EDIBLE OF THE

by George H. Rees FISHERY LEAFLET 550

UNITED STATES DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE SERVICE BUREAU OF COMMERCIAL FISHERIES CONTENTS

Page

Introduc tion ...... 1 Natural Hi story ...... 2 Molting and gr0wth ...... 2 Reproduction and development .••..•••...••.••..•••.•.••.• 3 Autotomy and regeneration of lost legs .••••••••..••..•• 3 Commercially important crabs .•••••••.•••.••.••••••••••••.. 4 Atlantic and Gulf coast crabs ..••••. •...•.••••••••.••••.•.• 4 Blue ...... 5 Stone crab ...... 6 Rock crab and ..•...... 8 Green crab ...... 10 Deep Sea red crab ...... 11 Samoan crab ...... 1 1 Pacific coast and crabs •.•••.•••••••.•••.••••..•. . 12 ...... 12 ...... 14 Tanner crab ...... 15 Hawaiian crabs ...... 16 Kona crab ...... 16 Other specie s ...... 17 References ...... 17

UNITED STATES DEPARTMENT OF THE INTERIOR Stewart L. Udall, Secretary James K. Cttrr, Unde.r Secretary Frank P . Briggs, Assistant Secretary jor Fish and Wildlife FISH AND WILDLIFE SERVICE, Clarence F. Pautzke, Commissioner BUREAU OF CO MMERCIAL FISHERIES, Donald L. McKernan, Director

Washington, D.C. December 1963 EDIBLE CRABS OF THE UNITED STATES

by

G org H . R e Fi h ry Blo10 1 (Re arch) Bureau of Comm rCl 1 Fl h n U.S. Fl h nd Wlldllfe Servic B aufort, orth C rolln

INTRODUCTION v ry Impor n comm r e l kmg c r b of Al k , I 1 0 Cr b memb rs of th Crust cea hI ord r . (from L tln cru sta, hard sh 11), a cl s of th gre t mv rt br t phylum (from Gr k arthron. joint + pou . foo ), am­ All cr b po flve m 1 lth J01nt d legs nd a hard n d th p 1 r 1 lw y out r COy rlng, or xo ke1 ton. iost Wl h In cru tace n are quatlc nlm Is, and on b of th dlstlnguishlng char ct nstlcs of th m n Th cl s 1 that they br th by means of gllls. e Th memb r of the other cl ses of culhn Arthropoda, uch s th insect, spid r , Wlm r nd c nt1ped r e entl lly terre tri I mm 1 . Crustace ns r the rthropod th t oft n arm 1n th se s the In ct rm on I nd, nd th r 1 h rdly w y r of hfe m the se not followed by some A record m mber of th1 dlver died cl 5 . of h re r m ny order 1n the cl • Cr b b long to the order (from Gre k drka. t n pou . . foot), hlCh r f r to the f ct th t th of th1 ord r have of other f mih r dec the hnmp , pr wn , c r yf1 he , n and The order 1 further d1v1ded mto uborder , 15 mche nd 11 the b re placed in the (from Greek b achy , hort n me 1 quit ppro- for h bdomen, n p th t 1 folded ubord r

1 ( 7) The oys ter crab and i t s clo s e r e latives strengthen e d b y the deposition of calcium ( are member s of a g r oup c ommo n l y k nown salt s . as pea crabs, so called b~cause t heir bodies are about the size of peas. T he Whil e the hard s hell o f the crab forms majority of the larger specie s o f cla m s a fine s et of external a rmo r , i t a lso l i m i ts are subject to invasion by some t he si z e of t h e a n i m a l inside . For a crab of pea crabs. The ' s mantle cavit y, t o i ncre ase in size, i t must per i odically through which a current of water flows, shed i ts r i g i d oute r cove ring and form a is an ideal . Refuge is provided, new o n e . T h is proce ss i s called molti ng and food and oxygen are brought to the crab or ecdys i s. Pri or to molt, a new, soft by the ho st. Although most pea crabs living exoskel e ton i s formed i nside, a n d t he old in clams and mussels apparently do not shell beco m e s l o ose n e d. A s the c r a b b e gins harm their hosts, the oyster crab does to m o lt, the car apace , or back she ll, i s damage the gill tissues of the oyster; lifted, revealin g a g a p bet ween i t and t h e thus there is some justification for calling abdomen. The s hell splits on eit h er s i de it a parasite . of the under s u r face, and the p o ste r i or part of the crab begins to protrude . O ve r a period of a f ew minut e s, the crab com­ NATURAL HISTORY plete s t he p rocess, g r adually bac king out o f the old shell (fig. l ). Molting and Growth I mmediat e l y after molting, the s hell i s One of the dist inguishing characteristics soft and wrinkled; t his t hin a n d e lasti c of the phyl um A rthropoda is the pre sence new cuticle allows t he b ody to expand and of an all- enveloping exoskelet on, composed g r ow in size. Growth in size of the ani m a l basically of a mate r ial called chitin. In re sults from the copious i nta k e o f w ate r crabs, this chitinous exoskel eton is fu r ther a fter molting, with a cons equ e nt increa s ~

Figu re 1.--Molting. A blue crab is shown "backing out" of its old shell.

