MFR PAPER 1028

A cia e f lat lOnsh,p / found between lo ng-fin n d QLI/d dlstflbutlon and bottom w t r I mpuf tur

Aspects of the Distribution and Abundance of the Long-Finned Squid, Loligo pealei, Between Cape

Hatteras and Georges Bank

FREDRIC SERCHU and ARRE F RATHJE

ABSTRACT

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INTRODUCTION

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and I~ o ne l)f the AtlantiC Tllel11hcr~

of the genu~ Loli t:o hc 'rcclc~ ha~ recentl) rece lled much attentlL n in Northwest AtlantiC fi,hcnc\

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DATA AND TECHNIQUES

The NMFS's o rtheast Fisherie~

Center has conducted a semi-annua l trawl sur vey of the fi hing ground~

between the 27 m and 366 m isobath s from Nova Scotia to Cape Hatteras since th e fall of 1967 . Opera tions have been performed using the fish e ry research vessels Allwlro.I .1 II ' and DeI(/w(/re II . Each cruise covered a n app roxi mate surface area of 75.000 sq ua re mi les. A genera l descripti o n of th e gear a nd methodology empl oyed in th e traw l survey program is pro­vided by G rosslei n ( 1969).

In brief, standard 30-minute o tte r trawl haul s (3.5 knots towin g speed ) were accomplished at rand o ml y pre­se lected stat ions within each of 58 strata (Figu re I) . Sa mpl i ng was or­ganized according to a stra tifi ed ran­dom design which permitt ed a min im u m of two stations per stratum . T he to tal num ber of stat ions sam p led d iffered for each crui se (Ta bl e I), but the sam-

Table 1. - Inclusive dat es lor spring and l o ll Albalross IV survey cruises , 1967-1971 .

No of Year Season Dates stations

1967 Fall 17 Oct-9 Dec 271 1968 Spring 4 Mar-16 May 262 1968 Fall 10 Oct-26 Nov 275 1969 Spring 5 Mar-10 Apr 266 1969 Fall 8 Oct-23 Nov 276 1970 Spring 12 Mar-29 Apr 289 1970 Fa ll 3 Sei>-11 Sep 294

15 Oct-20 Nov ' 1971 Spring 9 Ma r-1 May 301 197 1 Fall 30 Sei>-19 Nov 303

I First leg of thi S survey operation was per­for med wi t h research vessel Delaware 1/ uSing same equipment and follow ing same procedures as Albatross IV .

piing scheme provided unbi ased ava il ­ability estimates fo r individua l stra ta and sets of stra ta . Ca tch da ta fo r L. pe(// ei from nine o f th ese c rui ses a nd the relati o n of ca tch to geogra phica l area, depth, a nd botto m water tem ­perature are presented in thi s paper. Compari sons between sprin g a nd fa ll catch patte rns are al so documented .

The survey data examined includes the results of 2,537 otter tra"" I stati o ns between Cape Hatteras a nd ova Scotia. The catch of long-finned quid amounted to a total of 7,483 kg. O f

Flgur. 2 . Ind .. 01 log m.an c al c h •• 01 L p".'.' per lo w by coe.tel zOn ••

Ill" 1I'I.tI. l)l) \ 1'':1,,'111 17 _'I k') \\.1

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rh..: Irdlrl1Ld IllL.!n l.dkh II I {,«lil I. ..:.lkul,llco dfler .. Il'.,< Irall fOrrll.illl'n anJ c pre .:d 111 krill 01

Idlogral1l r.:r ll'\\, \\." lIe'J.1 .111 InJe'\ llf abundance Il'!.! Ill,an l leh \alue ... hJ\e pre\ il'u 1\ heen ':Illplo\cd in a"'''e"rng L {', of, I il'Lk, ( ummer , 1969). anJ arc u,cful In e\.t1u"llng specie, ahunJJnce IrenJ, \\ hen the frequenc) olstnhulll'n of the L.itch I hi gh l) skc\\ cd ( ro ,kill 1971) \ uLh

a positl\el} ke\\ed d l,tnhutll'n I\ a, c lident In squid catches III the p re..,enl tud) a nd IS freq uent l) l,h ... en eo 1\ Ith

o th e r m a ri ne o rgan ISIll .

