Octopuses & other Cephalopods 



Octopuses belong to the class of marine molluscs known as the Cephalopoda.

Cephalopoda contains the nautiluses; cuttlefishes, squids, and octopuses.

1)  They are the most advanced of all the invertebrates.
2)  They move by jet propulsion, squirting water from a funnel.
3)  They are the most intelligent of the invertebrates, with a capacity for learning.
4)  Most of them are able to eject ink to confuse predators.
5)  Most of them have a remarkable ability to change colour.
6)  They have arms with suckers which they use to capture prey. (Octopuses have eight arms, squids have ten).
7)  They have a hard beak to tackle prey with hard shells like crabs.
8)  Their heyday was 100 million years ago in Cretaceous times when Ammonites were plentiful in the oceans of Earth.
9)  Although they are molluscs, most of them have evolved to have only a diminished internal shell (the cuttlebone of the cuttlefish), or have lost their shell completely (octopus).
10) The Giant Squid, Architeuthis, is the largest invertebrate known, and stretched out with its tentacles included, it has attained 18 metres in length. Even larger specimens may await to be discovered in the deepest oceans.
 



 

Curled Octopus (Photograph by Peter Tannett)

Curled Octopus  Eledone cirrhosa



 

3 Match 2008
hexapus, or six-legged version of the Lesser or Curled Octopus, Eledone cirrhosa, was captured in a lobster pot off the coast of north Wales and put on show at the Anglesey Sea Zoo. It was only then it was discovered to have only six legs instead of the normal eight, and this may have a result of a birth defect rather than an accident. It was been claimed as a world's first as nobody seems to discovered one before. Its fame meant it was transferred to the Blackpool Sea Life Centre to attract a bigger audience.

BBC News Report (2)
BBC News Report (1)
Yahoo News Report

16 January 2008
A Lesser or Curled Octopus, Eledone cirrhosa, was caught off Anglesey on rod and line in 40 ft of water, 50 metres or so from the shore at mid-tide. It was caught on dead fish bait for Whiting and Codling. It was slightly smaller than the size of a fist.

Report by Andrew Caine (Warrington)

October 2005

Lesser Octopus (Photograph by Roger Young)

In Saundersfoot, south Wales we found a Lesser or Curled Octopus, Eledone cirrhosa. It was very much alive and although stranded by the receding tide, when placed in a nearby deep rock pool where it became quite active, changing colour.

 Report by Roger M Young


21 March 2002
About twenty dead Lesser Octopuses, Eledone cirrhosa, were scattered over a stretch of about 200 metres of  Killiney beach, Co. Kerry, Ireland. The tentacles/arms were about 15 cm long.

Report by Leo Dungan sent in by Jim Wilson (University of Dublin)

 

Curled Octopus (Photograph by Helen Nott)

17 November 2001
A Curled Octopus was discovered by Helen Nott on Heacham Beach, Norfolk, In this clear photograph, you can see the single row of suckers. The Common Octopus has a double row.

15 October 2000
A Curled Octopus over 1 kg in weight was caught off Roker Pier, near Sunderland, NE England.

15 May 1999
 Dr Peter Tannett discovered the photographed Curled Octopus whilst on a field meeting with the Yorkshire Naturalists' Union on rocks just above low water at Ravenscar, North-east Yorkshire on Saturday 15 May 1999.



18 November 2002
The same fisherman who caught the Common Octopus, Octopus vulgaris, on 30 October 2002 caught an even larger one, which weighed in at  6740 grams.  It was captured alive and placed in the Guernsey Aquarium but it failed to survive.
 
