International Council for the Exploration of the Sea C.M. 1995/G : xx Ref.H Demersal Fish Committee PRELIMINARY REPORT OF THE INTERNATIONAL O-GROUP FI

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1 ntrnational Council for th Exploration of th Sa C.M. 1995/G : xx Rf.H Dmrsal Fish Committ PRELMNRY REPORT OF THE NTERNTONL O-GROUP FSH SURVEY N THE BRENTS SE ND DJCENT WTERS N UGUST-SEPTEMBER Th thirtis annual ntrnational 0-group fish survy was mad during th priod 16 ugust - _ - 8 Sptmbr in th Barnts Sa and adjacnt watrs. Th following rsarch vssls participatd in th survy : Stat Nam of vssl Priod Rsarch nstitut Norway "Michal Sars" nstitut of Marin Norway "Johan Hjort" Rsarch, Norway "G.O. Sars" Q7.09 Brgn Russia "Profssor Marty" Th Polar Rsarch Russia "tlantida" nstitut of Marin Fishris and Russia "Fridtjof Nansn" Ocanography, Murmansk Nams of scintists and tchnicians who took part on th diffrnt vssls ar givn ppndix. in th Prliminary analysis of th survy data wr mad on board "G.O.Sars" during th survy, and th final rport was finishd by corrspondanc. Obsrvations concrning th gographical distribution of 0-group fish and thir abundanc ar givn in this rport togthr with a brif dscription of th hydrographical conditions in th ara.

2 2 MTERL ND METHODS Th gographical distribution of 0-group fish wr stimatd with a small msh midwatr trawl. Four of th fiv vssls which participatd in th survy in, usd th typ of midwatr trawl rcommndd by th mting hld aftr th survy in 1980 (non., 1983). Howvr, th Russian vssl "Fridtjof Nansn" usd a trawl with 30 m vrtical opning, and unknown wingsprad. Two stps wr trawld to covr th usual 3 stp trawling. Th trawling procdur was standardizd in accordanc with th rcommndation mad at th sam mting. t about vry 30 nautical mils saild th trawl was towd in svral dpths in on haul. Th standard procdur consistd of towings of 0.5 nautical mil in ach of 3 dpths with th hadlin of th trawl locatd at 0, 20 and 40m. n additional tow at 60 and 80m for 0.5 nautical mil was mad whn 0-group fish layr was rcordd on th chosoundr dpr than 60m. procdur starting with th trawl in th dpst layr would probably b prfrabl. Th trawl would thn b "fishing" mor fficint troughout th whol trawl haul and maintain th corrct gomtry. t is rcommndd that this is furthr invstigatd. Hydrographical obsrvations wr mad along all th survy tracks with 5 to 40 nautical mils btwn stations (Fig. 1). Horizontal distributions of tmpraturs and salinitis ar shown for 0, 50, 100, 200m and bottom (Figs. 2-11). Figs show th tmpratur and salinity conditions along th Bar sland - Wst, Bar sland - North Cap, Kola and Cap Kanin sctions. Th man tmpraturs in th main parts of ths sctions ar prsntd in Tabl 1. Trawl stations with and without catch ar indicatd on th distribution charts in Figs , as filld and opn symbols rspctivly. Th dnsity grading is basd on catch as numbr pr 1.0 nautical mil trawling. HYDROGRPHY ccording to tmpratur conditions, is th 6. "warm yar" in succssion sinc Th man sa tmpraturs from m in th Barnts Sa in wr C abov th long trm avrag (1965-). Compard to 1993 th man tmpraturs in rangd from 0.1 blow to 0.6 C abov. Th maximum incras in watr tmpraturs from 1993 to was rcordd in th Bar cland - North Cap (0-200 m) and Kola (0-50 m) sctions. n th astrn Barnts Sa (Cap Kanin sction) watr tmpraturs wr C abov th long trm avrag and similar to thos obsrvd in n th Wst Spitsbrgn Currnt (0-200 m) tmpratur was 0.7 C abov long trm avrag. Howvr th distribution ara of tlantic watr was mor narrow than last yar and associatd with a dcras of C of th uppr mixd layr tmpratur to th north of 75 00'N. Tmpratur conditions in wr mainly dtrmind by a dcrasd tlantic inflow to th ara wst of Spitsbrgn and an incras inflow into th cntral parts of th Barnts Sa, south-ast of Bar cland, as compard with 1993.

