UNITED STATES DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE SERVICE BUREAU OF COMMERCIAL FISHERIES WASHINGTON 25, D.C. Fishery Leaflet 524 September 1961
CEPHALOPODS: Cuttlefish, Octopuses, Squids
By Lola T. Dees Branch of Reports Division of Resource Development
CONTENTS
Page
Introduction...... 1 Life history...... 1 Description...... 1 Food and feeding...... 2 Locomotion...... 2 Reproduction...... 2 Familiar cephalopods...... 3 Cuttlefish...... 3 Octopuses...... 4 Squids ...... 6 Enemies and protection against them...... 8 Capture ...... 8 Utilization...... 8 References...... 9
INTRODUCTION LIFE HISTORY
It is true but difficult to believe that the Description cephalopods (argonauts, cuttlefish, nauti luses, octopuses, and squids) are related The body of a c ephalopod (meaning feet to such quiet and peaceful mollusks as around the head) c onsists of the head, the clams, oysters, scallops, and snails. trunk, and the neck which connects the About 600 genera and more than to,OOO head and the trunk. The large head contains species of fossil cephalopods h~ve been two conspicuous and well-organized eyes described (Clench, 1959). Today, however, and usually a cartilaginous brain case. there are about 170 genera and more than Around the front of the head, cephalopods 400 species of these marine animals. have a group of elongated muscular arms
) with suckers on the undersides. (FeInales Locomotion and Inales have the SaIne nUInber of arInS, which regrow if cut off.) Inside the circle The cephalopods have several Ineans of of arInS is the Inouth, with two horny jaws, l ocoInotion. SOIne walk on the ocean floor called a beak, and a radula, a file like with their a r Ins . Others swiIn slowly by device . In addition, there are well-developed waving the fins while holding the body organs of hearing and sInell. horizontal, as do fish. All can Inove rapidly The trunk, the Inain part of the body, is by expelling water froIn the Inantle cavity surrounded by the Inuscular Inantle. The through the siphon. Bending the siphon Inantle encloses a large cavity with the two backward sends the aniInal forward; well-developed gills . The digestive tract, however, the siphon is norInally directed kidneys, and reproductive systeIn open into forward so t hat rapid spurts of Inove the Inantle cavity. The outlet of the Inantle Inent b,ackward are Inost character cavity is through the siphon, a short InUSCU istic. lar tube b eginning in the neck. Through it a re expelled the body wastes, the eggs, and t h e fluid froIn the ink sac. Water entering Reproduction th Inantle cavity through the siphon carries oxygen to the gills. All cephalopods except The sexes are separate, and the repro Nautilus, hav e an ink sac which cont ains a duction systeIn is cOInplex. One of the deep-brown fluid. a rInS of the Inale of Inost cephalopods is The Inajority of the cephalopod s have Inodified to transfer sperIn to the feInale. fins. With the Inodified arIn the Inal e takes the The skin contains Inany chroInatophores sperInatophores (a special capsul e , packet, (cells containing pigInent, which includes or Inass, enclosing sperInatozoa o r sperIn black, brown, and reddish yellow ). The cells) froIn his Inantle cavity and p l aces color of the body i s changed a t will by theIn in either the Inouth or the Inantle contracting and expanding the chr oInato cavity of the feInale . This action ends his phores. The color changes are believed to part in the breeding process . If h e places afford protection froIn eneInies , to help the sperInatophores in her Inouth, she catch prey, and perhaps to express certain Inoves theIn to her Inantle c avity. In the eInotions . Many pelagic and deep-sea Inale argonaut the Inodified arIn i s de - \... cephalopods possess lUIninescent organs. tached and left in the Inantle cavity of SOIne of the cephalopods have external the feInale with the sperInatophores shells while others do not. Nautilus, the Inost (MacGinitie and MacGinitie, 1949). In the priInitive living cephalopod, has a shell squids only the tip of the Inodified arIn into which it Inay withdraw it s entire body. is detached. The feInale argonaut has an e xte rnal shell, The sperInatophores r elease sperInatozoa secreted by a pair of ann s Inodified for which fertilize the eggs . The feInales of the purpose. In the course of evolution the different species lay eggs which vary other cephalopods lost the protective ex in size. The eggs pass through the siphon t e rnal shell, but gained speed and Inobility. into the water . They a r e usually fastened down singly or in clusters on bottoIn debris, Food and feedine; such as fragInents of coral or steInS of plants . So far as known, only the feInale All cephalopods feed on other aniInals octopus tends her eggs until they hatch, of the sea, preying on fishes and crusta and this Inay take as long as 4 Inonths ceans, such as crabs, prawns, and shriInps . (MacGinitie and MacGinitie, 1949); she Squids will even attack and eat injured does not feed during this tiIne . Squid eggs IneInbers of their own species. (fig. 1) do not require this care because These aniInals catch and hold prey with they are eInbedded in jelly. Besides pro the arIns. They sOInetiInes thrust the radula tecting the little eInbryos froIn fungus against the body of the victiIn and rasp growths, the jelly is distasteful or inedible the flesh. Usually, however , they bite into to Inost aniInals. Fertilized eggs of the the prey with the sharp beak and cut out cephalopods hatch into young which are wedge -shaped portions of flesh which they es sentially siInilar to the adult; developInent swallow whole. is gradual and direct.