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l Spnng 1968 - 1971

20 1968

4 1969 1970

1. 5 1971

3

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0.5

Kg Lb Fa ll 1967-197 2.0

1967 4 1968

~3 969

1,5 1970 197

1.0 2

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II III IV V VI VII VIII IX COASTAL ZON ES, SW TO N E

12

Figure 3.-Comparison 01 average strat­ilied log mean catch 01 L. peale; per tow lor the coastal zones sampled during the survey cruises. with the stratilied mean bottom water temperatures record ­ed in each 01 the coastal zones .

Estimates of th e re la ti ve appare nt abundance l were derived for the Cape Ha tteras-Georges Bank area for th e sprin g a nd fall periods, a nd are pre­sent ed la te r in thi s paper in Figure 6. The calcul a ti o ns were accompli shed usi ng th e methods described by Ed­wards ( 1968) a nd involved the math e­matical extrapo lat io n of mean catch per tow data to obta in biomass va lues representative of th e areas sa mpled. Bri efly, th e technique e mpl oyed in ­volves us in g the trawl catch result as representative of the area swept by the trawl : th ese amounts are th en ex­panded by the area these trawl ca tches represent ( tra ta) a nd minimum e ti ­mates for th ese trata a re derived .

DISTRIBUTION

General

The lon g-fi nned squid is common to a bundant o n the cont inen ta l shelf off th e easte rn coast of the U ni ted Sta tes. Me rce r ( 1970b) prov ides evi­dence th at it reaches ova Scot ia but occurrence no rth of there is questi o nable. In th e south. this specie ra nges a t lea t to F lorida and the Gulf of Mexico a nd ha been repo rted from vario us ca tt ered a reas in theCaribbea n Sea (Yos , 197 1). Durin g the wa rm e r mo nth s (M ay-Octo ber) th e speci es is common in th e insho re zo ne off th e northeast e rn United States and we te rn

ova Scotia . Soviet exp lora to ry trawl­ing to depths of 800 m between Nova Scot ia a nd Cape H a tteras between 1958 and 1968 caught L. pel/lei most frequentl y between the -1-0 a nd 225 m depth zones. Th e frequency of trawl haul with L. pel/ lei in the catch was -1- 7.7 percent. The ran ge in size of th e squid taken durin g thi s stu dy was 5--1-5 em (mant le le ngth ) v.ith 11l0~t of the squid mea urin g 8-22 cm (Yov k. 19691.

I Following Ihe lermlnology suggested by Marr ( 1951) . 'relatlve apparent abundance may be denved Irom catch per unlt-of-eflorl data

Kg Lb SPRING 196 ~ -1971

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II III IV V VI VII VIII IX COASTAL ZONES, SW TO NE

Table 2.-Log mean catch in kilograms of L . peale; per tow. by stratum .

Coastal Zones SW to NE

Depth Zone II III IV V VI VI VI I Meters Fathoms

Spnng 1968-71

27-55 15-30 019 0 .29 56- 110 31-60 3.30 165 022 106 1 76 077 022 033

111 - 183 61-100 704 5.83 5.83 4.84 583 4 62 462 5 46 184-366 101-200 407 2.31 253 1 10 095 200 260 1 -2

Fall 1967-71

27-55 15-30 572 440 484 2.68 405 4 49 4 18 56-110 3 1-60 449 456 400 3.70 339 203 356 220

111-183 61-100 2 14 616 3.34 3.56 5 19 550 238 0-9 184-366 101-200 246 189 185 229 268 185 079 062

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119 107

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Geographic Distribution

The biannual surveys provide th e ab ilit y to compare th e distribution trends by coas ta l zo ne a nd ge nera l area. Stratified log mea ns of L. pel/lei catches obta in ed for each of th e nin e coastal zo nes samp led during th e spring a nd fall survey crui ses a re presented in F igu re 2. Fl uctua tion

Figure 4.-Comparison 01 average strat­ified log mean catch 01 L. peale; per tow for the four depth zones sampled during survey cruises , with the stratified mean bottom water temperature recorded in each of the depth zones .

