..
leES STATUTORY MEETING 1993 C• M. 19931M: 1 6 AnadromouB and Catadromous -Flah Committee Ref.J. .'
PRESENT SITUATION OF THE VISTULA SEA TROUT
by / R.Bartel Inland Fisheries Institute River Fisheries Laboratory Reduta Zbik 5. 80-761 Gdanak. Poland
ABSTRACT
The alm of the paper wan to show a present status of ViHtula !H~a trout. Pollution of water .in t.he Vistula River llave brought to reduce population of Yistula sea trout. Wllen Hle Vistula River was dammed in 1969 Yistula sea trout population drasticaly dropped. In
1972.-199c. there were released into the Yistula River from 3~0 000 to 314 000 smolts and from none to 446 100 alevins, yearly. In t111s period the sea trout catches in the Vistula River varied from
30.9 to 12.9.1 t ..Effectivenes of Btocking based ~n sea trout • catches in the Yistula mOl1th and the Vistula River was in average c.95.5 kg/lOOO smolts. C. ~1.1993/t·1: 16 ICES STATUTORY NEETING 1993 Anac~t Fish.Comm Ref.J
PRESEHT SITUATIO~OF THE.VISTULA RlVER SEA TROUT
Ryszard Bartel
Inland Fisheries Institute in Olsztyn River Fisher~eß Lab?ratory in Gdartsk
i. Introduction • Vistula river, the blggest Pollsh river, had in the past and still has the biggest popUlation of the se;:ltrout. A steady
process of the environment degr~dation, and in concequence
worsening of water quality in the Vistula's main stream ehannel as
weIl as in the tributary rivers, resulted in a gradual decreRse in
catches of fish, also migrating ones, and then in elosing down of
fisheries cooperRtives 0perating in the upper Rnd middle ViRtula
wRters. The following fisherjes cooperatives were cloRed down: in
Krak6w in 19~8, in Wyszogr6d in 1968, .in TarnObr7.eg in 1971 ~nd in ePlliRWY in 1976 (Wisniewolski, 1978; Fig.I),·
The other evident proof of worsening of ecological situat.ion
in the Vistula river is a decreasing number of the sea trout
spawners on the spawning grounds in the Vistula's upper tributary
rivers. The very last sea trouts were caught in Sola in 19~6, in
Raba in 1957, in Dunajec in 1968 (Bieniarz, ~ysak. 197~; Fig. 1),
The fact of catching of the last sea trouts in Dunajec river
coincided with construction of the dam in Vistula Rlv~r , in
W}oc}awek, Though this dam has a fish pass but the latter does not
fUlly comply with the requirements as only limited number of
individuais of sea trout passes above it and only single - 2 -
individuals are caug~t in vicinity of Nowy Dw6r and Pulawy
(Bartel , Zieli().ski, 1991).
The recent observations of sea trout migration, by means of
sonic tagging (unpubl ished material S of InRt.i t'lt.e of the Russian
Ac~demy of Scienees at Rarok and of the Inland Fisheries Institute
in Gda().sk) proved that the sea trout had difficultles in finding
the entranee in the fish pass positioned in the dam in Wloc}awek.
Eeologieal degradation as weIl as the influence of the
barriers eonstrueted in river's streams, hindering or making it
even impossible for the spawners to reaeh the spawning grounds,
have been observed in the Vistula river and some other Polish 4t
rivers (Fig.l). Positioning of the dam in the Vistula river in
Wloelawek resulted in a eonsiderable decrease in number of smolts
migrating from the Vistula eatchment area down to .the Baltie Sea.
The number of these smolts, estimated in the 50's and at beginning
o f the 60' s, thus prior the other effects, namely state of the
environment and dam eonstruction, was on the level of 500 thous.
to million (Backtel , BarteI, 1967), while at the present time,
it is not higher than about 30 thous. After the dam construction
·aeross the Vistula river in Wloe}awek the river Drw~ea remained
the single bigger tributary river having the conditions for
nat.ural spawning of the sea trout. Though its potential
possibilitiel'l underwent limitations resulting from pollution
prOblems and construetlon of artifieial barriers aeross Drw~ea's
tribl1tary rlvers, the role of thil'l river, with respect to
population of Vistula river sea trout, is essential, aB it favours
an inerease of the genetjc variability of Vistula SBa trout
pO~11ation due to the fact that the fish spawns in natural
conditionR. BeBtdes, in Drw~ca there spawn the sea trouts
represent.lng winter popülat.ion (Borz~eka,. personal communieation). - 3
The importance of sp~wning of winter sea trout in Drw~ca riv~r
should be emphasized as the rearing of smolts of this particular
sea trout is not carried out at present.