2 in the volume of the body fluid. As a re­ may be quite bulky and noticeable, is often sult, the new cuticle becomes stretched, referred to as the" sponge". The eggs are and the is considerably larger than carried until the y hatch, and during this before the molt. time the female i s called a " sponge crab" or a "berry crab" (fig. 2). In the soft shell state, the crab is prac­ tically helpless and is vulnerable to attack As in most Crustacea, the young of nearly by its enemies. Since many crabs are all crabs hatch as larvae that are quite cannibalistic, these enemies often turn out unlike thei r parents. The first larval form, to be members of its own kind. During the known as a z o ea (fig. 3), is a minute, trans­ molting process the crab seeks some parent organism that swims at, or near, secluded spot where it is safe from attack the surface cf the sea. It has a rounded until the new shell becomes rigid. The new body, often armed with long spines, and a covering soon hardens by chemical change, long, s e gme nted abdomen . The eyes are some of which is brought about by ex­ ve r y large in proportion to the body and posure to the water, and the crab is usually are not on stalks as they are in the adult. able to resume its normal activities within The legs a re not yet developed, and the a matter of hours after molting. swimming appendages are actually the future mouthparts of the crab. The number of times that a crab molts , during i ts lifetime, and the length of time After molting several t imes as it grows betwee n molts, var ies among species and i n size, the zoea passes int o a second I is affected by such factors as t e mperature larval form called the megalops (fig. 4). and the amount of food a vailable . In gene ral, In the megalops stage, the body and limbs as the crab i ncreas es in size through suc­ are more crablil:e, but the abdomen is cessive molts, the length of time between still large and not folded under. At this molts be..:omes progressively longer. In stage, the larva may either swim, or some specie s, an upper limit of size is c rawl about on the bottom on recently eventu ally reached and molting stops. O ther developed true legs. specie s continue to grow throughout life, even though molts occur less and less The m egalops molts directly to the "fir st frequently. crab" stage, a form closely resembling the adult. This is the last molt during which Reproduction and Development any major changes in appearance occur. Mating in crab s generally takes place There are a few crabs, especially those soo after the female has molted, often living in fresh water, which do not have while she is still in the soft- shelled any f ree-swimming larval forms. In these , state. At this t ime, the male transfers the young emerge from the egg as minia­ spermatozoa to the seminal receptacles ture adults. of the f e male where they remain until e gg laying begins. Some crabs, such as the Autotomy, and Regeneration of Lost Legs blue crab of the Atlantic and Gulf coasts, mate only once . The female receives e nough Crabs often lose one or more legs during spermatozoa at this one mating to fertilize a lifetime and, unless they have reached a all the eggs which she will l ay i n her l ife­ stage where they no longer molt, are able time, some of w hich may be produced a to r e place these with new limbs. Most year after mating. Other crabs, with a crabs have a highly developed ability to longer life span, mate each year a fter drop an injured leg. This process is re­ reaching sexual maturi ty. ferred to as autotomy. Autotomy is the severance of an appendage at a pre.formed When the eggs are mature, they enter breakage point as the result of a 'reflex the s eminal receptacles where they are action by the animal. When a leg is severed fertilized and then pas s outside the body at this breakage point, which is close to i nto a basketlike cavity formed by the curved the body of the crab, the resulting opening abdomen and the abdomina l appendage s is closed by a valve, and there is ver y (pleopods). The eggs become attached by a little loss of blood from the stump. It has sticky substance to long hairs on the also been shown that regeneration, or p l eopods, and a mass of eggs is formed growth of a new limb, takes place more under the abdomen. This egg mass, which rapidly at this point than anywhere else

3 Figure 2.--"Sponge crab". The female blue crab shown here may have 2 million eggs in the sponge. within the limb. The proce ss of autotomy reasonably large size; others are abun­ is an adaptation that pe r mits the animal to dance, good flavor, and a ready market. rid itself quickly of an injured limb at a Crabs which meet all of these requirements point where the possibilities for healing are found in the marine waters of the and regeneration are maximum. Autotomy Atlantic, Gulf, and Pacific coasts of the may also be of value as a means of escape United States, and the crab industry is when an appendage is grasped by anenemy. one of the important segments of American fisheries. A limb bud, within a protective sac , grows at the point of the break. The pro­ Atlantic Gulf Coast Crabs tective sac is thrown off at the next molt, and the crab then has a new and usable leg, The of the Atlantic and although it may be smaller than the lost Gulf coasts produced, in 1961, 155,458,000 one. Usually two or three molts are neces­ pounds of crabs, worth $8,427,000 to the sary to produce a claw or leg of normal fishermen. The blue crab, which supports size. the oldest and largest crab fishery of the United States, accounted for 98 percent of the total landings. Although this crab is COMMERCIALLY IMPORTANT CRABS fished intensively in the Chesapeake Bay, it is abundant in many parts of the South Many species of crabs are sought as Atlantic and Gulf coasts where it is scarcely food by man. Only certain species, how­ exploited. The rock crab and Jonah crab ever, possess the qualifications of an im­ of New England and the stone crab of the portant food resource. One of these qualifi­ South Atlantic and Gulf support small cations is that the crabs must attain a fisheries, but they could support much

4 larger ones. The green crab of New England is mainly of interest as a pest to the soft clam industry. The deep sea red crab, which live s in the deep water off the Atlantic coast, has a potential commercial value. A recent import, the Samoan crab, has been transplanted from the western Pacific to Florida, where it may thrive and become a commercially important species.