Weight in Kg and Lb

1.0 2.0

1.5

in catches from th e same coastal zo ne are sometimes appare nt between cruises taken in the ame seaso n but general a bundance pa tt erns are a lso di sce rnibk.

In th e spring, L. pel/ lei is concen­trated in coasta l zo nes I (Cape Hat ­tera l. V (Hudson anyonl. and VIII (so uth ern Georges Ba nk) . atch rate dropped toward the ea tern e nd of Georges Ba nk during each of th e spring cruises a nd confirmed th e im ­i la r pattern obse rved by Su mmers ( 1969) a nd Mercer (1969a). Eas te rn

SPRING 1968 -1971 - 12

-----------9

0 .5 1.0 Mean Temp ~' ------------ -

~ 6

?: g a: w a..

1-0 .5

Log Mean Catc~_

-----------

/ /

/ /

/ /

/ /

/ /

/ /

I Meters ~ 27-55 56-110 111-183 184- 366

-

u ____ ll ____________ ~ __________ ~~~------~~~~--

~ Fathoms ~ 15-30 31-60 61-100 101-200 u Z DEPTHS <l: w ::E <.:> 9

Weight in Kg and Lb

8 1,0 [L

2.0 ~ tn

Mean Tem)

~ FALL 1967 -1971

1.5 t """" ------~ Log Mean Catch "' ......

1,0 ................................ 0,5

... ... ...... ... ---0.5

56-110 111-183 Meters ~ 27-55

Fathoms ~ 15-30 31-60 61-100

DEPTHS

---------

184-366

101-200

14

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Georges Bank rep resents th e approxi­mate boreal limit of the long-finned squid during the March-May period of th e surveys .

In th e fal l, L. pel/lei stocks exhibited a maximum a bundance in the south e rn a reas a nd genera ll y diminished in magni tud e toward the northeast. Catches u ua ll y were larger at Hudson Ca nyon (zone V) and ape Cod (zone VII) than tho e take n in adjoining a reas a nd probably a re indicative of local aggrega ti o ns of squid in th ese waters . Concentra ti o ns of L. pel/lei were invariably great e r during th e fall than they were in th e spring. Pre-umably this wa a result of an increa e

in population size res ulting from re­cruitment. a lth o ugh easona l dif­ferences in avai lab ilit y a nd traw l efficiency a re believed to account for part of the a ppare nt differences.

Bathymetric Distribution

Other investigation (Vov k. 1969 : a nd Summer, 1967) have es tabli shed th a t lo ng-finned squid concentrate a lo ng th e outer edge of the continental she lf during th e mo nths when inshore wa ter temperature are low ( Dece mber­Apri l).

Variation in catches of L. pel/lei with depth contrasted sharpl y between spri ng a nd fal l ; these differences a re indicated in T a bl e 2. Catch indices are presented by stra tum to illustrate sim il a riti e eX ls trng between regi o ns of equ a l depth in different coa tal zones .

Re la tively la rge conce ntrati o ns of squid occurred in spring in depth of 111-1 83 m (6 1-100 fm) . Abundance indices fo r thi s depth zo ne were severa l tim es greater than those for other depth s in each of the nine coastal zones. Indi viduals were eldom taken in less th a n 55 m a nd were never ob­tained in shal low waters north of C hesapeake Bay (coastal zone II ). Thcse observat io ns parallel the find­ings of previous investigators (Mercer, 1969a : Summer , 1969; Vovk , 1969), a nd are further substantiated by the large mid-depth (I I 1-183 m) catches of long-fi nn ed squid taken by the

Japanese fleet off o f New Yo rk d urin g winter and early spring. 1 97 1-1 972.~

Observa tion on bathymetric di s­tribution of L. pl'(t/ l' i in th e fall indi cated th a t th e species was dispersed throu ghout th e a rea in waters less th an 110 m . Concentra ti o ns inshore were ge nera ll y hi ghe r th a n during th e sp rin g. A imil ar phenomenon observed during th e autumn in th e a rea between Block Ca nyo n a nd south ern Georges Bank was noted by Vovk ( 1969).