Photograph by Richard Lord (Copyright protected throughout the World)
 
                                          Common Octopus
                                         Photograph  ©  by Richard Lord (Guernsey)
Dr. Daniel Latrouite (IFREMER Centre de Brest) wrote:
Octopus vulgaris which had disappeared from French-English Channel and north of Biscay Bay after February 1963 are effectively re-expanding in these areas. Since 4 or 5 years potters from south Brittany and west Brittany (Le Conquet) catch more and more octopuses, often very big, and can find their pots de-baited. North Brittany: a potter from Plougasnou told me his octopus landings
were about 20 kg last year and over 300 kg this year (March to August). Octopus vulgaris is clearly a predator on lobster and spider crabs.
Report by Richard Lord (Guernsey)
via the Marine Wildlife of the North-east Atlantic Ocean Group


Three Common Octopuses were also reported from Cornwall during the first weeks of November 2002.

Report from Stella Turk on the Cornish Mailing List
30 October 2002
A Common Octopus, Octopus vulgaris, was caught this morning in a crab pot to the south-east of St. Martin's Point, Guernsey.
The live octopus will be weighed and measured and taken to the Guernsey Aquarium.
The male Octopus vulgaris caught on the morning of October 30 off the south-east coast of Guernsey died overnight.  It was missing left arm two.  It weighed 5010 grams and had a total length of 91 cm.  Mantle length was 21 cm.  The beak to the tip of left arm four measured 71 cm.
I have heard that Octopus vulgaris is causing losses in the Bay of Biscay crab fishery this year.
Report by Richard Lord (Guernsey)
via the Marine Wildlife of the North-east Atlantic Ocean Group


4 October 2002
A Guernsey fisherman caught a large Common Octopus, Octopus vulgaris, in a crab pot about half a mile from Hanois Lighthouse off the south-western tip of Guernsey.  The octopus had devoured at least two edible crabs and one lobster.  The fisherman estimated the total length at about 1.5 metres and the tentacle length at 1 metre.  He estimated the weight at 4.5 to 5.5 kg (10 to 12 lb).  He returned the octopus to the sea.
Another Guernsey fisherman caught a large Octopus vulgaris in July 2002.
Sea surface temperatures at the entrance to St. Peter Port harbour, Guernsey have been about 1.5° C warmer since early August than the average sea surface temperature for the last 20 years.  The sea at the entrance to St. Peter Port harbour has been warmer in every week this year than the average temperature for the past twenty years. The highest sea temperaure occurred on 2 October 2002 at 17.8° C compared to the mean of 16.7° C.

Report by Richard Lord (Guernsey)
via the Marine Wildlife of the North-east Atlantic Ocean Group


13 August 2002
One large Octopus vulgaris was caught south of Plymouth and landed on the Plymouth Fish Market.
 

May 2002
A Common Octopus, Octopus vulgaris, was caught three quarters of a mile at Chapel Point off Mevagissey, Cornwall, and presented to Mevagissey Harbour Marine Aquarium.

Report by Chris Gilbertson (Mevagissey Harbour Aquarium)


25 March 2002
A Common Octopus, Octopus vulgaris, in Plymouth Fish Market. This one was not notified, so maybe they are getting commoner in the seas off the south-west?

Two Reports by Doug Herdson. (National Marine Aquarium at Plymouth).
via the Marine Wildlife of the North-east Atlantic Ocean Group


31 October 2001
Fisherman Steve Long caught a Common Octopus, Octopus vulgaris, off the Cornish coast off Coverack in deepish water at about 75 metres (40 fathoms). This warm water octopus is now only rarely discovered in the English Channel, although within just about living memory it was commoner. This species was identified by Paul Gainey and it will go to the Blue Reef Aquarium in Newquay.

Report by Stella Turk via the Cornish Wildlife Mailing List


October 1998
 

                             A large Common Octopus, Octopus vulgaris, was brought into Plymouth Aquarium. It
                             was believed to have been caught off the extreme south-west of Cornwall. The
                             Common Octopus has been rare in British seas for nearly 40 years, apparently since the
                             cold winter of 1963.
                             The Looe boats also brought in a Squid measuring over 2 metres from the beak to the
                             tail, excluding the tentacles. The species was not identified. (Jon Makeham Report).
 

