1977_H27

._- - - - - - - - - - - - - - : - - - - - - - - "./
Thie paper not to be cited wlthout prior r8fere~ce to tAo author
InternatioAal Councll for
C.ld.1977/Ha27
the Exploration of the Sea
Polagic Piah Committeo
/Northern/
i
'-
by
•
Kazlmicrz Sludz1nski
Sen ~ishor1ea Inat1tute
Al. ZjedDoczen1a 1
81-345 Gd y D 1'a
/Poland/
The iRveatigationa on quantitative occurrenco'and distribution of herring larvao /Clupea hareDgUe
~L./
i. the North Sea
have boe. oonducted aince 1963 / W.Kijowski - 1963 1 - 1965,1966,
,
1967' P.Oiazewski - 1968,1969,1970, L.Szlachcikowska - 1971,1972,
1973, K.Sludzlnakl -,1974,1975/ with.the'purpoao ef watchi-s tho
•
chugoe to.klng placo ao regarda the populatlo11 dyltamics of herrillg~
Ichthyoplankton containing tho herring larvao was collect.d
during a cruiae of tho research vosael of the Fieheriee Institute, mt."Birkut". from 27 !b September to 2~ Ootober 1976.
During the above cruise thc obaervatlons were made at 56 etationa in tho area embracing the regions: Aberde•• , Plamboro and
Littl. Pitt.
Herrlng larvao were caugbt by tbe method oetabllsbed o. thc
meeting cf tbo Working Group leES in Lysokl11/SwGdo';, hold 1.
/
,
--2 -
May 1976. The plankton sample.r of the tYPI!ll "Gul! III" with the
eoniforme 1nlct of 20.6 cm 1n diameter was used. Tbe goarwas
sank at a speed of 50 m/min down to tho maximum depth of 100 m.
and at shallower stations - to 5 m over tho bottom. It waB take.
out at a speed of 10 m/min. Th. speed of trawliag was 5 kaots.
Th. whol. of tho material was preB6rved 1. 4
~
formal1_. thaa
horr1ng larvao were sepArated from othor plankton campo.ontse
Aftorwards they were moaoured with tho accuracy cf 0.5 mm aad
classifiod accordiag to tbeir body longth amd their aumber u.der
2 of tbe sea surfaco.
1 m
Herring larvao occurred in tbo above mentiaAed aron of tbo
•
Nortb Sea at 17 stations only. All the larvac wero fram tbo
.length range of moro'than 15 mm /Tabl. I/ with o.ly
tio.;
ODe
ODO
excep-
larva waD 14 mm longe
When oomparing tho qUaDtitatlve distribution of larvQo With
temperatures lt can be Doticod that larvao werG most numerouB
in watorD of temporaturea about 12°0.
A oimilar pattern of distribution, i.o., occurr••co' of groater numbersof-larvae in wator,of rolatively high temperatur.
/from 10 to 12oC/ wao oboerved in previous years i.veatigatioD • .
i.e •• 1974 and 1975 /K. Siudzinoki/.
Di
.....
_...e _----8
U·B Bio n
Roferrlag to the reaults
my resoaroh carried out i. previo-
~f
UB years /1974, 1975/. whcre I also had performod
aA
a.alysia of
Polioh invostigationa on tho occurreaco of horring laryae i. tbe
North Sea.i •••• aine. 1963 to 1975,i. 1976 a fall ia tho quaatity of
!
4t
- J -
1arvae was observed oBce more
iB the area 1.vest1gated. Ho.ever
the delayed start of research 1. 1976 does not al10w the author
to compare properly the results from 1976 with those from previous years.
\dC2&
.
ItVi8:ierally stated,.that i. 1976 there w..... exoept10.al11
deep fall 1. the .umber of herriag larvae. It was the first regress10• •i.ce 1971. Tbe i.dividuals caught were over 15 _
/but ••e larva of 14
•
•
JIUJl
1. leagth!_
l.ag
- 4 -
R • ~ e ren c • s
... --~-----Kijowski W.s
Wat~pna
analiza ilosciowego
aledzia w Morzu
P6~nocnym ~
wyst~powania
larW
latach 1963-1965
ImaszYBopis, Morski Instytut Rybacki - Gdynia 19661
~jowski
W.s
Morzu
Wyst~powaRie
larw slcdzia IClupea harengus
larw
iloBci~
~ormie
planktonu oraz
8led~ia
aa
w roku 1966. Ibidem 1967•.