The aim of this worK IR to present the Vistula sea trout
management in the recent years.
Z. Materials ~d methods.
Materials from the "Information Service on Salmon Management"
initiated in 197e and iRsued in the form of manuscripts of the
Inland Flshery Institut~, Rupplem~nt~d with m~terials from the i9~ • "Gospod~rka (R~rtpI, R~rtel~ Rybna" 19766 Zielirtski, 1977, 1978, ,~lj6 >i",-,b,.l gÖCL1.1b, ~'3 B 1~,b,--t'3 M. IIBlI 1979,{~8"11982, 1984\1and wlth the materials collected for the "-I"'). rii'jnie wol ... ki '50 Ll&!c("("j~~1)/' "Information S~rvic~ "but not. published - w~re llsed to prepare
this pap~r.
Construction of Vistula dam In W}oc}awPK c~uRPd changl" in
fish~ry relations in the Vistula river. This ch~ng~ fOllnd its
~ reflection in catches of migrating species such as vimba and sea
·.{rout. Catches of the latter species increased below the dam whil~
dropped nearly to zero above the dam (Fig.2 Sych, BarteI, 197Q). tho!? The decre~sing number of smolts inVVistula has been observed
mllch ~~rlier and ther~fore the attemptR w~remade to replenish the
unR~tisfactory Vistula trout's spawninq by stocKing with the parr
reared in hatcheries. As the number of eggs obtained from th~
ViRt\lla t.rout. was not suffieient it was d~eid~d that the
Vlstu]a eatchment area would be stocked with the material reared
from eggs originating from th~ R~a troutB of Pomerania rivers.
Though the number of r~ared atocKing indiy.iduals,· released in - 4 -
the ViRtul~ catchment area was continually increasing it did not
find itR ~eflection in tti~ Rea'tr6u~ catches. O~the contrary,
beqinning from the l~te 70's, a steady decrease of catches of sea
trout in Vlstula and ItR estuary, has heen ohserved (Fig.3). Lack
of effects of stocking lied in the fact of preference of stocking with parr and presmolts.
Elimination of the stocking material originating in Pomerania
rivers, from the ViRtul~ stocking, decreased the possibility of
stocking with reared smolts and the crossing of the Vistula with
dam in Wloclawek almost entirely excluded the upper Vistula triblltary rivers from n~tural spawning. In conRequence there was 4t danger of drastic decrease in sea trou~ population in Vistula.
Some hope for improvement of the situation appeared when in 1967
some basins, provided for keeping the Rea trout spawners, were \!)(oS'>(\.kc.,;;ki .~jC·!lt open for exploitation at Swibno in Vistula estuaryv:That enabled
obtaining the eggs of Vistula trout for smolts rearing. ThP
importance of this object singnificantly increased when the
Fishery Cooperative "Certa", fishlng below the dam in Wloclawek. relinquished obtaining of the eggs in 1985. In the years 1972-1984 this Cooperatjve obtained 4.270.000 eggs from spawners kept in @"-fi~l.~I:3IiJ1'jj.Jd . ~18 -\'!1~ -1~~·1 ,(032~, 1'1SG'1~Z;"""h -j'1ZC ... ,b A~gr_: • earth ponds in Nies~Bartel, Zfelinskr;'19"m. I It can bp said that t.he present stat.e of Vistllla t.rout population is the re!'!ult of two positive fact!'! - the presence of basins in Swibno and the stocKin~ with smolts reared from eg~s ori~inating from the
.~pawners call~ht in the Vistula pstuary.