25 June 1999
A Common Octopus, Octopus vulgaris, was seen by a diver off off Dodman, Cornwall (SX 0039). It was a metre across. Common Octopuses are only rarely discovered even off the south-western coasts. However, in the past, before the cold winter of 1963, they may have been commoner.

Discovery Report by Doug Herdson. (National Marine Aquarium at Plymouth).
Notes by Andy Horton.
On Monday, November 16, 1998 two Guernsey fishermen found Octopus vulgaris in one of their pots along with one Edible Crab.  The pot was fishing about ten miles south of St. Martin's Point, Guernsey.  The fishermen estimated the Octopus at about 20 lb. and three feet long.  They told me it definitely had two rows of suckers.

On February 2, 1999 I picked up a specimen of Octopus vulgaris from a local crab fisherman who was potting a few miles south-east of Guernsey. The octopus weighed 4051 grams but Right arm III and IV were missing part of their length and Left arm I, II, III, & IV were missing part or all of their length.  Total length of octopus to tip of right arm I was 129 cm.

These are the only two Octopus vulgaris I have come across during my 6 years in Guernsey although there may have been a couple of other local captures.

Report by Richard Lord (Guernsey)
More Information (John Liddiard External Site)

CephBase Octopus vulgaris
 

Squid Eggs masses (Sussex coast)
Cornish Marine Wildlife Reports 1999 (by Ray Dennis)
Cornish Marine Wildlife Reports 2000 (by Ray Dennis)
Cornish Marine Wildlife Reports  2001 (by Ray Dennis)



Largest British Squids

3 January 2002
A deep water trawler after Blue Ling and Hake etc. caught a female Giant Squid, Architeuthis dux, amongst the large haul of fish. With a mantle length of 127 cm it is a medium-sized specimen with some of the tentacles missing. Therefore, the total length could not be measured, but it is estimated to be about 5.5 metres with a weight of about 60 kg. the specimen will be prepared for display at the National Marine Aquarium, Plymouth, ‘Creatures of the Deep' zone from May 2002.
This is believed to be the 25th Architeuthis recorded in British waters since 1673.  Fifteen have been stranded on the shores of the British Isles, nine caught in fishing gear and one found in the stomach of a Sperm Whale.

Report from Doug Herdson (National Marine Aquarium, Plymouth)
via the Marine Wildlife of the North-east Atlantic Ocean Group
Giant Squid:  Full Report
Aberdeen University Giant Squid site (by Dr Martin Collins)

There have been nineteen species of Architeuthis described but it is unlikely that there are more than seven, and most recent work suggests that there are three species - Architeuthis dux in the north Atlantic, Architeuthis martensi or japonica in the northern Pacific and Architeuthis sanctipauli in the Southern Ocean.  However DNA studies have so far been carried out on only two specimens, one from New Zealand and one from Newfoundland (Atlantic coast of Canada), and the results so far published show no significant differences between them.

According to the Guinness Book of Records 1991, the largest squid found in British seas was an Architeuthis monachus found at the head of Whalefirth Voe, Shetland Isles on 2 October 1959. Its total length was measured at 7.31 metres (24 ft).

However, details of this record may be called into question as it is included in the List of British & Irish Strandings in year 1949 with a mantle length of 1.2 metres.
On this list the largest measured specimen had a mantle length of 1.75 metres and was stranded in Cove Bay, Aberdeen on 8 January 1984. (My estimate of the total length would be nearer 6.7 metres or 22 ft.)

The world's largest species is Architeuthis dux.



Molluscs Page



Octopuses is the correct plural in English (UK) as both the prefix and the suffix are Greek. However, John Steinbeck uses octopi so in English (American) the alternative could be used.

Architeuthis: News Report
Architeuthis: the Giant Squid
CephBase
Full Report (Aberdeen University)
EuroSquid
 
 

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