Jump to content

Giant Pacific octopus: Difference between revisions

From Wikipedia, the free encyclopedia
Content deleted Content added
m rv; octopuses is correct
No edit summary
Line 1: Line 1:
{{Taxobox
{{Taxobox
| name = North Pacific Giant Octopus
| name = North Pacific Giant Octopus Does not Exist
| image = Enteroctopus dolfeini.jpg
| image = Enteroctopus dolfeini.jpg
| image_caption = ''E. dofleini'' observed off Pt Pinos at a depth of 65 meters.
| image_caption = ''E. dofleini'' observed off Pt Pinos at a depth of 65 meters.

Revision as of 09:39, 3 April 2010

North Pacific Giant Octopus Does not Exist
E. dofleini observed off Pt Pinos at a depth of 65 meters.
Scientific classification
Kingdom:
Phylum:
Class:
Order:
Family:
Genus:
Species:
E. dofleini
Binomial name
Enteroctopus dofleini
(Wülker, 1910)
Distribution of E. dofleini
Synonyms
  • Octopus punctatus
    Gabb, 1862
  • Octopus dofleini
    Wülker, 1910
  • Polypus dofleini
    Wülker, 1910
  • Octopus dofleini dofleini
    (Wülker, 1910)
  • Polypus apollyon
    Berry, 1912
  • Octopus dofleini apollyon
    (Berry, 1912)
  • Polypus gilbertianus
    Berry, 1912
  • Octopus gilbertianus
    Berry, 1912
  • Octopus apollyon
    (Berry, 1913)
  • Octopus madokai
    Berry, 1921
  • Paroctopus asper
    Akimushkin, 1963
  • Octopus dofleini martini
    Pickford, 1964

The North Pacific Giant Octopus (Enteroctopus dofleini) is a large cephalopod belonging to the genus Enteroctopus. It can be found in the coastal North Pacific, usually at a depth of around 65 meters (215 ft). It can, however, live in much shallower or much deeper waters. It is arguably the largest octopus species, based on a scientific record of a 71 kg (156.5 lb) individual weighed live.[1] The alternative contender is the Seven-arm Octopus based on a 61 kg (134 lb) carcass estimated to have a live mass of 75 kg (165 lb).[2][3] However, there are a number of questionable size records that would suggest E. dofleini is the largest of all octopus species by a considerable margin.[4]

Size and description

Close-up of E. dofleini showing the longitudinal folds on the body and the paddle-like papillae.

The North Pacific Giant Octopus, or the Giant Pacific Octopus, are distinguished from other species by their sheer size. Adults usually weigh around 15 kg (33 lb), with an arm span of up to 4.3 m (14 ft).[5] However, there are highly questionable records of specimens up to 272 kg (600 lb) in weight with a 9 m (30 ft) arm span.[6] The mantle of the octopus is spherical in shape and contains most of the animal's major organs. The skin of the octopus is somewhat smooth and by contracting or expanding tiny pigments, known as chromatophores, in its cells an octopus can change the color of its skin, giving it the ability to blend into the environment.

Diet

This species of octopus commonly preys upon shrimp, crabs, scallops, abalone, clams, and fish. Food is procured with its suckers and then crushed using its tough "beak" of chitin. They have also been observed in captivity catching Spiny dogfish (Squalus acanthias) of up to 3-4 feet in length.[7] Additionally, consumed carcasses of this same shark species have been found in Giant Pacific Octopus middens in the wild, providing strong evidence that these octopuses predate on sharks in their natural habitat. [8]

Predators

Marine mammals such as Harbor Seals, Sea Otters, and Sperm Whales depend upon the North Pacific Giant Octopus as a source of food. The octopus is also commercially fished in the United States.

Life span and reproduction

The North Pacific Giant Octopus is considered to be short-lived for an animal its size, with life spans that average only 3-5 years in the wild. To make up for its relatively short life span, the octopus is extremely prolific. It can lay up to 100,000 eggs which are intensively cared for by the females. Hatchlings are about the size of a grain of rice, and only a very few survive to adulthood.

During reproduction, the male octopus deposits a spermatophore (or sperm packet) more than 1 meter long. Large spermatophores are characteristic of octopuses in this genus.[4]

Conservation

Very little is known about the population of this solitary creature and the North Pacific Giant Octopus is not currently under the protection of CITES or the IUCN Red List.

See also

References

  1. ^ Cosgrove, J.A. 1987. Aspects of the Natural History of Octopus dofleini, the Giant Pacific Octopus. M.Sc. Thesis. Department of Biology, University of Victoria (Canada), 101 pp.
  2. ^ O'Shea, S. 2004. The giant octopus Haliphron atlanticus (Mollusca : Octopoda) in New Zealand waters. New Zealand Journal of Zoology 31(1): 7-13.
  3. ^ O'Shea, S. 2002. Haliphron atlanticus — a giant gelatinous octopus. Biodiversity Update 5: 1.
  4. ^ a b Norman, M. 2000. Cephalopods: A World Guide. Hackenheim, ConchBooks, p. 214.
  5. ^ Smithsonian National Zoological Park: Giant Pacific Octopus
  6. ^ High, W.L. 1976. The giant Pacific octopus. U.S. National Marine Fisheries Service, Marine Fisheries Review 38(9): 17-22.
  7. ^ http://video.google.com/videoplay?docid=-7004909622962894202
  8. ^ Walla Walla University Marine Invertebrates Key: Giant Pacific Octopus
  • "CephBase: Giant Pacific octopus". Archived from the original on 2005-08-17.
  • Video of a giant octopus catching a shark
  • Video of a giant pacific octopus in an aquarium