A egrega ti on of individu a ls of simi lar ize wit h depth was common to both the spri ng a nd fa ll distribution of squid. Larger individuals usually were fo un d at greater depth than were smal ler specimens. This relation-hip is evident in the fewer squid per

kilogra m obtained in deeper waters during both seasons (Tab le 3). Comparable observations on the correlation of sq uid size with depth have been previously documented ( ummer . 1967; tercer . 1969a) .

Table 3.-Stratified mean number of L. peale; per kilogram obtained from the four depth zones sampled .*

Depth Zones

27-55 56-110111-183 184-366(m) CruIse 15-30 31-60 61-100 101- 200( lm)

Spring 1968 1036 304 172 136 Spring 1969 20.2 121 99 Spring 1970 66 .6 260 29 .5 13.4 Spring 1971 3346 29 .9 121 9.9

Fall 1967 43 .3 306 130 12.1 Fall 1968 304 200 154 15 .0 Fall 1969 36.3 18.7 15.4 17 .6 Fall 1970 27 1 29 .9 2024 32 .8 Fall 1971 521 51 .5 69 .7 46.4

• According to Summers (1969) 'The data may be converted to dorsal mantle lengths by a rough rule of thumb Five centimeter L. pea/el are approximately 44/kg , 10 cm L. pealel approx­Imately 22/kg, 15 cm approximately 11/kg , 20 cm approximately 5.5/k9 . and SO on ThiS rule applies to fresh animals of mixed sexes , but not to squid less about 5 cm dorsal mantle length nor mature ammals all of one sex

Distribution Related to Water Temperature

The presence and abundance of long-fi nned sq ui d was strongly influenced by wa ter temperature . T he

2 Personal communication with NMFS personnel and Boston Market News Report.

Weight in Kg ond Lb

SPRING 1968 - 19 1 2.0

::: 4 ~ 0:: 1.5 w el-

I 3 u tt u 1.0 z 2 <! w ::;: (.!)

0 .5 0 -.J

0 2 4 6 8 10 12 14 16 18 20 MEAN BOTTOM WATER TEMPERATURE (C)

Weight in Kg ond Lb

2.0

::: 4 0 t-o::

1.5 w el-

I 3 u tt

1.0 u z 2 <! W ::;: (.!) 0.5 0 -.J : . - . ..

.. ..

FALL 1967 - 1911

0 2 4 6 8 10 12 14 16 18 20

MEAN BOTTOM WATER TEMPERATURE (C)

re lationship of L. pl'l/ll'i with bottom water temperature is str ikin g. This relationship was prominent for catch and temperature changes between coastal areas (F igure 3). as well as for changes no ted with depth (Figure 4). Squid was generall y more abundant at hi gher bottom temperature both seasons. Sum mer (1969) reported that major catches of long-finned squid were restricted to a bottom temperature of SoC or higher during winter. Observations of catch in re­lation to bottom temperature in the present study sugge t that a simil ar situation exists during the spring and fa ll (Figure 5) . During both seasons the catch of L. pel/lei was greatl y dimini hed in strata with bottom temperatures below Soc. The largest

IS

Figure s.-Log mean catch of L, peale; per tow for strata sampled during the survey cruises , as a function of bottom water temperatures .

Figure 6.-Relative apparent abundance of L. peale; in the Northwest Atlantic (Georges Bank to Cape Hatteras) for spring and fall, 1967-1971 .

Spring OJ Foil Cf) 40 z 0 t-IJ... 30 0 Cf) 0 z 20 <[ Cf) :::J 0 I 10 t-

n n

~ ~ JI~I 1967 1968 1969 1970 1971

catches of squid were taken in wa ters 10-12 °C in the pring and at 1O-1-+°C in the fa ll .