3 DSTRBUTON ND BUNDNCE OF 0-GROUP FSH ND GONTUS FBRC 3 Gographical distribution of 0-group fish ar shown as shadd aras in Figs , and of Gonatus fabricii in Fig. 26. Doubl shading indicats dns concntrations. Th critria for discriminating btwn dns and scattrd concntrations ar th sam as usd in arlir rports (non., 1980). bundanc indics, stimatd as th ara of distribution with aras of high dnsitis wighd by 10, ar givn in Tabl 2. ll ara basd abundanc indics wr this yar stimatd by using standard computr programs (Fotland t al. 1995). nothr st of abundanc indics ar givn for 0-group hrring, cod and haddock (Tabl 3) calculatd according to Randa (1984). Ths ar basd on th numbr caught during a standard trawl haul of on nautical mil. Lngth frquncy distributions of th main spcis ar givn in Tabl 4. Hrring (Fig. 16) Small patchs with scattrd consntrations wr obsrvd wst of Spitsbrgn. Th main concntrations with thr small dns patchs wr found in th Cntral Barnts Sa, astwards to about 37 E. Th logaritmic abundanc indx is stimatd to 0,28 which is indicating that th yar-class is blow avrag during th priod Caplin (Fig. 17) ra basd 0-group indics wr givn in th yarly 0-group rports for th priod (non. 1980). t th nd of th lat 1970's th survy rsults indicatd grat variations in th abundanc indics, causd by variation in othr factors than 0-group abundanc ; as wathr condition during th survy. Thrfor, it was dcidd to xclud th abundanc indics for caplin from th futur rports. papr by Ushakov and Shamray (1995) givs abundanc indics for th priod Prliminary analysis of th rlation btwn th 0-group and th 1-group abundanc indics wr mad by Ushakov and Shamray (1995) and Gundrsn, Ushakov and Gjosxtr (). Thy concludd that th corrlation btwn ths variabls is positiv and highly significant. Th 0-group indx can thrfor, b usd to mak an yarly forcast of th yar-class abundanc at th 1-group stag, although, not vry accurat. On this basis th whol sris of indics is includd in th prsnt rport. s in group caplin was distributd in patchs in th Barnts Sa mainly with scattrd concntrations astward to Novaya Zmlya. Th -yar-class sms to b th third counscutiv poor yar-class. Cod (Fig. 18) Concntrations of cod wr rcordd in a similar ara as in Two dns patchs wr found wst of Spitsbrgn. Howvr, th largst ara with dns concntrations wr rcordd in th cntral Barnts Sa from about E and north to 75 N. Compard with 1993, whn 0-group was obsrvd astward to Novaya Zmbya, th 0-group was absnt ast of 48 E. Both th ara and logaritmic abundanc indics for th -yar-class ar th third and fifth highst rspctivly, classifying th yar-class as strong. This givs th fourth strong yar-class in succssion.

4 4 Haddock (Fig. 19) 0-group haddock was distributd in a narrow ara wst of Spitsbrgn. Th distribution in th wstrn part of th Barnts Sa was similar to last yar. Howvr, in 1993 th distribution in th Barnts Sa was mor to th wst and ast. Dns consntrations wr rcordd south of 73 N in, whil mostly north of 73 N last yar. Both th ara and th logaritmic abundanc indics ar th fourth highst sinc 1965, indicating anothr good yar-class, th fifth in succssion. Polar cod (Fig. 20) s in many arlir yars, th total ara of distribution was not compltly covrd. n contrast to 1993, a continuous distribution was rcordd from north of Spitsbrgn to Bar sland and astward to Novaya Zmlya. Th astrn componnt was vry rich, giving th highst abundanc indx rcordd, whil th Svalbard componnt was at a low lvl. Saith Only a fw spcimns wr caugth during th survy, indicating a patchy distribution with vry low abundanc. Rdfish (Fig. 21) Th south-wstrn part of th normal survy ara was not covrd in. Howvr, in gnral th distribution pattrn of rdfish was similar to thos in 1990 and prvious yars. Dns consntrations wr found wst of Spitsbrgn and in th astward currnt along th Norwgian coast. Th abundanc indx is highr than thos found in th priod , indicating a yar-class strngth clos to th avrag. Grnland halibut (Fig. 22) Scattrd concntrations wr rcordd in th ara btwn Bar sland and Spitsbrgn and off th wstcoast of Spitsbrgn. Th abundanc indx was dobbld compard to th 1992 indx, but still only half th high indics in th priod , indicating that th abundanc of th -yarclass is poor to mdium. Long rough dab (Fig. 23) Long rough dab was mainly distributd in th sntral and north-astrn part of th survy ara. Howvr, th ara of distribution was not compltly covrd. Two patchs with dns consntrations wr rcordd insid th rlativly wid distribution ara, and only th yar-class has a highr abundanc indx than th prsnt, indicating a rich yar-class. Sandl (Fig. 24) Sandl was mainly obsrvd south-wst of Novaya Zmlya, a littl furthr south than in