Blue crab. --The blue crab, (from Latin calli, beautiful + nectes, swimmer, and sapidus, savory), next to the and , is the most valuable of our waters (fig. 5). Its range is from Nova Scotia to Mexico, but it is not sufficiently abundant north of New Jersey to support a fishery. The Chesapeake Bay regionis especiallyfamous for its great numbers of blue crabs.

The blue crab is a member of the family Portunidae (from Latin Portunus, the Roman god of the port or harbor), the swimming crabs, and although it spends most of its time walking around on the bottom, it can swim with great speed when the occasion demands. Fully grown, it is between 5 and 7 inches across the back shell, although larger ones are sometimes caught. The Figure 4.--Megalops larva of the blue crab. (After Costlow and Bookhout.l back shell of the live crab is a dark green or brownish-green and is drawn out on z surfaces of the body and legs are white. crab is a very pugnacious a nimal and f_ The tops of the claws of both sexes show quickly attacks whe n corne r ed. It is this varying amounts of blue; in females, the type of behavior on t he p art of some crabs that is the basis for the E nglish word "crabby", which m eans cross or ill­ tempered.

The blue crab is e s sentially a shallow­ water crab, and i ts favori t e habitat is In the sounds, bay s, a n d cha nnels near the mouths of coastal r ivers. While normally an inhabitant of salt wate r , i t is also found in water that is brackish or even fresh. The life span of t his cra b is generally about 3 years.

The food habits of the blue c rab are quite diverse, for it eats a wide variety of plant and animal material , both living and dead . Because it is capable of quick movements, this crab is often able t o use its strong claws to catch small fish. T he blue crab i s definitely cannibali s tic and p r eys oninJured or soft- shelled m embers o f i t s own klnd.

Figure 3.--Zoea larva of the blue crab. (After Costlow and Blue crabs are c aught and marketed both Bookhout.) in a soft- and h a rd- shell condItion. The

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Figure S.--The blue crab. CallIM:cles sapulu.s. entire body of a soft-shell crab may be Blue crabs are also caught with trawls, eaten after cooking . Soft- shell crabs are dredges, and bai ted lines, such as the trot­ considered a great d el1cac y and bring a l i ne (fig. 7). The trotline is a long length of much higher price than hard- shell crabs. rope with pieces of bait attached at inter ­ The experienced fisherman can t ell when a vals. It is laid on the bottom, with i ts ends crab is about to molt, and in some areas anchored, and marked by buoys . To collect these crabs are placed in holding pens and, the crabs, the fisherman runs his boat after molting, are sold as soft crabs. The along the line, forcing the line to pass over hard crabs are sold either alive to the a roller attached to the boat. As the boat consumer or are steamed. In the latter moves forward, the crabs cling to the bait case, the meat is usually picked from the until they reach the surface, where the shell, packed in containers that must be fisherman catches them in a dip net and kept refrigerated, and sold as fresh crab places them in a basket or barrel. meat. Very little blue is frozen stone crab.-- The s ton e crab, Menippe or canned. The 1961 catch of blue crabs mercenaria (menippe , probably a fter Menippus, a amounted to . 152,758,OOO pounds, valued at Greek w r it e r and cynic, and Latin $8,149,000. mercenaria, hired for wages), i s a large, slug­ gish crab with a smooth, oval body and One of the most widely used and efficient massive, greatly enlarged claws (fig. 8). methods of capturing blue crabs is the crab It is a col orful crab, the young being a dark pot (fig. 6). This is a traplike device made purplish-blue, turning to brownish- red, of chicken wire mounted on a cubical, metal flecked with gray in the adult. The fingers frame about 2 feet in each dimension. The of the large claws are black, and the legs crab pot is designed to allow the crabs to are ornamented with red and yellow bands . enter easily through funnels, but to make Unlike the blue crab, it has no special pair their escape difficult. The pot typically is of swimming legs; rather, all its legs are baited with fresh fish. adapted for walking.