Number of eggs procured by the Fishery Cooperative in Swibno in the recent cO years ranged from 181.000 in 1979 to nearly
2.000.000 in 1992. while numbpr of smolts released in the same time to Vistul~'s catchement area ranged from 3P..OOO in 1985 to
314.300 in 1990. Number of rel~~Bp.d B~olts to Drw~ca in the years - 5 -
197e-19ge fluctuated from zero in 1973 and 1974 to 128.000 in 19QO
and number of released fish in Vi'stula estuary varied from zero in
1975 to 186.300 smolts in 1990 (Fig.4). Besides, certaln numbers
of trout alevin were released into the Vlstula rlver.
The numbprs of released smolts werp affected not only by the
number of obtained eggs but also by the breeders competence in
" rearing' andtheir willingness to produce the stocking maie~ial. -
The breeders' skills have continually been improving while thelr
inclination to real' the smolts was connected wlth the flnancial
abilities of the CommiRslon for Stocking and Salmon Management.
the latter strictly depending on finances allocated hy thp
Ministry' of Agriculture. Ministry of Transportation and Maritime
Economy and the Minlstry of Environment Protection. Some
insignificant funds were provided by the fishermen catching the
sea trout, and by some Provincial Councils.
In the conRidered period t97e-1991' the sea trout catches in
the Vistula river, between its pstuary and Wloclawpk. ranged from
30.9 tonnps in 19841.0 1e9.1 tonnes in 1990 (Fig.~). At the same
t.ime the numher of Rmolt.R, migrat.in!! t.O the sea fluctuat.ert from
74.000 in 10B~ to 348.000 in 1000 (Fig.5). 1'he number of smolt.s, • showed in Fi~.5 represent the :following ccmponents: t.he number of smolts reared in the hatcheries, the number of released alevins
recalclllated for number of smolts. assuming 1% survival, and the .~ nllmber cf smolts from natural spawninR. The very last component
was assumed to be a stable value, equal of 30.000 in each year.
Fig.5 E1hows a constderable dependence of trout catches in the
Vistula river upon stockine. In order 1.0 make the comparison more
readible, the curve representing number of smolts migratin~ down
1.0 the sea was shifted by 1 year as the sea trouts are mainly
caught in the second and third year after stocking(BaCkiel~ 6 -
Bartei, 1967) . The dependenee of these two parameters is evident
(Fig.6).
F.ffectiveness of Vistula stocking, expressed by the size of
sea trout eatch (in kg of 1000 smolts) was equal of 295.5 kg, at.
the t.otal Cnteh, in the yenrs 1973-1991, amonnt.ing to 1 000 344 5
kg and at the number of smol.ts, in the years 1972-1990, being
equal 3 385 400.
In order to serve the investigating institutions and for the
purposes of fishery cooperatives, eatching the sea trout between
5wibno and W}oc}awek - it. is essential to know the s1ze of catches in particular seetors of the Vistula river. • Thesea trout catches in Vistula river and its estuary ranged
from 30 931 kg in 1983 to 129 070 kg in 1990 (Fi~.7) , with the
yearly mean - 50 639 kg. The big~est total amount of fish was
cau~ht by the Cooperative in 5wibno: thejr average was 40 561 kg
with extremes - 18 628 kg in 1972 and 107 700 kg in 1990 (Fig.7).
The share of the remaining Cooperatives was considerably lower and
wit.hin this grollp the leartinR was Cooperative in Tczew; their
average was 5 211 kg with fluctuations from 1356 5 kg in 1980 to
15 200. kg in 1990 (Fig.7). The fishermen operating below the dam.
in W}oc}awek caught on average 3 989 kg with exremes - 600 kg in
1987 and 13 105 kg in 1975. The fishermen from vicinity of
Bydgoszcz had as low as 3 kg catch in 1977 and 4957 kg in 1974
with agp.rage being on the level of 1439 kg (Fig.7). Th~ shar~ of
particular Vistula regions in catches of trollt Is hf"tter
illustrated by catches expres~ed in percents. In the years
1972-1991 Swihnl) nbt.ained 80.1% of total t.rout biomass. The 10wp.Rt
Rhal"e in total trout biomass 5wibno had in 1972 - 59.9% and the
highest, reaehing 90.91., was observed in 1980 (Fig.8) .
