UNIVERSITY OF WASHmGTON DEPARTMENT OF OCE"ANOGRAPHY Seattle, Washington Technical Reports. Nos. 174, 175, 176, 177, 178, and 179

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1 SEATTLE,

2 UNIVERSITY OF WASHmGTON DEPARTMENT OF OCE"ANOGRAPHY Seattle, Washingtn Technical Reprts Ns. 174, 175, 176, 177, 178, and 179 A COMPlLATION OF ARTICLES REPORTING RESEARCH SPONSORED BY THE OFFICE OF NAVAL RESEARCH... " Office f Naval Research Cntracts Nnr-477(10) and Nnr-477(37) Prject NR Reference M66-78 December 1966 R' Chairman. Reprductin in whle r in part is permitted fr any purpse f the United states Gvernment

3 ., ARTICLES REPORTmG RESEARCH SPONSORED BY THE OFFICE OF NAVP:L RESEARCH Technical Reprt N. 174 D>ENTIFICATION AND DETERMINATION OF ORGANIC ACIDS IN SEA WATER BY PARTITION CHROMATOGRAPHY, by Tadashir Kyama and Thmas G. Thmpsn. The Jurnal f the Oceangraphical Sciety f Japan, 20(5): Technical Reprt N. 175 QUANTrrIES OF ZOOPLANKTON AlID PROPAGATION OF CALAmJS FINMARCHICUS AT PERMANENT STATIONS ON THE NORWEGIAN COAST A1'ID AT SPITSBERGEN, ,' by Ulf Lie. Fiskeridirektratets Skrifter, Havunders kelser, 13(8): Technical Reprt N. 176 MAGNETIC AND PETROLOGIC STUDIES OF SEDJMENT FOUND ABOVE BASALT IN EXPERIMENTAL MOHOLE CORE EM?, by M. D. Fuller, C. G. A. Harrisn, and Y. R. Nayudu. Bulletin, American Assciatin f Petrleum Gelgists, 50(3): ". Technical Reprt N. 177 AN INSTRUMENT SYSTEM TO MEASURE BOUNDARY-LAYER CO:NDITIONS AT THE SEA FLOOR, by Richard W. Sternberg and Je S. Creager. Marine Gelgy, 3(6): Technical Reprt N. 178 SOME CONSEQUENCES OF THE DECOMPOSITION OF ORGANIC MATTER IN LAKE NITINAT, AN ANOXIC FJORD, by Francis A. Richards,.. Jel D. Cline, William W. Brenkw, and Larry P. Atkinsn. Limnlgy and Oceangraphy, 10(Suppl.): R185-R Technical Reprt N. 179 LOW-FREQUENCY SEA LEVEL OSCILLATIONS ALONG THE PACIFIC COAST OF NORTH AMERICA, by Gunnar I. Rden. Jurnal f Gephysical Research, 71(20):