INDEX OF ABUNDANCE

Seasonal Variations

Varia tions were observed in the relative apparent abundance between pring and fall seasons. In the pring

sea on th ere i a consistency from year to year for values of biomass to range well below 10,000 tons. They averaged 5.2 thousand tons for th e year 1968- 1971 (Figure 6) .

I n th e fall there was a sharp con­trast to the values derived for the spring month. The average aggrega te weight estima te for L. pe(l/ei stocks in th e area between Georges Ba nk and Cape H attera was 22.7 thou and tons dunng the yea rs 1967-1971. Durin g the period 1967-1969. there was a steady increase in th e fa ll in­dex of L. pe(l/ei but uccessive estima tes of re lative apparent abundance in 1970 and 197 I drop ped to one-quarter of the 1969 level. Unfortunately. data a re lacking o n reasons for this decline.

Unadjusted relative apparent abundance 0' Lo/igo (tons) .

Spring Fall

1967 16,790 1968 5.7 19 30,821 1969 4,878 40,998 1970 3,690 12,7 10 1971 6,599 12,058

Total 20,886 113,377

Average 5,221 22,675

For any given year, the fall index v. as everal Ilme greater than in the pring. Possible explanations of this

phenomenon may be related to the size ran ge of L. pea/ei during the two seasons and/or recruitment into the fi hery . Representati ve size (mant le length) frequency data are provided in Figure 7 , Reference to this figure demon trate that in the spring the population ampled con i ted of la rger animal than during the fall . Winter fi hlng mortalitJ may a lso contribute to the ob en'ed dec rea e in pop ul ation ize between the e ea ons. Additiona l

-' ;'! g ~ 'Z

~ ;;

8 ~ "' ~

3°1 20t

FAlL 67 1 n=1865

SPRING 69 n z 4348

30

lO!;-I.L,I _\~----=OI,.-.,JI~I n' ",mb" meo,",ed o 10 20 30

MANTLE LENGTH IN CENTIMETERS

Figure 7.-Length 'requency distributions 0' L. peale, taken on 'all and spring cruises , 1967-1971 .

research i req uired to delineate and evalua te the biotic and abioti c com­ponents infl uencing the abundance of thi s species.

It is interestin g to note that p re lim­inary evalu a ti on of fa ll urvey data for 1972 shows a strong upward trend from th e 1970 and 197 I index values (mean log weight/tow) .3 This infor­mati o n suggests that th e four years of modera te to heavy fi hin g on long­fi nned squid tocks has not . in it elf. been responsible for the decline from 1969 values show n in Figure 6.

The regularity with which fa ll abundance indice exceed spring val ues appears to indica te that surveys durin g the fall sea on are more va luabl e in determining changes in abundance. It hould al 0 be mentioned th a t at

least a po rti o n o f the long-fin ned squid stocks are di stributed a t dept hs shal­lower th an 27 m ( 15 fathoms ) which

3 Personal communication , M D Grossleln

16

mark th e inshore boundary of the survey a rea. There i no specific inform ati o n ava ilab le which allow es timates of the inshore component to be derived. One study, however, (Summer. 1968) indicates substantial number of lo ng-finned squid present in Vineyard Sound in early ovember 1967, a t depths of 20 m. Haefner (1964) records th e presence of L. pe(l/ei in Delaware a nd Chincoteague Bays during th e summer season , As the sha ll owest depth zo ne (27-55 m) am pl ed during th e fa ll ur veys ac­

count for about ha lf th e to tal. an equ a l o r grea te r de ns it y in water of les th a n 27 m could add up to 50 percent to the abundance index . Thi cou ld brin g th e to ta l ap pare nt abun­da nce to about 3-+ thou a nd to ns.

Values for both th e pring a nd fall squi d population must be con idered as minim um e timates . There is very little information o n th e vulnerabi lity of L. p ea /ei to th e trawl gear used in sam pling th e popul at io n . but pre um ­ab ly the effecti ve ness of the traw l i quite low. Low efficiency is not unusual when sampling pelagic and quasi­pelagic pecie (Edward. 1968).