. considerably lower share, only 10.3%, had flaherman from
· .. _....,.-.... .:.,... " - 7 -
Tczew. 'T'heir sl1are in trout catches in p~rticular years ranged
from 3.81. in 1980 to 24.11. in 1972 (Fig.8). The f1shermen from
BydgoR7.cZ caught on average 7.91. and 2.81., respectively.
In contrast, the share of Drw~ca was insignificant and the
maximum catch reached 1400 kg while minimum was zero; in some
cases there was lack cf information. These catches include fishing
with rods, professional catches and catches of spawners.
To sum up the following conclusions can be drawn:
1. Stocking with the sea trout smolts in the Vistula r1ver estuary
and in Drw~ca should be carried out in order to maintain the • trout. popul~tion at the proper level. ?. In order to· ~ssure an adeqllate amount of sea t.rout· eggs
provided for smolt.s rearing - there must be remained the BasE'
for Spawners in 3wibno and 1t should provide 2 million eggs
every year. At the same timE' there ShOllld be obtained from 0.5
to 1 million eggs a year from fish in Drw~ca.
:3 • There shonld be continned compli~nce with avoidance of
introduction of Pomerania Sea trouts to Vistula catchment area.
4. The attention should paid to the fact that wh1le stocking with
alev1n of brown trout there shonld not be introduced a mixture • of sea trout and brown trout or1g1nating 1n hatcher1es having stocks of brown trollt sp~WneT'A build up on a b;:l~(! ()f adm1xture
of the sea t.T'ont..
5. Preservation T'f'i'gulat.lonR Rhollld be respect.E'd to enable the-
migratlng sea trout to reach the spawning grounds.
/Translated by Mrs. M.Postuszok/ - 8 - .
Referenees
Baekiel T. end R.8artel 1967. Oefektaeh .. zarybi.ania smoltami troei na tle wynik6w.ieh znakowanis'jOn e~feets of st~eking .with sea trout smolts es the results of their te9gin9/. Roez.Nauk Roln. ser.H,90,3:365-388. Bartel R. 1976. Gospodarka lososiowa w Polsce. Cz.II /The salmon fishery in Poland/. Gosp.Ryb. 28,8:14-18. Bartel R. 1989•. Gospod~rka troe~owa w Polsee - stan obeeny i perspe kt~wy. /5ea t~out husbandryin Poland:~ the present state and prospeets/. Gosp.Ryb. 41,10:3-7. Bartel R. and Z.Zieli~ski 1977. Gospodarka ~ososiowa w Polsee w 1974 roku /The salmon fishery in Poland in 1974/. Gosp.Ryb. 29,8:9-15.
•. Bartel R. end Z.Zielinski 1978. Gospodarka ~oSosio~Na VI Polsee w 1975 roku /The salmon fishery in Poland in 1975/. Gosp.Ryb. 30,6:11-17. Bartel R. and Z.Zieli~ski 1979. Gospodarka lOGosiowa w Polsee w 1976 roku /The salmon fishery in Poland in 1976/. Gosp.Ryb. 31,10:11-17. Bartel R. end Z.Zieli~ski, 1981. Gospodarka ~ososiowa w Polsee w 1977 roku /The salmon fishery in Poland in 1977/. Gosp.Ryb. 33,4:11-18. Bartel R. and Z.Zielinski, 1982. Gospodarka ~ososiowa w Polsec w 1978 roku /The salmon fishery in Poland in 1978/ Gosp.Ryb. 34,4:10~17. Bartel R. and Z.Zieli~ski 1984. Gospodarka lososiowa w Polsee e w 1979 roku /The salmon fishery in Poland in 1979/. Gosp.Ryb. 36,11/12:18-24. Bartel R. and Z.Zieli~ski 1985a. Gospodarka lososiowa w Polsee w 1980 roku /The salmon fishery in Poland in 1980/. Gosp.Ryb. 37,4:4-10. Bartel R. and Z.Zielinski, 1985b. Gospodarka lososiowa w Polsec w 1981 roku /The salmon fishery in Poland in 1981/. Gosp.Ryb. 37,10:3-7. Bartel R. ,and Z.Zielinski 1986a. Gospodarka lososiowa w Polsee w 1982 roku /The salmon fishery in Poland in1982/. Gosp.Ryb.38,7:5-11. - 9 -