4 ., UNIVERS:TY Of WASHINGTON DEPARTMNT Of OCNOGRAPHY TECHNICAL REPORT NO Reprint frm Fiskeridirektratets Skrifter, serie Havundersekelser, Vl. 13, N.8 QUANTITIES OF ZOOPLANKTON AND PROPAGATION OF CALANUS FINMARCHICUS AT PERMANENT STATIONS ON THE NORWEGIAN COAST AND AT SPITSBERGEN, By Fiskeridirektratets Havfrskningsinstitutt INTRODUCTION Zplanktn has been cllected at permanent ceangraphic statins alng the Nrwegian cast since The purpse f these lng-range planktn studies is mainly t fllw the annual and seasnal changes in the fd cnditins fr planktn-feeding fishes. Als, the samples prvide material fr an analysis f the abundance f eggs and larvae f cmmercially imprtant fishes in Nrwegian castal waters. The permanent statins were riginally Sgnesj0en, Ona, Skrva and Eggum (Fig. 1). Skarsvag and Kngsfjrden at Spitsbergen were added in 1955 and 1957; the sampling at Qna was abandned in Since 1948, zplanktn has als been cllected at the weather ship "M" at 66 N, 02 E in the Nrwegian Sea. The hydrgraphical cnditins at the varius statins are representative f the cnditins in the Nrwegian castal water at the crrespnding latitudes. Hydrgraphic data frm the permanent statins have been cllected simultaneusly with the zplanktn and prcessed at the hydrgraphy sectin f the Institute f Marine Research, Directrate f Fisheries. The zplanktn was cmpletely identified and cunted frm (WIBORG 1954), but has since been less thrughly analyzed. The emphasis has been n measuring displacement vlumes, the dminating species f zplanktn have been nted, and fish-eggs and larvae have been identified and cunted. Since 1959 the percent cmpsitin f develpment-stages f Calanus finmarchicus has als been estimated. WIBORG (1954) described the annual and seasnal changes in the quantities f zplanktn at the permanent statins frm 1948 t Present address: Department f Oceangraphy, University f Washingtn, Seattle Washingtn

5 Fig. 1. Permanent zplanktn statins (frm WIBORG 1958). He als discussed the cmpsitin f the zplanktn and varius aspects f the bilgy f the imprtant species. The quantity f zplanktn at the permanent ceangraphic statins until 1958 was reprted by WIBORG (1958 and 1960). The current paper reprts n the zplanktn quantities and the prpagatin f Calanus finmarchicus at Sgnesj0en, Skrva, Eggum, SkarsvAg and Kngsfjrden during the perid

6 , 7 MATERIAL AND METHODS, The present reprt is based n 734 samples frm five statins. The material frm Skrva is by far the mst cmplete, averaging mre than eight samples per mnth, while the average fr the ther fur statins is less than fur. The majrity f samples were cllected with Nansen-nets with muth diameter 70 cm and mesh size 0.2 mm. In 1961 and 1962 this gear was replaced by Juday-nets with 40 cm diameter in the upper ring, and the same mesh size as the Nansen-nets. When calculating the vlume f zplanktn per square meter f surface, it has been assumed that the catch per unit area was the same fr the Nansen-nets and fr thejudaynets. Tw samples were taken per statin per sampling date: ne sample frm the 50-0 m layer, the secnd frm the bttm t the surface. All the samples were preserved in 5-10 percent frmalin. The vlume f the zplanktn was measured by the displacement methd (WIBORG 1954). Presence f large quantities f phytplanktn may reduce the accuracy f the measurements cnsiderably by clgging the sieves, but by washing the samples thrughly befre measuring vlume, mst f the phytplanktn can be remved. The vlumes f zplanktn per square meter f surface have been calculated and the mnthly means f these values are presented in Figs The prpagatin f Calanus finmarchicus has been studied by determining percentage distributin f the first 100 Calanus cpepdites cunted when examining the sample under a dissecting micrscpe. This methd prbably des nt meet the requirements fr randm sampling; therefre, the data have nt been used fr any statistical evaluatins. The bias intrduced by the methd f subsampling des nt permit much emphasis n single bservatins f stage distributin, but demands cnsideratin f trends in large numbers f samples. The percentage develpmental stage distributin as mnthly means averaged fr the years at the varius statins is presented in Figures 7-1O. VOLUMES OF ZOOPLANKTON AT THE PERMANENT STATIONS, Sgnesjeen (Fig. 2) Very few samples are available frm this statin, a circumstance which makes the study f seasnal changes in the bimass uncertain. The spring increase seemed t start in April, the maximum was reached