Diel Variation in Catch

Analy i of catch ra tes by time of day indicates a relationship between day a nd night catches (F igure 8). Thi feature of behavior has previ ously been po inted out by Summers ( 1969). The phenomen on of dail y vertical mi gra ti on by marine animals is well established in th e literature. In the ca e of the long-fi nned squid it affect the catche by trawl gear which only samples a narrow band of 3-4 mover the bottom. I t follows that estimates of a bunda nce for species wh ich rise off the bottom dai ly must be cautiou Iy eva luated , We do not have positive inform ation o n the rea on for long­finned squid leaving the bottom but it may be associated with pur u it of food ( uch as euphausiid) whi ch are known to migrate in a simi lar fashion .

I n th e present study about 90 per­cent of the survey catch of long-finned

I U

~ U

--' <1

b ~

LL 0 ~ z w u 0:: W "-

30

20

10 f 1600 2000 2400

TIME OF DAY IN HOURS

Figure 8.-Diel variation of catches of L. peale; survey cruises , 1968-1971 .

squid was acco mpli shed durin g day­li ght hours . If ni ghttime catches a re inc reased by 90 pe rcent to a ll ow fo r squid whi ch we re un ava il ab le a t n ight and inc lude our a ll owance for the popul at io n com po ne nt th a t inh abited depths of less th a n '27 m . we wi ll a rri ve a t to ta l calcu la ted ap parent abundance of about 60 .000 to ns fo r the fa ll season.

SUMMARY

The d istribu t io n a nd relati ve ap­pare nt abu nda nce of L. pealei in th e Georges Ba nk-Cape H atteras a rea di ffe red markedly du ri ng spri ng a nd fa ll . In th e sprin g, th e sq u id were located in modest nu mbers o ffs ho re in depths of 111 - 183 m , whil e in fa ll indi vidu als were most a bundant in ­sho re a t dep ths less than I 10m . T h is striking change in po pula t ion can be accounted fo r by migrati on. Summers ( 1969) fo un d th a t L. peolei migrate

inshore in th e la te sprin g to spaw n and return to deeper wa te rs in th e late fa ll. H e a lso indi ca ted that th ese fall migra ti o ns were a res ult o f th e speci es' into le rance to bo tto m wate r tempera ture be low 8 °C. The results of th e prese nt stu dy co rro bo ra te Summe rs' findin gs a nd th e s imil ar o bse rva ti o ns repo rted by Vov k ( 1969) .

Rela tive appa rent abundance d if­fere nces be twee n L. peo lei stocks in spri ng and fa ll were as pro m i ne nt as th e di ffe rences in d istri buti on . T he average spring bio mass va lue was esti mated to be 5 .2 th ousand tons a nd was simil a r in magnitude to th e winte r abund ance of squi d fo un d by Summ ers ( 1969) in the mi d-A tl a nti c Bi ght d urin g 1967 a nd 1968 (3.4 a nd 2 . I th ousand to ns. respecti ve ly). T he mea n fa ll va lu e was over fo ur times as large (22 .7 th ousa nd tons) as th a t in the sprin g . A ll owin g for conse rvati ve expa ns io n of th e mean fa ll abu ndance index by vi rtue o f squ id located out­s ide the sur vey a rea (ins hore) a nd not cap tu red by the trawl d ue to di el m igrat ions , the ca lcu la ted ap­parent a bun dance co mes to 60,000 to ns . T hi s va lue does not ta ke into accou nt the avai labi lity of lo ng-finn ed squ id to the samplin g gea r. This in ­form at ion is no t known at th e prese nt time . Until coe ffic ients of ava il a bility and vulne rabi lity are asce rt a ined fo r L. peolei , a ll es t imates must be con­sidered tent ati ve.