2 l Figure 1.--Squid eggs (Loligo pealei). Courtesy of Robert K. Brigham.
FAMILIAR CEPHALOPODS are four rows of suckers down the entire length of the arms, except on the male's The most familiar living cephalopods fourth arm on the left, where they are are the cuttlefish, the octopuses, and the absent toward the base. The pair of tenta squids. cles h a s suckers only on the club-shaped e nds. The calcified cuttlebone (fig. 2), the Cuttlefish m ost characteristic feature of the cuttle fis h, lie s in the dorsal (back) portion of the About 100 speciel!J of cuttlefish (family mantle cavity. Sepiidae, group Decapoda) are known. They O r dinarily cuttlefish rest horizontally are found in mOl!Jt tropical and temper ate on o r near the sea floor, with their fins seas but only rarely in northern waters. gently waving, the tentacles withdrawn into They mainly inhabit shallow coastal pockets beneath the eyes, and the arms . waterl!J. depreue d . Thel!Je animals have a l!Jomewhat flattened The best known species of the cuttlefish body edged by a pair of rather narrow fins . i s Sepia offioinalis (fig. 3) of the Mediter Five pairl!J of arml!J encircle the mouth. One r anean. Ov al in I!Jhape and with a slightly pair (tentaclel) is longer than the rel!Jt. The flattened l!J urface, it attains a length of 6 to a rml!J are equipped with lucke rI!J which are 10 inche l!J. Its color ul!Jually ranges from stalked, with horny riml!J that may be pale g ray to dar k b r own or neutral tints. saw-toothed. On the shorter arms ther e Sometimes it has zebralike stripes.
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3 tic waters . They are found chiefly in shallow coastal waters, but some occur at great depths . The octopus (fig. 4) has a large head w ith a strong beak, and a small oval saclike body with an internal shell (a pair of vestigial structures to which muscles are attached) but no fins . The eight long, slender arms are of equal length and more or less united at the base by a thin mem brane. Two rows of cuplike suckers, one of its d istinguishing characters, extend the full length of each arm. The suckers are without stalks and without horny rims. The third arm on the left -hand side in the male i s modified for sexual purposes. Octopuses are solitary; that is, they do not live in groups . Ordinarily they live on the bottom of the sea among rocks . They hide in holes or in underwater caves, with their arms reaching out to seize victims . The position of the arms at this time reveals their hiding place. Sometimes an octopus digs its own den. It moves large stones to make the den and closes the entrance with stones when it moves inside . A pile of empty mollusk shells often marks the entrance of the den. There are numerous species of octopuses . Some species spread their arms from 12 to 14 feet . Ordinarily, however, the octopus does not attain one-half these dimensions, a nd many species have bodi es no larger than an orange . The common octopus alonJ the southern coast of Californi a i s Paroctopus bimaculatus . Farther north lives Octopus Figure 2. --Cuttlebone of the cuttlefish (Serw offi c
4 ( Figure 4.--This model of an octopus is shown at the entrance to a cavern in an exhibit in the American Museum of Natural History. New York City. Courtesy of the American Museum of Natural History. ) 5 produced a trickle of blood. A few minutes at the tips of the tentacles, but extend the later the victim complained of dryness in full length of the arms. The tentacles, like his mouth and of difficulty in swallowing. those of the cuttlefish, are retractile. He developed a loss of muscular control, In squids the internal shell is reduced to suffered from respiratory distress, and a long horny structure, called the "pen," was unable to speak. Placed in a respirator which extends the length of the trunk. at a hospital, he died about 2 hours after The most abundant of the American having been bitten. The man may have been squids belong to the genus Ommastrephe s particularly sensitive to octopus bites, and (called flying squids