6 The stone crab is found along the coasts captured easily by hand, since it is sluggish of the South Atlantic and Gulf State s, but in its movements and is not particularly because of its habits, it is seldom seen by pugnacious. Caution should be exercised the casual visitor to the seashore. The in picking up a stone crab, however , as its stone crab lives aroundjetties, lying wedged claws are so powerful that a carelessly in the sand at the edge of the rocks. It is placed finger may be crushed. also found in shallow areas where it lives The flesh of the stone crab is considered in burrows, just below the low tide mark. a great delicacy and is said to r esemble These burrows extend obliquely downward lobster in flavor. The yield of meat from for a distance of 12 to 20 inches and are the body is slight, and only the claws of about 6 inches in diameter. Young stone stone crabs are marketed. The crabs are crabs are often found around oyster reefs, captured mainly with pots, and it is the or other bottoms with shells, where they usual practice of the fishermen to release live concealed under shell fragments. the crabs after breaking off their claws. Nothing definite is known concerning the Shellfish, such as oyster s and clams, survival of crabs whose claws have been are an important part of the stone crab's removed, but crabs are able to grow new diet. The powerful claws can easily crush claws. the shells, breaking off a piece at a time until the oyster or clam is exposed and Stone crab claws are either boiled and can be eaten. In spite of its formidable chilled prior to sale, or are sold fre sh­ . claws, the stone crab, if found, can be frozen. The 1961 catch amounted to 478,000

Figure 6.--Crab pot" TIlls cubicle trap has four openings. or funnels. inward. There are two COmPartments, and in the lower one is a bait-holding device. The upper one is a holding chamber. (After cargo.)

7 , . ~.

tI . '. ." :::'. .. : -' ~~. :'::;'-:':.: :';< ~./';' o .... ' .... " .

Figure 7.--Trotline. Sketch of a typical Maryland trotline being fished. Shows the anchored and buoyed line. with baits in place. passing over the roller on the side of the boat. The fisherman dip nets the crabs as they are brought to the surface. (After Cargo.) ( pounds, valued at $165,000. Although indi­ more heavily built than the rock crab and viduals in all the South Atlantic and Gulf has a much rougher surface. The color is States occasionally catch and eat stone brick red above and yellowish beneath. crabs, or offer them for sale, the present commercial fishery is confined almost en­ These crabs have scarcelybeenexploited tirely to Florida. commercially, but there is no reason why they should not be. Both are rather abundant, Rock crab and Jonah crab.--The rock range up to 6 inche s in width, contain as crab, irroratus (from Latin cancer, crab much meat as the blue crab, and are its and irroratus, speckled), and the Jonah crab, equal in flavor. They are commonly taken Cancer borealis (from Latin borealis, northern), along with in lobster traps , and range from Nova Scotia to the South At­ the few individuals who fish exclusively for lantic States but are most abundant on the these crabs often use modified lobster pots New England coast. Both crabs are found instead of crab pots. from the low tide level to depths of several hundred feet. The rock crab is more fre­ Since the crab meat is more di fficult to quently found in bays than the Jonah crab pick and is less profitable than lobster, which, when it is found close to shore, many dealers and fishermen feel that appears to pl'efer the more exposed loca­ handling crabs is not worth their time. tions on the outer coasts. Thus, the crabs, which otherwise might be a major source of income, are neglected These crabs are similar in appearance in favor of the lobster. Some dealers, how­ and may sometimes be mistaken for one ever, handle small amounts of crab meat in another. Both have the broadly oval carapace connection with lobster meat, mainly as a that is characteristic of the Cancer convenience to the buyer. and moderately large claws. The back and the tops of the leg s of the rock crab (fig. 9) The Cancer crabs of New England lend are an ivory color and covered with small themselves to small, family-type industry. purple bumps on granules. The color under­ Wives of lobstermen often pick and pack neath is white to ivory. The Jonah crab 1 S crab meat for local grocery stores. 8 Figure 8.- - The stone crab. Menippe mercenaria.

Figure 9.--The rock crab, Can cer irrora/us .

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Figure l O. --The green crab, . (P hoto courtesy of the S mithsonian In s titution.)

In some areas , p articularly in Maine , this a cro ss the back. T he colo r of the males practice is appar e ntly quite common. For i s gre en, m o ttled with black on the back this reas on, the stat istics on the catch of a n d yellowi s h u n de rne atL. The female is rock a n d Jonah c r abs are no doubt s o mewhat orange, m ottle d wit h black on t he back and less than the actual total. The combined deep orange unde rneath. Green crabs are catch for b o t h s pecies in 1961 was 2 ,096,000 membe r s o f the family of swimmi ng crabs, pounds , val ued at $102 ,000. but diffe r fro m the other members of this fa m i l y i n h aving the last pai r of legs flatte n ed, w i th poi nte d tips, rather than Gre en crab.--The green c r ab, Carcinus e x panded as ova l paddles. maenas (fr om Greek karkinos, a crab and .I1aenas, a myt hical G reek priestess), i s of interest i n t hi s c ountry , not b e cause o f i ts Green crabs burrow into the mud and qualities a s a n edible crustace an, but b e ­ sand flats to obtai n thei r food. They use cause of t he ext e nsive damag e which i t has the large front claws to hunt throug h the done i n r e c e nt years to t h e soft clam i n­ sed ime nts for animal life upon which they dustry o f N e w Engla n d . fee d . Their choic e food i tem is the soft clam, Mya arenaria, which has a rather thi n Green crabs are t e mperat e w ater cru s­ shell that the green crab is able to crush taceans which a p parently m o ved northw ard with its claws, thus exposing the meat. in re sponse to the tre nd towar d s m i lder Expe r i ments at the Bureau of Commercial wint e rs duri ng the past 50 year s . Prior to F i s heries Biological Laboratory at Booth­ 1900, the green crab was r e port ed to occur bay Harbor, Maine, . showed that one fro m Cape Cod southward to N ew J erse y. m e dium- siz e green crab eats about 15 B y 1930 , it had e x tended i ts range about small C! -inch diameter) clams each day. h a lf- way up the coast of Maine , and today Some experimental clam beds have had i t is n o t uncomm o n in Nova Scoti a. nearly all the clams eaten by green crabs in a matter of weeks. Two methods that The green crab (fig . 10) i s not a large have been developed for controlling green crab. The male s, w hich a r e larger than the crabs are (1) enclosing the clam flats with fe m a l es, r e ach a width of 3 to 4 inches a low wire fence and (2) surrounding the (