P6~ocnym
Ciszewski P.: Opracowanie w
nad
L.I
aprawozdawczej WYAik6w badan
wpst~powanicm i
rozmioazcze.iom
w Morzu P6lnocnym w roku 1968.
Imaazynop1s, Morsk1 Instytut Rybaek1 - Gdynia 1968/.
C1szewaki P.s Produkcja zooplanktonu zo azczeg6lnym uwzglodn1eniom larw ryb uzytkowych Morza P61nocnogo i
8zol~
•
Coltyckie-
go. /maazYBopis, Morski Instytut Rybacki T Gdyn1a 1969/.
Ciszowaki P.: Produkcja zooplanktonu
p6~nocno-wschodniogoAtl~­
Bzczog6~ym
tyku /Morzo P6lnocno, Morzo llorwesldol zc
uwzgl~dnieniem
larw aledzia.
Imaszynopis, Morski Instytut Rybaoki - Gdynia 1910/,
8iudzinski K.s Quantitative distribution of horr!ng-larvao
/Olupea harengus
L.I
in tho North Boa 1n
1974~
IRternatioaal Oounoil tor tho Exploration of tho Boa,
. O.}J. 1975/H:32 Pclagic Fish Committeo - 1975.
Siudzinaki K.: Quaatitativo oeeuronoo of horring larvao /Olupca
hal'engus
L.I
in thc North Sea in 1975.
Intornatiomal Cou.oil tor tho
C.M. 1916/H&23
P~lagio
Exploratlo~
of thD
Sca~
Fiab Committoc /Northerx/ 1976.
Szlaoholkowska L.: Rozmloszozonie oraz stan ilosolowy larw ~lodzia na Morzu P61.ocnym w 1971 r.
/mas~y.opls, Morskl Instytut Ryback1 - Gdyaia 1972/.
•
- 5
Szlaohclktwska L.aRozmleszczeAle 1 ata.i1osciowy 1arw sledzla
w At1aatyku P61aoc.ym w 1972 r.
/maszy.opls, Morskl Iastytut Rybackl
.
Gdy.la 1973/.-
Szlachcikowska L.I RozmleszczeDie oraz .taa 11oscioW7 1arw 81edzla na Morzu POLDocRym w 1973 r.
/maszAopls, Korskl Iastltut Rybacki
•
•
Gdyaia 1974/•
...
- 6 -
Table I
Number of laryae caught at different stations of the North Sea
27.09 - 22.10. 1976
>
:STN
Date
No
27.09.76
993
27.09.76
995
996
28.09~76
. 28.09.76
997
998
28.09.76
1002 '
29.09.76 .
1012
08.tO.76
1015
09.10.76
1024
10.10.76
1025
13.10.76
1028
13.10076
1033 .. 21.10.76
21.10.76
1034
1035
21.10.76
1038
21.10.76
10.39
21.10.76
1041
22.10.76
Max.
Water
tow
dopth
No
filtcrod
catch
Im!
Im31
75
82
68
62
49
59
60
99
82
68
60
21
24
60
50
47
39
222
190
173
. 131
86
77
69
98
79
88
62
18
25
67
69
64
27
Herring larvae
1
5
4
1
1
1
1
1
1
1
1
1
1
1
1
1
2
No
~,
0,3
2,2
1,6
0,5
0,6
0,8
0,9
1,0
1,0
0,8
1,0
1,2
1,0
0,9
0,7
0,7
2,9
10-15
mm
0,4
) 15,
mm
0,3
1,8
1,6
0,5
0,6
0,8
0,9
1,0
•
1":0
0,8
1,0
1,2
1,0
0,9'
0,7 .
0,7 '
2.9
•