because they leap his reaction unusually severe. from the sea during storms and when pursued by enemies, sometimes landing Squids upon the decks of vessels) and the genus L oligo . Ommastrephes illecebro sa, varying from There are many species of squids (eight about 8 t o 14 inches in length, ranges from families, group Decapoda). They range southern New England to Newfoundland. from less than 1 inch to 75 feet or more Lol(qo peali occurs from New England to in length when the arms are extended. Florida, Gulf of Mexico, and Central Widely distributed, squids occur along America to Venezuela; it r eaches a length shores, on high seas , and from the surface of 12 to 18 inches . L.opalescens ranges down to great depths. Having broad environ along the Pacific coast from Puget Sound mental tolerances, these schooling, swift to Lower California. Mexico. and reaches animals seek areas where food abounds . a length of about 12 inches; it is popular in The squid has a l ong, tapered body the Chinese markets of the western United (steamlined for rapid swimming), with a States. These are the species most familiar triangular caudal fin on each side (fig. 5). to fishermen. Like the c uttlefish, it has 10 arms - - 8 mus The giant squids (genus Architeuthis), oc cular arms and 2 longer tentacles. Both curring at great depths in the Arctic and the arms and the t entacles a re equipped Antarctic wate r s, are the largest living with suckers which, like those of the inverte brates (fi g . 6). They are rarely cuttlefish, are stalked, with horny rims that seen by man and then generally only as may be saw-edged. The suckers appear only dead specimens washed up on beaches.
Figure 5.--Squid. Moroteuthis robusta (9 feet 8 inche s long). captured in a trawl net in November 1954 by the State of California research vessel N. B. Scofield. Court esy of the State of California Department of Fish and Game and lack W. Schott.
6 Figure 6.--A giant squid (Architeulhis) taken in the Hwnboldt Cur rem off the Pacific coast of South men a Amerian Museum of amral History expedition, headed by lichael Lerner (left). Courtes 0 \(, ho'/ Ler'ler.
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They reach a length of mo r e tha n 50 f eet c aught with s ines or dip nets. Squids are including the tentacles and a w eight of sometim es st r anded on shore in large 1, 000 pounds . Each sucke r i s almost 2 in c hes numb rs, spec ially late at night. and can wide. Large squi ds, living in the Humboldt b e p ick d up by hand . They can also be Current, rise at right in untol d thousands s nag g d w ith t r ipl hooks on the end of a and, when disturbed, squirt sepia-co l o red. lin if the hooks are baited with on or two ink-laden water fo r m any y a r d s (D uncan. s hiny b aitfi s h. An exp dltion of the AIneri 1941) . can Museum of atu r al H i story to the Humboldt Current off the Pacifl c c oast of ENEMIES AND PROTECTION Sout h AIn rica landed intact some giant AGAINST THEM s quid w l th rod and reel (Dunc an. 1941). Som e w ere nearly 9 feet l ong and welghed The c eph alopods use speed , ink clouds. m ore than 100 pounds (fi g . 7) . The i r tough c olor changes , and th eir beaks against beaks sla hing through w ire l eade rs of the foes such as dolphins. porpoises. sea birds. toughest st el obt ainable . these glant squlds seals, turtle s, and whales. The octopus showe red the f18hing boat w i th ink. m ust combat the savage conger and m oray Squlds. like octopu es . h ave b een known e e ls . a n d the giant squid has to meet the to blte when handled. ' f r m idable s wo r dfish and the sperm whale. Wh ile d e p e nding heavily on speed for es caping enem ies . those cephalopods hat have UTILlZATIO an ink s a c u s e it effectlvely. They sqUlrt out a cloud of b lack Ink which qUlckly Most of the cuttlefis h . oct o p uses. an d darkens the water. dis t racting the enemy. squlds a re useful. The p eople o f s ou h and perha ps temporarily paralYZing its Europe. outh A lao and the Pacliic 18lands sense of smell. Cha nging color at the same eat