7 8 30r y SOGNESJ EN 25 N "'::i20 Ul l1j 15 ::::>...J...J 10 ;:! t- [ [ J F M A M J J MONTH Fig.2. Mnthlymean ttal vlumes in ml/m 2 f zplanktn at Sgnesjeen, in April r May. A secnd, less prnunced peak culd be detected in July-August. WIBORG (1954, 1958, 1960) fund the same general trend in the seasnal variatins in bimass f zplanktn, and his data reveal cnsiderable variatins frm ne year t anther. Hwever, WIBORG als had relatively few bservatins frm this statin, which may accunt in part fr the variatins. Skrva. (Fig. 3) The quantities f zplanktn in the 50-0 m samples were very pr during the first three mnths f all the years investigated. The spring increase was bserved frm the middle f April, and fr all years tw significant peaks were fund; ne in May and ne in June. A third, less prnunced peak ccurred in September-Octber. Fairly high densities f zplanktn were bserved all year rund in the m samples. The minimum was fund in March, and the Same three peaks ccurred as in the 50-0 m samples. The tw separate peaks in May and June are nt revealed by the mnthly mean values per m 2 Frm February n, an increasing prprtin f the zplanktn was.fund in the upper 50 m layer, and during April, May, and June, mre than 50 / 0 f the ttal standing stck ccurred in this layer. The relative A s N

8 ": 70 9 SKROVA 60 N50..J II) llj 630 >..J ,,--, /'... /' \' 1\ I \... '\ I \... \ / \,..." I \ \ \ ' \ I \,' \ I \", \ I \ '., \ I I }.\. Y. ", \, I :' j \""", ' I.:, \,... " " :' /...\ " 1 : I '.' " 1.: / ".\ -_... I :' e.,......,' I:'/' '/,., /-.--,>',, :" \...,,.' --.. "....- :..../.. '. I I...;.1,-.., i I '.. J F M A M J J MONTH Fig. 3. Mnthly mean ttal vlumes in ml/m 9 f zplanktn at Skrva, density f zplanktn in the 50-0 m samples was als prminent during the peaks in September-Octber 1959 and 1961, but nt in Frm Octber the amunt f zplanktn in the upper 50 m layer decreased rapidly, and during December and January less than 5 / 0 f the ttal bimass was fund in this layer. The variatins in zplanktn vlumes per square meter f surface frm 1959 t 1962 (Fig. 3) crrespnd largely t thse bserved by WIBORG (1954, 1958, 1960). He demnstrated that cnsiderable changes may ccur at this statin frm ne year t anther as regards time fr the peaks and the mean annual richness f zplanktn. A s N Eggum. (Fig. 3) The spring increase in the 50-0 m samples at this statin was always fund in April, reaching a maximum f vlume in May. In 1960, n ther peaks were fund, whereas a secnd peak ccurred in August 1961 andjune The m samples frm 1960 revealed peaks in May and early July, and a slight increase in Octber. (Fig. 4). The same pattern was fund in 1961, but as n samples were cllected later than September,

9 N J z r :-. "'/' f. \ " / '., : I '\. ' "\...\ : I " j/ \ '.' : I,,,,' \.\ : I,,,, / \ '., : I," \ : I I \ " :,' r-_ J' \ ".\ : I I \ - :, f/ / \... \. " ' \, ; / \ " 1,....,..:*:':".: / "- :.:,-' :..::.;;:;';"...1'..._ EGGUM..., I I I I I I J F M A M J J AS 0 N 0 MONTH Fig. 4. Mnthly mean ttal vlumes in mljm 2 f zplanktn at Eggum, an eventual third peak culd nt be detected. Als in 1962 the spring maximum in the m samples was fund in May, and a secnd peak seemed t ccur at the end f June. The zplanktn density in the winter seasn frm September t April was extrmely pr and n significant difference between the 50-0 and the m samples was fund. During the summer seasn, hwever, the vlumes f the m layer were cnsiderably higher than the vlumes f the m samples. WIBORG (1954, 1958) fund largely the same pattern, and he emphasized the extensive variatins frm ne year t anther. Skarsvag. (Fig. 4) The spring increase in the 50-0 m samples was bserved frm April May. The maximum was as a rule fund injuly, but in 1962 it ccurred as early as the middle f June. A small secnd peak culd be detected in August-September 1960 and The vlumes f the m samples fllwed the same pattern. The main part f the zplanktn seemed t be cncentrated in the upper 50 m during the first half f the year, while the relative density f zplanktn in this layer decreases after the spring maximum when the planktn descends fr verwintering in the deeper water layers.