Data made ava il abl e fr om th e 1972 fa ll grou ndfi sh survey sugges t th at the downwa rd stock flu ctu a ti o ns of 1970 a nd 197 I observed in thi s study are no t necessar il y fi she ry- re la ted. Th e increase o f co mme rcia l inte rest in sustai ni ng a fis he ry fo r L. peolei

necessi ta tes that m o re research be undertaken to bette r understand th e popul a ti o n dy na m ics o f thi s speci es .

LITERATURE CITED

Edwards, R. L. 1968 . Fishery resources of the North At la nti c area. U ni v. Wash . Publ. Fish ., New Ser. , Vol. 4, p. 52-60.

Grosslein , M . D. 1969 . Ground fi sh sur vey progra m of BCF Woo ds Ho le . Commer. Fish . Rev. 3 1(8-9) :22-35. 1971. Some o bservatio ns on accuracy of abu nda nce indices derived from research vesse l surveys. Int. Comm. N o rthwest A tl. Fi sh. Redboo k 197 1, Part \11: 249-266 .

Haefne r, P. A., lr. 1964 . Morphomet ry of the commo n Atla ntic squid, Loligo pealel, and the bri ef squid , Lo/ligll l1 cllla bre\'l.\ in Delawa re Bay. C hesa peake Sci. 5: 138-144.

Marr , J . C. 195 1. On th e use of th e terms abllllda llce, (/\ '",labJ/lIl' a nd "ppll re llf abllll­dan ce in fi shery bio logy . Copeia 195 1: 163-169.

Mercer, M. C . 1969a . A. T. Call1eroll cruise 130, o tt er-trawl survey from southern Nova Scoti a to Cape Hatteras, March-April 1967. Fish . Res. Boa rd Can ., T ech . Rep. 103, 24 p. 1969b. A. T. Call1 ero ll cruise 150, otter­t rawl survey of the Mid -Atl antic BIght, August-September 1968. Fish . Res. Board Ca n ., Tec h. Rep. 122, 47 p. 1970a. Ceph alopod resources a nd fisherIes in th e Nort hwest At lantic fo r th e Am. Malaco l. Union, 1970 Annu . Rep. , p. 30- '\3. 1970b . Sur la limit e se ptentrIo nale du calmar L oiIgo p ealel Lesueur. Nat. Can. 97 : 823-824. 1970c. A. 7. CO II/ el'llll cruise 157, otter­tra\\ I SUl'\ ey o f th e southwe'>le rn North Atla ntI C, Februa ry 1969. Fish . Res. Board C an ., T ec h. Re p. 199,66 p.

Sum mers, W. C. 1967. Winter dIstrI butio n of Lo ligo p ealel dete rm ined by explora tory trawling. BIOI. Bull . (Woods Ho le) 133:489. 1968 . Th e growth a nd size distribut io n of curre nt yea r cl ass Loligo p ealei. Bio I. Bull . (Wo ods Hole) 135:366-37 7. 1969. WInt er po pul atio n of LuiIgo pelliel in th e mld -Allanli c Bight. Bi oI. Bull. (Woods Hole) 137: 202-2 16. 197 1. Age and growth o f Luligo pealn. a po pulati o n study of th e co mmon Atl a nt IC coast squid. BioI. Bull. (Woods Hole) 14 1: 189-20 1.

Voss, G . L. 197 1. Th e cep halopod resources of the Caribbean Sea and adjace nt regIons. S) mpos iull1 on In\ eslI ga t lo ns a nd Resources of th e C arIbbea n Sea a nd Adj ace nl Re­gio ns, FAO (Foo d Agric. Orga n. U.N l. Fish. Rep. 7 1-2, p . 307-3 23.

Vov k, A. N . 1969. Prospec ts for a sqUId ( L uligo pe,d"l Lesueur) fi shery ( I n Ru".). Rybn . K hoz. 45( 10 ):7-9.

MFR Paper 1028. From Marine Fisheries Review, Vol. 36, No. 1, January 1974 . Copies o f this paper, in limi ted numbers, are avai lable from 083, Technica llnfo m ,ation Divis ion, Environmental Science Info rm ation Center, NOAA , Washington, DC 20235.

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