them--bolled. fned or un - dned. Con time to almost complete transparency. the SIderable quanti les 0 these nu ritlOus and cephalopod may esc pe to a safer slte. palatable mollusk are sold in he fresh - bsh As soon as they hatch, larval cephalopods markets of Umted- States Cl le s w l th large begin to fall prey to fishes. forelgn populations. such a Bosto n. ew York, Phlladelphla. and San F rancis co. In CAPTURE 1959, 23.554,000 pounds o f sqUlds. v a lued a $576,000, and 99.000 pounds o f octopuse , The cuttlefis h, the octopus, and the sqUld valued at $14,000. w ere landed in the are captured by man in various ways. Umted States . Before World War 11 the During the cuttlefish breeding season Japanese squid fishery took 75,000 t o fishermen in th e Gulf of aples sometimes 150,000 tons annually; in r e c e n t yea r s their tow a fem ale Sepia offiCinal' behind their catch has grown to a p eak of 600 ,000 to n s. boa ts and catch the males whl ch invariably Cuttlef ish and squids comprise a l a r ge pa r t follo w h er. Som e species of "epia that are of the diet o f cert ain m arine a n imal s, such partly n o cturnal in habits are attracted by as seals and w hales. In s o me par ts of t h e lights; fisherm en in various countries lure w orld c uttlefis h and s quids a r e c augh t o n a them into their nets by torche s or lanterns. large scale as b ait for c e r tain val uabl e food The c ommon octopu s . Oct op u l'ulgari . of fi s h es . Along the coast of ewfoundl and and the M e d iter r anean and neighbo ring Atlant ic in no r thern E u r ope squids a r e used widely coast s, i s often speared. A deep-water as bait fo r c ommercia l fi s hing . specie s , F.ldone mosc/lata . is trapped in from Squids are u sed fo r oth e r pur poses too . 60 t o 120 feet of water b ylowe ring ear t h e rn B io l o gy classes and marine l aboratories j ars and leaving them a few hours . T h e us e t h em in e x pe r iments . They are impor animals creep into these jar s t o hide. T he tant a l so in neurophysic a l research. Thei r c hoice method of k illin g a n o ctopus i s t o g i ant nerve f ibers greatly s implify experi stab i t deeply between the eyes . ments in neuromuscular transmission Squids are usually take n by commercial (Steinbach, 195 1; Walford, 1958) . Squids are fishe rmen in the United State s in larnpara often seen in public aquar iums . nets, gill nets, otter trawls, and pound nets . Cuttlefi sh are commercially valuable be In certain seasons and in some areas squi ds cause the cuttlebone (fi g . 2) is used in corne close to sho r e, especially at night. A preparing fine abrasives and dentifrices, light on a boat, a pier o r shore will attract and for supplying caged birds with lime and small baitfish, and squi d will often gathe r to salts . Fashionable Romans once used finely feed on them. The squids can often be ground cuttlebone as a cosmetic . The ink
8 Flgur e 7.--Giant squids (ArchltC'uthlSj taken In the Hwnboldt Current off the Pacific C I of SoUl America M useum of Na tural His ory expedi tion, headed by lIchael Lerner (piclurwa!xJve). T e rna lJ I and the largest one, welghing more than 100 pound Is nearly 9 feel lol'l17.. (ourt~" 01 \llCf.lll'/ I N"rr
ac also is a source of the natural brown Clench, Wilham. pigment called sepia which artists use. 1959. Cephalopoda. Enc c lop d 1 Because of their curi ous appearance, Amerlcana, vol. 6, p . 21 - 21 . c ephalopods are not widely used as human food. Pe rhaps market development pro Duncan, D vid D. grams, advertising, cooking demon tra 1941. Flgh mg glan of H mbo d tions, and attractively pac kaged products ational Geographlc a al-ln . vo could overcome the reluctance of mo t 9, no. 3, p 373-400. people to eat the e nutritious and pal atabl e mollusks. If that were done, cephal opod s H a l tead, Bruce could mat riall add to the world I food 19 9. Dange rou ma Tin supply. nell a rl lme P ar nd, 14 p. REFERECE
B n ill, . J. 1 1. Submarine roc ket . a tu a Hi - tor, 01. 0 , no . I , p . 8 -1 32.
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