10 , SKARSVAG N 80...J ::a ẕ 60 ti'i W ::a ::>...J 040 >...J... «ọ J F M A M J J MONTH A 5 Fig. 5. Mnthly mean ttal vlumes in ml/m 2 f zplanktn at Skarsvag, N '\ ]ASHNOV (1939a) fund, at a crrespnding latitude in the western Barents Sea, a minimum f zplanktn in March and a maximum in August, and n secnd peak was bserved _ KONGSFJORDEN N ::'60 z 40 ::J...J > -'20 :! t-... ' ', I / J F M A M J J MONTH /' r------i.,.... ::. I' I \ /. \\ \ A 5 N Fig. 6. Mnthly mean ttal vlumes in ml/m ll f zplanktn at Kngs jrden, '\ Kngsfjrden (Fig. 6) The scarcity f samples frm this statin prevents a cmplete discussin f the seasnal variatins in the bimass f zplanktn. The spring increase started in June, but n general trend in the ccurrence f the

11 12 maximum was revealed. Hwever, high amunts f zplanktn were fund frm July, until the sampling was ended in Octber-Nvember. Up untiljune the main part f the zplanktn seemed t be cncentrated in the upper 50 m, but frmjuly nwards, the relative imprtance f the bimass f this water layer decreased steadily. Accrding t WIBORG (1960) the highest vlumes f zplanktn were fund during the last half f the year, bth in 1957 and PROPAGATIONS OF CALANUS FINMARCHICUS AT THE PERMANENT STATIONS, Sgnesjen (Fig. 7) The cmplete picture f the prpagatin f Calanus finmarchicus at Sgnesj0en is rather uncertain due t the scarcity f samples. Hwever, during all the years investigated there was a maximum f females at the end f February r the beginning f March, fllwed by high percentages f yung cpepdites during March. The main spawning evidently must have taken place in the first half f March. The percentage distributin f females, males, and yung cpepdites during the rest f the year indicates, as shwn in Fig. 7, that spawnings als tk place in early June and August. High percentages f the cpepdite stage V during summer and fall in the m samples, indicate that nly part f the spring generatin w 60! I- Z W u ffi J F M A M J J MONTH A s N Fig. 7. Variatins in the percentage distributin f males, females and cpepdite stages I-V f Calanus finmarchicus at Sgnesjeen. Mnthly mean figures

12 13 reaches maturity and spawns the same year, while the main part f the stck stays in the deeper waters as cpepdite stages IV and V until next spring. Three spawnings f Calanus finmarchicuj in castal waters f suthwestern Nrway have been recrded by several authrs (RUUD 1929, 'I RUNNSTROM 1932, GUNDERSEN 1953, and WIBORG 1954), and WIBORG culd even demnstrate that a furth spawning ccurredin WIBORG calls the spawning in March the "main spawning" and the later spawnings "minr spawnings", by which he prbably implied that, as stated abve, nly a part f the spring generatin takes partin the tw latest spawnings. Hwever, as WIBORG based his terms "main" and "minr" spawnings n percentages, they d nt reveal which f the spawnings actually was the mst imprtant because this will depend n the ttal number f animals present. In spring during the first spawning the stck is very small and, even if 100 percent f the ppulatin reaches maturity and spawns, the number f Calanus prduced may still be smaller than the number prduced by a lwer percentage f adults in the autumn when the Calanus stck is larger. The percentage distributin f the develpment-stages des nt therefre necessarily reveal the imprtance f the spawning. Hwever, the spring spawning at all statins was fllwed by a sharp increase in the zplanktn bimass (Figures 2-6) which indicates that the first spawning really is the main spawning in the sense f prductin f new animals llj 60 t- Z llj U ei 40 a.. 20 J F M A M J J MONTH Fig. 8. Variatins in the percentage distributin f males, females and cpepclite stages1-v f Calanusfinmarchicus at Skrva. Mnthly mean figures Symbls as in Fig. 7. A s N