Bartel R. and Z.Zieli~ski, 1986b, Gospodorka lososiowa w Polsee ~·1983 roku /The saloon fishery in Poland in 1983/. Gosp.Ryb. 38, 11/12:5-11. Bartel R. end Z.Zielinski 1987a. Gospodarka ~ososio~a w Polsec . w 1984 roku /The salmon fishery in Polend in 1984/. Gosp.Ryb. 39, 7/8:9-14. Bartel R. and Z.Zielinski 1987b. Gospodarka lososiowa w Polsee w 1985 roku./The salQon fishery in Polend in 1985/. Gosp.Ryb. 39, 11:5-11. Bartel R. and Z.Zielinski 1989. Gospodarka·lososiowa w Polsee w 1986 roku /The salmon fishery in Poland in 1986/. Gosp.Ryb. 40, 4:5-11. Bartel R. and Z.Zielinski 1991. Sprawozdanie z "Ser~isu" gospodarki lososiowej w Polsee za1987 rok /Report from the • "Service" of the.salQon fishery in Poland for 1987 I~st.Ryb.~r6dl~d~ Olsztyn/ma~useript/. Christensen 0., N.Joh9nson, 1975, Reference report on 8altic Salmon with additional information on Baltic sea trout. ICES, Cooperative Research Report 45. Kossakowski Z. ,1969, Gaze torlakowa w ~wibnie. /Bosins for see trout spawners in SWibno/. Gosp.Ryb. 21,4:3-5. Sych R. and R. Bartel 1979. i-todel matematyczny gospodarki loscsiowej na Baltyku. Mi~dzynorodowc Sympozjum ~~rikultury /The mathematical model of the salmon fishery in tho 8altic. Internotional·Marieulture Symposium/, Her.Inst. Ryb., Gdynia, listopad 1979 /paper/. ~i~nioweiski W., 1987, Gospodareze polowy ryb w ~i~lo, Odrzc i ~arcie ~ latoch 1953-1978 /Commcreial eatches of fish• in the Vistula, Oder, and Warte in 1953-1978/. Rocz. Nauk Roin. 101,ser.H,2:71-114. ..
•
----A '.-B ''>\ (d) C
Fig.l. Sea trout rivers in Poland, posibilities to reach spawning grounds /Christensen, ~ohansson 1975 modyfied/ A- et present; B- in the post, C- adam in Wloclawek built in 1968, 1 - Pasl~ka River, 2 - Bauda R., 3 - Narusa R., 4 - Vistula R.
4.1 - Sola R., 4.2 - Skawa R., 4.3 - RudawD R., 4.4.- Raba R. I 4.5 - Dunajec R., 4.6 - Wisloka R., 4.7 - DrwQca R., 4.8 8rda R., 4.9 - Wda R., 4.10 - Wierzyca R., 5 - Reda R., 6 -~eba R., 7 - ~upawa R., 8 - Slupia R., 9 Wieprza R., 9.1 - Grabowa R., 10 - Uniesta R., 11 - Pars~to R., 11.1 - Ra dew R., 12 - Rega R., 12.1 - Molstowa R., 13 - Gowienica R. ~. 14 - Odra R., 14.1 - Ina R., 14.2 - Warta R., 14.3 - Wclna R., 14.4 - Notec R., 14.5 - Drawa R., 14.6 - Plociczna R•• 14.7 - Gwda R. - -, ------
.Average yeDrly ~ütcha~ of ses traut in th~ Vistulo Rivcr /tonnt:ls/
N befaro &.ft e r c r 0 S ~ l ng • wi th a r.bm ....:E 0_ n0 o n n (j). c .... ~ , III Cl) , 33,3 12,9 ~ n \1) 11 , :J T:' 0 n c: C'J '" rot -<(J) ...... ,.,0 n :J ::T rt < ::r ~. m
~ ~ lO , c: Cl) rt ..... Cl m tl .... rt 0" ., ~ 0 ...... C \0 0 rt 14,7 0,006 -..J ~ \0 '" QJ • :JC. ..< üccurenCD of tho 5CU CU t.1 sYStl4j~i CT rt traut in Vlstula o C < .... ~ '" rt UI ::r-< ~ UI rt C. (D CU :3 formerly 'at prassnt :3 III ~. :J :J a. ••••••• n tl rt n :r :D '" O· ..
