pile up outside the den as a midden
The source saysShells and debris from feeding accumulate on the sea floor outside dens and divers can sometimes locate dens by these middens
The page saysTwo of its three hearts pump blood to its gills, and the third pumps it to the rest of the body
The source saysthree hearts (two hearts pump blood to the gills and the third circulates blood to the rest of the body)
The page saysThat blood is blue, from a copper-rich protein called hemocyanin
The source saysknown for having blue blood due to a copper-rich protein called hemocyanin in their bloodstream
The page saysIt has three brains, too
The source saysThe Giant Pacific Octopus has eight arms, three brains and three hearts
The page saysAn 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 source saysThe 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 smellNote: Oceana says 'hundreds of tasting suckers'; ADFG's count is the specific adult figure and is attributed to adults as ADFG scopes it.
The page saysIts 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
The source saysTheir 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
The page saysIts 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 source saysThe suction discs on the arms are quite effective and octopus have been able to unscrew the lids of jars - from inside the jarNote: ADFG does not say these octopuses were captive, so the page does not add it.
The page saysLayered 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 source saysThe 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
The page saysBuilt to Vanish
The source saystheir ability to change color and texture of their skin (seemingly disappearing)Note: Blockquote label.
The page saysmales die a few weeks after mating
The source saysThe males pass a spermatophore into the female's mantle during mating, he dies a few weeks later
The page saysAbout 40 days after mating, a female finds a rocky den and lays up to 100,000 eggs in long strands
The source saysAbout 40 days after mating, the female will find a rocky den and lay up to 100,000 eggs in long strands
The page saysShe guards and cleans them without eating and slowly starves, dying around the time they hatch
The source saysThe 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 hatchNote: ADFG's 'up to six months' of guarding is left out: Oceana says hatching can take up to a year.
The page saysIts short life and reclusive nature also make it hard to study
The source saysThe short life span combined with the reclusive nature of this species makes research difficult
The page saysThree 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 source saysThe 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)
The page saysIts blood is blue because of hemocyanin, a copper-rich protein in its bloodstream.
The source saysThe Giant Pacific Octopus is known for having blue blood due to a copper-rich protein called hemocyanin in their bloodstream
The page saysIts 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.
The source saysTheir 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
The page saysIts suction discs are quite effective too: octopuses have been able to unscrew jar lids from inside the jar.
The source saysThe suction discs on the arms are quite effective and octopus have been able to unscrew the lids of jars - from inside the jar
The page saysA Giant on a Five-Year Clock
The source saysthe largest octopus species in the world ... achieve this weight in about five yearsNote: Heading.
The page saysThree Hearts and No Bones
The source saysTheir parrot-like beak is made of keratin and is the only hard part of their bodyNote: Heading. The three hearts are claimed in the section's first sentence.
The page saysA Short, Strange Life
The source saysThey have a relatively short lifespanNote: Heading.
The page saysShape-shifting experimental electronics for an octopus with three brains
The source saysThe Giant Pacific Octopus has eight arms, three brains and three heartsNote: vibe.reason (task #445); replaces the unsourced '9-brain' clause
The page sayswhose layered pigment cells shift its skin between pale grey and dark red
The source saysThe Giant Pacific can be pale grey to dark red depending on the use of the layered chromatophores (pigment cells) that enable it to change colorNote: vibe.reason (task #445)
The page saysweightKg: 25
The source saysThe 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

Source
02

Animal Diversity Web, University of Michigan

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

The page saysdangerLevel: Low
The source saysThere are no known adverse effects of giant Pacific octopuses on humansNote: task #445; ADW also: 'timid and rarely display aggressive behavior toward humans unless challenged'

Source
03

Oceana Marine Life Encyclopedia

Giant Pacific Octopus. Oceana Marine Life Encyclopedia.

The page saysKelp fields, dens, and crevices across the temperate North Pacific
The source saysGiant pacific octopuses are found in the North Pacific Ocean ... They are often found in fields of kelp and dwell in dens and crevices
The page saysIts arms can span up to 31 feet across
The source saysarms that can span up to 9. 5 meters (31 feet) acrossNote: 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.
The page saysIt 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
The source saysgenerally 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 surfaceNote: 360.9 feet rounds to 361; Oceana's 4,921.3 feet is its own conversion of 1,500 meters.
The page saysoften in kelp fields, sheltering in dens and crevices floored with sand, mud or gravel
The source saysThey are often found in fields of kelp and dwell in dens and crevices with soft ground made of sand, mud, or gravel
The page saysIts diet is mostly clams, crabs, fish and squid
The source saystheir diet primarily composed of clams, crabs, fish, and squid
The page saysFemales mate only once in their lives
The source saysfemales mate only once in their lifetime
The page saysOceana says scientists believe its numbers are stable, but little is known about its overall population size
The source sayswhile scientists believe their numbers are stable, little is known about their overall population size

Source
04

Anderson et al. 2010

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

The page saysIn 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
The source saysThis 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
The page saysIn 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.
The source saysThis 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

Source
05

Holst et al. 2022

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.

The page saysMost octopus species go through extreme physical decline after a single breeding bout
The source saysMost species of octopus experience extreme physical decline after a single reproductive bout
The page saysIn 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
The source saysgiant 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

Source
06

Anderson & Mather 2007

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

The page saysIn 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
The source saysWhen 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

Source
07

Allcock, Taite & Allen 2018

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

The page saysThe IUCN rates the species Least Concern
The source saysIUCN 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').

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.