5 5 Catfish (Fig. 25) Catfish was distributd in th ara btwn Bar sland and th southrn part of Spitsbrgn and ast of Hopn sland. n addition small patchs wr found wst of Spitsbrgn and in th south-astrn part of th Barnts Sa. Only a small numbr wr caught in ach haul. Gonatus (Fig. 26) s in arlir yars, 0-group Gonatus fabricii was distributd in th wstrn part of th survy ara. Howvr, th ara of distribution was not compltly covrd. Survy catchs wr at th sam lvl as in REFERENCES non., Prliminary rport of th ntrnational 0-group fish survy in th Barnts Sa and adjacnt watrs in ugust/sptmbr nnls biol., Copnh., 35 : non., Prliminary rport of th ntrnational 0-group fish survy in th Barnts Sa and adjacnt watrs in ugust/sptmbr nnls biol., Copnh., 37: Fotland,.,Mhl, S. and Sunnana, K Mthods of indx calculation and prsntation of fish abundanc data using standard computr programs. 10 Pp. in Hyln,. (d) : Prcision and rlvanc of prrcruit studis for fishry managmnt rlatd to fish stocks in th Barnts Sa and adjacnt watrs. Procdings of th sixth Norwgian/Russian symposium. Brgn, Jun. nstitut of Marin rsarch, Brgn. Norway. [n prss] Gundrsn,., Ushakov, N. and Gjosatr, H.. Dos an 0-group indx giv rliabl forcast for yar class strngth of Barnts Sa caplin? Working papr to CES tlanto-scandian hrring and caplin Working Group, lopp. Randa, K bundanc and distribution of 0-group rcto-norwgian cod and haddock Pp in Godo,O.R. and Tilsth,H. (ds.) : Rproduction and rcruitmnt of rctic cod. Procdings of th first Sovit-Norwgian symposium, Lningrad, Sptmbr nstitut of Marin Rsarch, Brgn, Norway. Trshchnko, V.V Som rsults from long-trm ocano-graphic obsrvations during 0-group survys in th Barnts Sa. CES CM 1992/C :18. Torsn, R Rcruitmnt indics of Norwgian spring-spawning hrring for th priod basd on th intrnational 0-group fish survys. CES CM 1985/H : 54. Ushakow, N.G. and Shamray, E Th ffct of dffrnt factors upon th Barnts Sa caplin yarclasss. 24 Pp. in Hyln,. (d) : Prcision and rlvanc of prrcrutit studis for fishry managmnt rlatd to fish stocks in th Barnts Sa and adjacnt watrs. Procdings of th sixth Norwgian/Russian sympo ium. Brgn, Jun. nstitut of Marin rsarch, Brgn. Norway. [n prss

6 Tabl 1. Man watr tmpratur' in main parts of standard sctions in th Barnts Sa and adjacnt watrs in ugust-sptmbr Yar Sction 2 and layr (dp in mtr) bot. 0-bot vr " Earlir prsntd tmpraturs hav bn slightly adjustd (Trshchnko, 1992). 2> 1-3 : Murmansk Currnt ; Kola Sction (70 30'N-72 30'N,33 30'E) 4: Cap Kanin sction (68 45'N 'N, 43 15'E) 5 : Cap Kanin sction (71 00'N 'N, 43'15'E) 6 : North Cap Currnt ; North Cap - Bar sland sction (71 33'N,25 02'E 'N,20 46'E) 7 : Wst Spitsbrgn Currnt ; Bar sland - Wst sction (74 30'N, 06 34'E 'E)

7 7 Tabl 2. bundanc indics of 0-group fish in th Barnts Sa and adjacnt watrs in Wst Polar cod Yar Caplin' Cod Haddock Rdfish Grnland halibut Long rough dab (26) East ~' ssssmnt for in non and for in Ushakov and. Shamray

8 8 Tabl 3. Estimatd logarithmic indics with 90% confidnc limits of yar class abundanc for 0-group hrring, cod and haddock in th Barnts Sa and adjacnt watrs Yar ndx Hrring Cod Haddock Confidnc limits ndx " ssssmnt for mad by Torsn (1985). Confidnc limits ndx Confidnc limits

9 9 Tabl 4. Lngth distribution of 0-group fish in prcnt in th Barnts Sa and adjacnt watrs in ugust - Sptmbr. Lngth (mm) Cod East Polar cod Wst Hrring Caplin Haddock Rdfish Grnland halibut Long roug dab Sandl No. masurd Total numbrs Man lngth

10 10 0, 1,,, i,,,,,,,,,, 1 17 UG - 8 SEP Z CTD Sond station. s3 ll Fig. 1. Survy tracks and hydrographic stations.