13 14 Skrva (Fig. 8) During all the years investigated the maximum f females was fund in the middle f March, and the crrespnding cpepdite stages I andii ccurred frm the end f March with a maximum in the middle f April, which indicates that the main spawning tk place in the last half f March. A secnd peak f females ccurred in J une-july and high percentages f cpepdite stages I and II were present frm the middle f July, frm which ne may cnclude that a secnd spawning f Calanus finmarchicus ccurred in the first half f July. Fig. 8 indicates that sme spawning may als have ccurred in Octber. High percentages f the cpepdite stage V in the m samples indicate that nly a part f the spring generatin spawned the same summer. These results are in gd agreement with WIBORG (1954), wh stated that Calanusfinmarchicus at Skrva spawned in April-May and injuly August. He als suggested that a minr spawning must have ccurred in June. This suggestin was, hwever, built nly n the ccurrence f a small number f nauplii, and culd nt be fllwed thrugh the cpepdite stages. Eggum (Fig. 9) N samples frm March 1961 and 1962 are available, but the ccurrence f the cpepdite stages I and II in April bth years indicates that e UJ C!) 60 z UJ 0:: J F M A M J J MONTH A s N Fig. 9. Variatins in the percentage distributin f males, females and cpepdite stages I-V f Calanus finmarchicus at Eggum. Mnthly mean figures Symbls as in Fig. 7.

14 15 1 the maximum f females must have been in March, which was the case in A secnd peak f females was fund injune-july f all the three years investigated. Bth maxima f females were fllwed by high percentages f the cpepdite stages I and II. High numbers f yung Calanus finmarchicus were als fund in September withut a preceding peak f females. The material frm Eggum , may then lead t the cnclusin that there are tw spawnings f Calanus per year; ne in March and ne in June-July. The yung cpepdites fund in September may have been transprted int the area frm nearby ppulatins, as suggested by WIBORG (1954). Accrding t WIBORG there were three spawnings f Calanus at Eggum; in April, June and August-September. Hwever, als in this material the last maximum f yung cpepdites was nt preceded by a peak f females. Skarsvtig (Fig. 10) A maximum f females ccurred each year in March-April, fllwed by high percentages f the cpepdite stages I and II in April and May, s the spawning prbably tk place mainly in the first half f April. A secnd spawning ccurred in July, as high percentages f females were fund in July and the cpepdite stages I and II in August. High percentages the cpepdite stage V in the deeper water during the secnd spawning indicate that the spawning was f minr imprtance. 80 UJ 60 I Z UJ u ffi 40 Q. 20 J F M A M J J MONTH A 5 N Fig. 10. Variatins in the percentage distributin f males, females and cpepdite stages I-V f Calanusfinmarchicus at Skarsvag. Mnthly mean figures Symbls as in Fig. 7.