...... TON. .... ~ '" '.. 70
60
w
50
40
30
20
10 Wl - -x, A ...... ,._ .... .",...... /' B X' - ...... _ ...... ~ -"" -"""...... J::,. _ x__ - -A J...--_-J------l--1 _.---J-I---_--_-t------1< 1953-60 1961-68 1969-76 1977-84· 1985-90 YEARS Fig.3. Cotches af sea traut in the years 1953-1990. UW Vistula's estuary. W_ V1stula /whole/. T- Vistula Tczaw. Wl _ Vistula Wlaclawek. B- V1stula Bydgoszcz. /N1sn1e wolski 1987. Bartel 1976,1989. Bartel. Z1eliriski 1977.': . 1978.1979.19a~.1982.1984.1985a~~,1986a.b.19878.b.1989 •. 1991 and 83rt~1 - unpub11ehed .ater181s/. [ . ,. ..
•
-0
/ / / /,
c o o o o o ~ N ..
Fig.A. Stacking of Vistula and DrwQca with the sen traut sgolts 1n the years 1972-1991. W - Vistula - whola, 5 - ViGtula - estuary, D- Dr~~co. /aartel 1976.~989. Bartel. Zialinski 1977.1978.1979. 1981.1982,1984,1985a,b,1986a.b,1987a.b.1989,1991 end 8artel unpub11shed data/ .. f- 0 -l 0 00 c: o ::: t () L"'l (,n ~ .... -- o - ,C'\ - I - - - - ._. I - -~ I / I " lf) CO , , _/>
~ - - ""- ""- ;/ / / o < , CO ""- "' ./
- - -- ,
o o o ...., ~
Fig.5. C~tches of sea trout ond stocking ~ith the 3~oltc /rcarod from notur31 3pawning and smolts from roloo~cd ~lovin in tho years 1972-1991. 1 - ~ea traut catchest 2 - stocking with s~olts. /89rtol 1976.1989. 3artol. Zioli~ski 1~77, '1978.1.979',1981 ,1982.1984,19850 , b .1986,3 . b , ~ 987") .!J .1989 • 1991 3nd B3rtol unpub11shod dota, ~i~n1cwol~ki :987/. 1-0 ..JO QO .,;,.. I c o o o (J) o Ln· o o 0 Cf) "''1 C\l N .-\ Ln 0:: W< -- >- 0 - t-f N ,Cl - --- -
l(i ,CO "'-... e -- '-.. '-.. / / -' / / / ...... "'- "- ,/ /' j.g / / .-- ...- / <:: -- - -... -... -- -,'<----? \ .----
'" l!l '\ r-.... \/ , ,A' "'1 I I I
-1-.-L---!.---!....----!--..!..---L.-~-_L____!__,:,....:..__l..__~_ _4 :r.: o o Z o o I-- 0 t--l 1..'1 <. ~ ü
Fig .. G.. Cntchcr; of GOO trout 'in th!] yni:lr::; 1972-;199l Dnd stocking with s~olts with onc ycar shift ~pplied. /Conparc with Fig.5.1. 1 - sco traut cntches. 2 - stockina with s~oltc...... ~
" ,>
\ \ \ ~ c ! I #~:~; :y/)' \ \\1: , I' ,_
/ I / / ~0 . / , \ \ I ;' \I \ \ \ \ \ ,\ 1\ I . \
u Z o o f- 0 o Ln -< } ~ U Fig.7. C3tch~5 of 3e~ traut.in Vi3tula rivcr in tho V03ro 1972-1991. ','rr-'/i::>tul:) th(~ \':1'1010 riV~::H' :lnd tho '-l:;tui~)r'l, S - '/it.3tul;)'::; C$tu3r~/, T-TcZCY/. \'l-o/lloclo\\'ok. 3-3':,clg i)szcz. I/Bartol 1975,1989, 8~rtol, ZiDliri~ki 1977,1978,1979,1901, 1982.1984.1985a,b.1986a,b.1987a,b.19ß9.1S91 3nd Bortol unpublishcd dn:~. W16nicwolgki 1987/.