11 11 0 i i, i f4 CC OM Zdl xj ct 1 Fig. 2. sothrms at 0 m.

12 12 5' 10' 15' 20' 25' 30' 35' 40' 45' 50' 55' 80' O L.r'Q O. 79' S Om 78' * - 75'- TV - i ' '-70* 69'- 68* 67 3~0 C y~ ,~ Fig. 3. sohalins at 0 m.

13 13 5' 10' 15' 20' O 25' 30' 35' 40' 45' 50' 55',-G rj '3 0.9 oq t'c 50m 1 \N O ~~ --/5 G 7 n 0 4.p 4 Fig. 4. sothrms at 50 m.

14 14 80' - 5' 10' 15' 20' 25' ) 30' 35' 40' 45' 50' 1 55' -~ / 79' - 0 G- S 50m 78' - 77' - 76'- 75' - 74! \ ,. 34 /315.0 P ~/ ' - ~ 35.0 \J V '-7(7-69' 34. n ~, ' - 67 Fig. 5. sohalins at 50 m.

15 15 80'- 5' 10' 15' 20' 25' 30' 35' 40', 1, 1 1 1,, 1, 6 `5 45' 50' 55' J,, 79* - t'c 100m 4 78'- 77* - 76' - 75' ' '-T0' U. n b s /10 5 ' i )J i 1 1 1, r j , Fig. 6. sothrms at 100 m.

16 ' 10' 15' 20' 25' 30' 35' 40' 1 lilt] ] it 11ltl~ fill i i o ~ 55' uq a. 79' S 100m 78' " - 75' - 74' ' O 73' * - 71' - CJ35' St (7- ~ Q '- 6T `x \4. Fig. 7. sohalins at 100 m.

17 Q.10 Q o 0 G- t C 200m SV G4 4 r-2 &d 4 Fig. 8. sothrms at 200 m.

18 18 5' 10' 15' 20' 25' 30' 35' 40' 45' 50' 55' i iii ; O &p Q t..',8 4 S 200m ' - L ' ' * - 72' - 71' V1 O ~,-j - x ^ ~~ J~" x * * - 67 Fig. 9. sohalins at 200 m.

19 t, 19 5' 10' 15' 20' 2 4 O 80' - 25' 30' 35' 40' i 1 55' ~ QO 79' - 4p- t'c at bottom 78' - 77' - 76'- 75* G -1 C, J-, 73' '-70' / \ c3 _7\ ~ b J% ' - 68' - 67' 4a. 4D 0 4q Fig. 10. sothrms at th bottom.

20 20 i 1 i i i t 1 i ) Q l i l l l t i i l i l t l i~ l i i l S at bottom 3Q O C L t 35.0 L /35.0 ^~ X \ i E- 5 to Fig. 11. sohalins at th bottom.

21 'E 6'34'N 74'30'N 18'30'E '30'E 6'34'N B 74!30'N 18'30'E Fig. i2. Hydrographic sction Bar sland - Wst. Tmpratur () and salinity (B).

22 22 74'14'N 19'20'E 71'26'N 25'29'E '1 4'N B 71'26'N 19'20'E 25'29'E Fig. 13. Hydrographic sction North Cap - Bar sland. Tmpratur () and salinity (B).

23 23 76'00'E 33'30' N 69' 32' N 33'30'E 76'00'E 33' 30' N B 69'32'N 33' 30' E Fig. 14. Hydrographic sction along th Kola mrdian. Tmpratur () and salinity (B).

24 '30'E 43'1 5' N 68'45'N 43'1 5'E Fig. 15. Hydrographic sction Cap Kanin - North. Tmpratur () and salinity (B).

25 25 20' 25' 30' 35' (,~ GROUP HERRNG P fish pr. n. > 1000 fish pr. n. mil mil l l l l a o l L a a - 1 UR,V4 d b'j m m ~/ ~~ m 44 o. l l Fig. 16. Distribution of 0-group hrring.