15 16 N previus investigatins n the prpagatin f Calanus finmarcllicus frm a cmparable latitude in Nrwegian waters have been made. Accrding t YASHNOV (1939b) and MANTEIFEL (1939) there is nly ne spawning f Calanus per year in the suthern Barents Sea and in the waters ff the west Murman cast. Hwever, accrding t MANTEIFEL (1941), cpepdite stages I-III are fund in sme years frm July t September in the Barents Sea withut a preceding abundance f adults. MANTEIFEL cncluded that these yung Calanus were brught int the Barents Sea frm Nrwegian castal waters, which supprts the cnclusin in the present paper that there is a secnd spawning in July in nrthern Nrway. Kngsfjrden The scarcity f samples frm this statin allws n cnclusins abut the prpagatin f Calanus finmarchicus. The material indicates, hwever, that there is nly ne spawning per year and that n spawning takes place in the secnd half f the year. DISCUSSION At all statins alng the Nrwegian cast there were tw prnunced maxima f vlumes f zplanktn per year, while K.ngsfjrden at Spitsbergen shwed nly ne maximum. There was a significant delay in the ccurrence f the spring maximum with increasing latitude, ranging frm April at Sgnesj0en t July at Skarvag. A similar trend fr the ccurrence f the secnd peak culd nt be detected. A cmplete cmparisn f the annual relative richness f the zplanktn frm the different statins was nt pssible because the material cllected during the winter seasn was t scanty fr Sme f the statins. Hwever, the material was fairly gd fr all the statins during the peride April t August, and in Table 1 is shwn the mean zplanktn vlumes fr the different statins during this perid f each year. Table 1 indicates the relative richness f zplanktn at the different statins during the perid April-August. Hwever, ne cannt draw any cnclusins abut the relative annual richness f the statins frm the table because the planktn bimass during the last half f the year is cnsiderably higher at Skarsvag and Kngsfjrden than at the ther statins. The ttal annual bimass per statin seems t be f the same rder f magnitude at the fur nrthern statins, while the bimass at Sgnesj0en

16 17 Table I. Mean f mnthly mean vlumes in ml f zplanktn per m 2 surface frm the permanent statins fr the perid April-August f the years Statin Year I 1960 I I Mean Sgnesj0en N data Skrva Eggum... N data SkarsvAg Kngsfjrden is cnsiderable lwer. This finding is supprted by earlier investigatins (WIBORG 1954, 1958, 1960). WIBORG (1954) fund that the richness f the zplanktn at Eggum during the spring and summer was cmparable t the cnditins at Gerges Bank ff the east cast f Nrth America and in the Barents Sea. During the winter the zplanktn density at Eggum and Sgnesjaen is extremely lw, and WIBORG suggests that the strng nrth-ging currents may carry the planktn away. The data d nt allw fr cnclusins as t which year was the richest because f the variatin frm ne statin t anther with n general trend. The data frm the permanent statins during revealed significant changes in the number f spawnings fr Calanus finmarchicus and the time fr their ccurrence with increasing latitude. At Sgnesjaen and pssibly at Skrva three spawnings were bserved, at Eggum and Skarsvag tw, and at Kngsfjrden nly ne. The spring spawnings ccurred in the first half f March at Sgnesjaen, in the last half f March at Skrva and Eggum, in the first half f April at Skarsvag and sme time between April and June at Kngsfjrden. A similar delay in the ccurrence f the secnd spawning with increasing latitude culd nt be detected. The spring spawning f Calanus was always fllwed by a sharp increase in the vlumes f zplanktn, and the maximum vlume was reached 1 1/ 2 t 2 mnths after the spawning. A similar increase in the vlume after the secnd spawning was less prnunced. This may be attributed t the fact that nly a small part f the stck f Calanus tk part in the spawning, that planktn is transprted int the area frm nearby regins, and that neritic species are much mre abundant during the late summer, reducing the relative imprtance f Calanus finmarchicus.