10 flats with lines to which poisoned baits are Most sp Clmen c pture ttached. Both methods are expensiv and trawhng were betw n n not completely effective. and weighed b tw en 1 and meat of th se c r b i The fishery for green crabs is a modest trawlers becom qui pp d operation carned on, especially in Massa ­ greater depths, thiS spec 1 s m ay om chusetts, with traps similar to lobste r pots. b ecome the source of a COmmerCl 1 fl h All of the catch is sold as bait for marine At present, the deep s a red c r b r m In sport fishing. The green crab is common an untouched resourc of unknown v III on the coast of Europe and i s used there and ext ent. as food . The total catch in the United States in 1961 was 126,000 pounds, valued at Samoan crab.--Th Samoan c rab, :ryl/ $11,000. errata (from Latm cylla, a leg ndary mon­ ster a nd erra, saw), although not n tiv to Deep sea red crab.--The deep sea r ed the United States, may someday be n Im­ crab, Geryon quinque dens (from Latin Geryon, portant commercial specl s h r e o Thl a mythical three-bodied monster and quinque, c rab (fig. 12), also known as th m ngrov five + dens, tooth), is worthy of mention crab, is the common edible c rab of lndl since it has the possibility of some day and is widely distributed m th supporting a commercial fishery. tropical Pacific . Like the blu c r b , th Samoan crab is a swimming cr b which This crab occurs off the east coast from thrives in estuaries, mouths o f river , nd Nova Scotia southward at least as far as shallow bays . Its chief advant g ov r th Cuba in depths ranging from about a hundred blue crab as a commercial sp Cl s l~ It to a few thousand feet. It appears to be larger siz.e . IndlVldu Is 8 Inches or mor,. most abundant beyond depths of 600 fe e t. wide are not uncommon, nd som sp CI­ mens are reported to r each wight of 5 The body of the red crab (fig. 11) is to 6 pounds. squarish and the walking legs are long and slender. The color is red or deep orange . The Samoan crab was succ ssfully In­ On each side of the front edge of t he cara­ t roduced into Hawaiian ,-"aters nr! p­ pace are five short spines or teeth to which parently IS well established ther , lthou~h the scientific name quinquedens refe r s . it now supports only a very sm 11 flshpry.

Figure 1l.--1be deep su red crab. Ge on onq.uden s (P t.o co..,,''' 0/ cAe .lAs . " .. ,...... J

I I After considerable deliberation, the Florida waters is the tanner crab; this crab has Board of Conservation decided to introduce scarcely been exploited b ut has the potential the Samoan crab into Florida waters. Ex­ for supporting a commercial fishery. perimental plantings were begun in Sep­ tember 1961 at several spots along the Dungeness crab.-- The Dungeness crab, southern tip of the peninsula and at one Cancer magister (from Latin cancer, crab and spot on the west coast. It remains to be maqister, chief), is found from the Alaskan seen if the Samoan crab will thrive in Peninsula to southern Cal i for n i a, but Florida and eventually support a commer­ reaches its greatest abundance in the area cial fishery. between and Southeastern Alaska . It is one of the largest edible crabs of the United States, reaching a width of 9 Pacific Coast and Alaska Crabs inches across the back. The crab gets its The crab fisheries of the Pacific coast name from the small fishing village of and Alaska are based almost entirely on Dungeness, Wash., where commercialfish­ two species, the Dungeness crab and the ing for this crab started. king c..rab. The fishery for Dungeness crabs began on the West Coast befor€' 1900, and, The Dungeness crab (fig. 13) is light among the crab fisheries of the United reddish- brown on the back with a pattern States, it ranks third, being exceeded in of lighter streaks and spots. In some speci ­ value only by the blue crab and king crab. mens, the anterior portion of the back is The fishery for king crabs was very small purplish. The underside varies from whitish prior to World War II, and mllhons of to light orange, and the inner and upper pounds of canned king crab meat were im­ sides of the anterior legs are colored ported from Japan annually. Since World crimson or purple. War II, the king crab resource has begun to be exploited and is now one of our most The fishery for Dungeness crabs takes rapidly expanding fisheries. Another crab place principally in offshore waters from which lives in Pacific coast and Alaska 12 to 120 feet deep, with only incidental (

Figure 12.--The Sarn>an crab, . (Photo courtesy of the S mithsonian Institution.)