26 26 5' 10' 15' 20' 25' 30' 35' 40' 45' 50' i 55' 80' - o o 0-GROUP CPELN nq /~ 79' fish pr. n. mil > 1050 fish pr. n. mil 78! - 77' -- i o 76'- 74! - -- l o /'~ l _ /~ o l p / l /~ L o 75'- 73' - 7Z- m ~~ P 71'-70*,, - ~ 4s `~~ ~ / 69' - f 4,.'' P 68'-. 67 Fig. 17. Distribution of 0-group caplin.

27 ' GROUP COD V 1-85 fish pr. n. mil > 85 fish pr. n. mil r- --- c nc n it 4O. 411 Fig. 18. Distribution of 0-group cod.

28 28 5' 10' 15' 20' 25' 30' 35' 40' 45' 50' 55' a O qzq Qo 0-GROUP HDDOCK t6 a 1-85 fish pr. n. mil > 85 fish pr. n. mil p o, ~ l, m 1 1 cfb U c m 4 1 Fig. 19. Distribution of 0-group haddock.

29 29 7Y- 72'- a 71 ' - m m 70' * - 68' - Fig. 20. Distribution of 0-group polar cod.

30 30 5' 10' 15' 20' 0 25' 30' 35' 40' 45' 50' 55' 0,9 0-GROUP REDFSH 1-85 fish pr. n. mil > 85 fish pr. n. mil o 1 l ~ l l l - n l a l o ~, m \~ ~ o m 4 ~~ `b - _ Fig. 21. Distribution of 0-group rdfish.

31 a , O 20' 25' 30' 35' 40' 45' 50' 55' 0-GROUP GREENLND HLBUT d~* 1-85 fish pr. n. mil 7T---1 a 74'- 73' - 70'- 76* a a a a 6 a a L, a a o a a a~ a a a~ a a a a p a a a l -- a a a a a1 a a a l --- a a a a a a s L J am a l a a a a a a s a s a s a a a a a a a a a as a s a s 1 a a s a a m a a a a a a a a a to a a a a a a a a a 6 m a a a a a 5' 0 a o a a a a ~-% 4 m 4 a,> a a a a Fig. 22. Distribution of 0-group Grnland halibut.

32 32 5' 10' 15' 20' 25' 30' 35' 40' 45' 50' 55' 4 0-GROUP LONG ROUGH DB 0 i 1-85 fish pr. n. mil > 85 fish pr. n. mil - 1 L 4 2 Fig. 23. Distribution of 0-group long rough dab..

33 33 45' 50' 55' Q,oV Q ~Q O 0-GROUP SNDEEL Gb 1-85 fish pr. n. mil > 85 fish pr. n. mil l L p ---- n ~ 1 l 1 _ l j n c n c~ L---~ Do 1 1 m 44 m rc,, a0 N ^~ a o G l -% q an 1 Fig. 24. Distribution of 0-group sandl.

34 34 80' 20' 25' 30' 35' 49 45' 50' 55' i J ~.04 3QOG 0-GROUP CTFSH 79' fish pr. n. mil 78' - /f 77 76'- 1 ~ 75' '-7T-71'-7C' 1 l l n n c n 69' - 4 4n 68' - 67' Fig. 25. Distribution of 0-group catfish.

35 35 20' 45' S0' 55' 71 4 Q c o 0-GROUP GONTUS 1-85 fish pr. n. > 85 fish pr. n. mil mil n--o -- n, 1 l \ c~ b Z? m m o m 4 1 4n - o, Fig. 26. Distribution of 0-group Gonatus fabricii.

36 36 PPENDX Rsarch vssl Participants "G.O. Sars" V.nthonypillai, H.Hammr, J.Hamr,.Hyln, L.Kalvns, H.Larsn, E.Molvar,.Rakns, K.Stromsns,.Slott, N.Ushakov (PNRO). "Michal Sars" "Johan Hjort" "Profssor Marty" "Fridtjof Nansn" "tlantida" B.K.Brntsn, T..Halland, K.Korsbrkk, T.Mork, J.E.Nygaard. J.d Lang, P.Fossum, H.Grasdal, S..vrsn, E.Mland, O.Nakkn, O.Navdal, R.Pdrsn,.Romslo, U.Schaur (Tyskl.).(Grmarr y). V.Chixhikov, M.Ermolchv,.Nikiforov, D.Prozorkvich, S.Ratushnyy, E.Shamray, E.Trshchnko,.Vakulnko, N.Vovchuk..Badigin, S.Boichuk, S.Gotovtsv, T.Srgva, V.Tataurov, S.Ustinov, T.Yusupov..Dolgolnko, T.Gavrilik, V.gnashkin, V.Mamylov,.Pdchnko,.Sagaydachny, V.Trtjak, V.Zhuk.