17 18 An attempt was made t determine the stage distributin f Calanus when maximum vlume ccurs. Althugh there are cnsiderable variatins frm ne year t anther, it is prbably permissible t cnclude that nlaximum vlume is fund when the cpepdite stages III and IV in suthern Nrway and IV and V in nrthern Nrway cmprise mre than 50 0/0 f the ttal number f Calanus. The relatinships between the stage distributin f Calanus finmarchicus and the ccurrence f maximum vlumes shuld be studied mre extensively, especially in breal ceanic waters where the dminance f Calanus is mre prnunced. The relatinship might enable us t determine frm a small number f samples the immediate future changes f the planktn bimass, which wuld be f main cncern fr the predictin f fd availability fr planktn feeding fishes. SUMMARY 1. Zplanktn has been cllected in vertical hauls frm 1959 t 1962 as fur permanent ceangraphic statins alng the cast f Nrway and ne frm Spitsbergen. The vlumes have been measured and the stage cmpsitin f Calanus finmarchicus determined. 2. A delay f ccurrence f maximum vlume with increasing latitude fr the spring maximum f vlume is evident, but a similar trend fr the secndary maxima culd nt be demnstrated. The annual richness f zplanktn n the suthernmst statin (Sgnesj0en) was cnsiderably prer than at the ther fur statins. At these the amunt f zplanktn was f the same rder f magnitude. There were large variatins in amunt f zplanktn frm ne year t anther at all statins, and a general cnclusin abut the relative richness f the different years culd nt be made. 3. A significant delay in the time f spawning f Calanus finmarchicus and decreasing number f spawnings with increasing latitude was demnstrated. 4. Maximum f vlume ccurred abut 1 / 2 t 2 mnths later than the spawning f Calanus finmarchicus when the cpepdite stages III and IV in suthern Nrway and IV and V in nrthern Nrway cmprised mre than f the stages. A methd fr predictin f bimass changesbased n develpment-stage distributin f Calanus is suggested. ACKNOWLEDGEMENTS The authr is indebted t Dr. K. F. WIBORG, Institute f Marine Research, Directrate f Fisheries, Bergen, wh rganized the cllectin and parts f the labratry prcessing f the zplanktn samples, and

18 19 wh kindly ffered him the material fr publicatin. Thanks are als due t Drs. K. BANSE and T. S. ENGLISH, University f Washingtn, fr valuable criticism and suggestins regarding the manuscript. The authr is currently n leave frm the Institute f Marine Research, Directrate f Fisheries, Bergen, Nrway, and the preparatin f this paper has been made pssible thrugh the curtesy f the Department f Oceangraphy, University f Washingtn, Seattle, Washingtn It cnstitutes cntributin N. 333 frm that institutin. This part f the wrk was supprted by funds frm Cntract Nnr-477(10), Prject NR , and Cntract Nnr-477(37), Prject RR betweenthe Office f Naval Research and the University f Washingtn. rj"q.. Og?> Oly- REFERENCES GUNDERSEN, K. R Zplanktn investigatins in sme fjrds in Western Nrway during Fiskeridir. Skr. Havundersk., 10 (6) :1-54. JASHNOV, W. 1939a. [Planktn prductivity f the suthwestern part f the Barents Sea.] Trans. Inst. Mar. Fish. U.S.S.R., 4: [In Russian]. 1939b. [Reprductin and seasnal variatins in the distributin f different stages f Calanusfinmarchicus f the Barents Sea.] Ibid., 4: [In Russian]. MANTEIFEL, B. P [Thezplanktnf the castalwatersf thewestern Murman.] Ibid., 4: [In Russian] [The planktn and the herring f the Barents Sea.] Plar Sci. Inst. Seafish. and Oceangr., 7: [In Russian]. RUNNsTRM, S Eine Uebersicht tiber das Zplanktn des Herdla- und Hjeltefjrdes. Bergens.i\lus. Aarb., 1931, (Naturv. R.), (7): ROOD, J. T On the bilgy f cpepds ff M0re Rapp. Cns. Explr. Mer, 56:1-84. WIBORG, K. F Investigatins n zplanktn in castal and ffshre waters f western and nrthwestern Nrway. Fiskeridir. Skr. Havundersk., 11 (I) : Quantitative variatins f the zplanktn in Nrwegian castal and ffshre waters during Ibid., 12 (1): Investigatins n zplanktn in Nrwegian waters and in the Nrwegian Sea during Ibid., 12 (6): Received 11 Nvember Printed 15 Nvember 1965.