12 Figure 13.--The ~ngeness crab, Cancer magister. (P hoto courtesy of the Smi thsonian Institution.)

catches from estuaries. Although commer­ entra nc e t unne ls. The bottom of the pot is cial fishing regulations vary i n different a bout 2 inc he s lar ger in diameter than the areas, there is one regulation i n effect top a nd has two i ron b ars reaching across wherever the Dungeness crab is fished-­ the botto m fra m e. Iron wei ghts are often only male crabs of a specific minimum atta c hed t o the bot tom frame to give the pot width of shell may be taken. The minimum adde d sta bility o n the ocean floor . The pots legal widths are set by the States, and are cove r ed w ith s tainless steel wire mesh presently vary from 5 3/ 4 inches to 6 1/ 2 and weigh about 9 0 pou n ds with out the iron inc hes, depending on the locality from whi ch weights. A line c onnects the pot on the the crabs are taken. The crabs reach legal ocean floor with co r k or plastic buoys on size in 3 to 4 years and probably live for the surfac e a nd is used fo r hauling the pot about 8 years. up to the fishing boat. T he surface buoys are bri ghtly c o l o r e d and n ot only mark the location of the pot but a lso serve to identify Dungeness crabs are caught by pots and the owner. ring nets, using fresh or frozen razor clams, squid, or fresh fish for bait. Con­ Rectangular pots are lightly constructed trary to common belief, fresh bait is much and weigh about 35 pou n ds. The dimensions more effective than old or spoiled bait. are about 30 inche s squ are and 12 to 14 Since the majority of Dungeness crabs are inches in height. The frame is covered caught in the open coastal areas, the pot with chicke n wire . B ecause of the light must be de signed and constructed so that weight and box like shape of this type of it will remain in an upright fishing position pot, its use is confined to the 'i n side, pro­ on the ocean floor regardless of heavy tected waters where it can be fished from wave action or tidal currents. The pots are small boats a n d lifted or hauled by hand. of two types, circular and rectangular. The large ground s w e lls and s trong tidal currents whi ch occur in the open expo sed The circular pot is the most common areas will cau s e thi s t ype of pot to tumble type, and is typically about 42 inches in on the ocean b o t t om. For this reason it diameter and 14 inches deep, with two is not suitable f or f i s hing in open areas.

11 The ring net is less complicated than the Anomura that the fifth legs are reduced ~ pot but requires greater skill in operation. in size. It consists of a pair of iron rings, the outer Lithode crabs are c h a racteristi c ally ring being 40 to 55 inches in diameter and found in the cold water s tow ard the poles the inner ring about half that size. A single and in the deep sea. The home of the king thickness of coarse netting covers and con­ crab is the cold waters of the North Pacific nects the rings. A bag of small mesh con­ Ocean, the Bering Sea, and the O kho t s k taining the bait is tied i n the center of the Sea. It occurs in the eastern Bering Se a , small ring. When the ring net is lowered to where bottom water temperatu re s are a t the bottom, it lies flat; but when it is 0 times below 0 Centigrade, and ice c o vers hoisted up, it forms a basket- shaped struc­ much of the fishing ground during the ture. Because the ring net must be hoisted winter. before the crabs can crawl off, fishing with this gear is limited to waters less than 60 Perhaps the most spectacular and com­ feet in depth. mercially important feature about king crabs is their large size. Male crabs with Dungeness crabs are marketed whole as an overall spread of 4 to 5 feet and weigh­ cooked, "dressed" crabs, or the cooked ing 15 pounds or more are not uncommon m e at is sold fresh, frozen, or canned. in Alaska waters. Female king crabs run Crabs are "dressed" by r emoving the much smaller in size than the males and digestive and reproductive systems and it is illegal to have them in possession. gills after cooking, and then freezing the The fishery, consequently, is based entirely crabs in plastic bags. Prior to 1957, nearly on males. the entire production offresh crabmeatwas market ed on the Pacific coast. Since that Adult king crabs migrate to relatively time, however, the market has been ex­ shallow waters (60 to 200 feet deep) in tended throughout the Uni ted States, and early spring for molting and spawniI}g. In frozen "dressed" Dungeness crabs are a general, crabs more than 4 inches in cara­ common sight in East Coast food stores. pace length are sexually mature and are probably 4 to 6 years old at this length. is the leading State in Dunge­ Females molt just before spawning. E ggs ness crab catches at present, followed by are attached to fine hairs on the abdominal , , and Alaska, in that appendages of the newly molted female and order. This crab also supports an important are fertilized externally. Males prob a bly fishery in British Columbia, Canada. The molt somewhat earlier than female s , but U.S. catch in 1961 amoJr.ted to 32,699,000 it is not entirely clear whether o r not pounds, valued at $4, 977,000. newly molted males participate i n spawn­ ing. Eggs are carried by the f e m ale fo r King crab.-- The king crab, Paralithodes about 11 months and hatch jus t before the camtschatica (from Greek para, beside--thi s next spawning and molting season. is a prefix used in scientific names to mean "closely resembling" + Lithodes, a King crabs in their first 2 o r 3 years of closely related genus, whose name comes life are shallow water dwellers and may be from the word lithos , stone, and camtschatica, found in large schools, or " pods " , close from the Kamchatka Peninsula which ex­ to shore. As they grow older, t h ey enter tends into the Bering Sea), is not closely into the annual adult migration. In general, related to the other commercially important this is a movement inshore to speci fic crabs of the United States. In fact, it is not spawning areas during winter and early even a true crab. The king crab (fig. 14) is spring and a reverse migra t ion offshore an anomuran, and a member of the family to feeding areas in summer a nd fall. These of lithode, or stone crabs. The name refers offshore feeding areas m a y be i n waters to their heavy, rough shell which resembles up to 1,000 feet in depth. a stone. King crabs in Alaska w aters are caught The lithode crabs at first glance appear almost entirely by pots a n d ring nets. The to have only four pairs of walking legs; pots, baited with fish o r clams, have however, they all have a small fifth pair tunnellike opening s leading i nsi d e . Some of legs that are bent upward and often in­ king crab pots are circular, but the most serted under the carapace. It i s one o f the common type is built on a m e tal frame, distinctive features of the suborde r 7 feet by 7 feet by 2t feet . 14 :tit" ~.-. .{.." .. _- ' , I

Figure 14.--The king crab. Paralithodes camtschatica. (P hoto courtesy of the Fisheries Research Board of Canada.)

During the early years of the U.S. king Prior to World War II, the U.S. fishery crab fishery, trawls and tangle nets were for king crabs was very small, and about the principal gear employed. The tangle 10 million pounds of canned crab meat net consists of a waU of net supported at were importe d from Japan each year. This its upper edge by floats and weighted at imported pack consisted almost entirely of the bottom by leads. The net is set so that king crab, a large p a rt of which was taken it stands upright from the bottom. The in waters adjacen t to Alaska and packed in crabs walked into the net and became en­ floating canneries. Since World War II, this tangled in the meshes. Gear restrictions valuable American resource has begun to be outlawed tangle nets in 1955 and have suc­ exploited by the United States, and the cessively restricted trawls from the inside Alaska king crab fishery is now one of our waters. Only a few thousand pounds of king most rapidly expanding fisheries. The U.S. crab per year are now caught by trawls, catch of king crab increased from 1.5 mil­ and pot fishing is encouraged in all areas. lion pounds in 1950 to 2 8 million pounds in 1960 and to 43 million pounds in 1961. The King crab meat is processed for the value of the 1961 catch was about $3.9 market by freezing and canning. Because million. the meat must be processed quickly to avoid deterioration, floating cannerie s are Tanner crab.--The tanner crab, used on the coast of Alaska. These self­ Chionoecte s tanneri (from Greek chion, snow' + contained units move from one part of the nektos, swimming, and tanneri for Lt. Com­ coast to another and are supplied with mander Z. L. Tanner, Commander of the crabs by a number of fishing boats. King U.S. research vessel Albatross, whose ex­ crabs are canned, stored, and transported plorations produced the first specimens of back to home port aboard the cannery ves­ this species), lives in the deeper waters sel. The king crab is our most important of the Pacific coast of NorthAmerica, from source of canned crab meat. the Bering Sea to southern California.

15 Figure 15.--The tanner crab. Chionoectes tanneri. (Photo courtesy of tile S mithsonian Institut ion.)

This crab belongs to the family of spider the potential exi s t s for a much l a rger crab crabs, so-called because their legs are fishery than the p r esent one. long and s lender in proportion to their bodies. Kona crab.-- The Kona crab, ranina (from Latin rana, ) i s the most important The tanner crab (fig. 15) grows to a commercial spe c i es of Hawaii an crabs. relatively large size. Specimens 5 to 6 The Kona crab (fi g . 16) is a member of the inches across the back a nd 2t feet between family , the so-called frog cra,bs. the outstretched legs are not uncommon. These c r abs have an elongated body, and The claws are small in relation to the other the last pai r of legs is held in a horizontal legs. It is a deep-water crab and is seldo m position , sugge sting the hind legs of a found at depths of less than 50 0 feet. T he fro g. tanner crab has a pleasant flavor and, if a market could be developed, mig ht become The K o na crab is (3.ught by vessels em­ the basis for a commercial fishe ry. Sma ll plo ying lift nets bai t e d with fish or fish numbers of tanner crabs are taken a l on g par t s . T he se nets measure about 3 feet in with king crabs, but, at present, this species diamete r, i f round, and about 3 feet by 3 represents an untapped natural resource. f eet, if square. About 30 to 50 of these are The total U.S. catch in 1961 was only 7,000 hung f rom a mai nline and hauled in by pounds, valued at $1,000. winc h . At t i mes, the nets are set individu­ a lly by operators of small boats and pulled Hawaiian Crabs b y hand. This species is usually taken at depths of 90 to 120 feet, on flat, sandy The present c o mme rcial c atch of crabs bottoms. The average carapace length of in Hawaii is small, t otaling 29, 500 pounds Kona crabs in the commercial landings is in 1961, worth $18,200. Much remains to be about 5 inches. Average weight is about 1 learn ed about the b i olo g y, abundance , and pound. Large individuals with carapace distribution of t h e H a waiia n c r abs of com­ l engths up to 7 inc he s and widths up to 6 mercial value, but t h ere i s n o doubt t hat inches have been recorded. The flesh is

16 ,)

Figure 16.--The Kona crab. , (Photo courtesy of the Smithsonian In sti­ tution,)

highly esteemed for food and is commonly Dow, Robert L. , and Dana E . Wallace. served in restaurants as a specialty. 1952. O bservations on g r e e n crabs (C, maenas) in M aine. Maine Depart­ Other species.--Other Hawaiian species ment of Sea and Shore Fisheries, of lesser commercial importance are the F isheries Circular No . 8, p. 11-15. wh' te crab, Portunus sanguinelentus; the red crab, Podophthalmus vigil; the Samoan crab, Dumont, Wm. H., and G. T. Sundstrom. Scylla serrata; and the aama crab, 1961. Commercial fishing gear of the grapsus tenuicrustatus, These constitute a small United State s. U .S. Fish and Wildlife part of the commercial landings and are Service, Circula r 109, 61 p . usually caught by lift nets or scoop nets. The aama crab is caught by a string loop Hipkins, Fred W. attached to one end of a bamboo pole. Thi s 1957. The Dungeness crab industry. species inhabits the spray zone of rocky U.S. F ish and Wildlife Service, Fish­ shores where the use of lift nets and scoop ery L eaflet 439, 12 p. nets is practically impossible. MacGinitie, G. E., and Nettie MacGinitie. 1949. Natural historyofmarineanima1s. REFERENCES McGraw-Hill Book Co., Inc., New York, 473 p . Buchsbaum, Ralph. 1948. without backbones. Min e~ , Roy Waldo. The University of Chicago Press, 1950. Field book of seashore life . G. P. Putnam's Sons, New York, Chicago, 405 p. 888 p. Cargo, David G. Olden, June H. 1954. Maryland commercial fishing 1960. Crab from sea to consumer. U .S. gears. III. The crab gears. Mary­ Fish and Wildlife Service, Bureau ) land Board of Natural Resources , of Commercial Fisheries, Technical Educational Series No. 36, 18 p. Leaflet 29, 35 p .

17 Phillips , J . B. tion, early development, growth, and 1939. The mar ket crab of Californi a migration. U.S. Fish and Wildlife and its close relatives. California Service, Commercial Fisheries Re­ Fish and G ame, vol. 2 5, n o . 1, p. view, vol. 20, no. 6, p. 6-17. [Also 18- 29 . as Separate No. 512.]

Pounds, Sandra Gail. Van Enge l, W. A. 1961 . The crabs of Texas. Texas Game 1962. The blue crab and its fishery in and Fish Commission, Bullet i n No. Chesapeake Bay. Part 2-Types of 43, 57 p. gear for hard crab fishing. U.S. F i sh and Wi ldlife Service, Commercial Scattergood, L e s lie W. Fisheries Review, vol. 24, no. 9, 1952. The distribution of the green c rab, p. 1-10. [Also as Sepal'ate No. 655.] Carcinides maenas (L. ), in t he north­ western Atlantic. Maine De p artm e nt Waldron, Kenneth D. of Sea and Shore Fi s heries, Fi s he r ie s 19 58 . The fishery and biology of the Circular No.8, p. 2 - 10. Dungeness crab Cancer magister Dana) in Oregon waters. Fish Commi ssion United State s F ish and Wildlife Service . of Ore gon, Contribution N o. 24, 43 p. 1962. The Alaskan king crab. U.S. Fi sh and Wil dlife Servic e, Fishery M arket News, vol. 4, no. 5A, 107 p . Webe r , Douglas D., and Takashi Miyahara. 1962 . Growth o f the adult male king crab, Van E ngel, W . A . Paralithode s camtschatica (T i I e s i \l s). 195 8 . The blue crab and its fishery i n U.S. Fish a n d Wildlife Service, Fish­ Chesapeake Bay. Part 1- Reproduc- ery Bulle t in 2 00, vol. 62, p. 53-75.

MS # 1287 GPO 861.186

Created in 1849, the Deportment of the Interior-Americn's Depnrtn.ent of Nntural Resources-is con cerned with the,mnn­ ngemenl, ron5(>rvntion, nnd development of the Nntion 's wnt er, fish, wildlife, minernl, forest, nnd pnrk nnd recrentional re­ sources, It n Iso hns llllljor responsibilities for Indian nnd Territorinl affnirs, As the Nation's principal conservation agency, the Depart­ ment works to assure that nonrenewnble resources are de"eloped nnd used wisely, thllt pnrk and rec reationnl resources are con­ served for the future, nnd that renewnble resources make thei r full contribution to the progress, prosperity, and secur ity of the l'nited States-now and in the fu ture,

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