CM_1962_Preliminary_report_Rosseland.pdf (247.5Kb)

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Tagging of Salmon Smolts in the Lone River, the Eira Hatoh8ry

911 the Lundeso-Icna Hatchery h1 lToTl'my.

Preliminary Report by Le1v Bosselcmd.

The Lone river near Bergen is one of the smallest salmon rivers in Norway, and It'li th a populationrcainly of small

f~rilse .

~)ince

1956

small numbers of sn:olts have been tagGed 1n the river. The srr:olts have been cau~;ht by electrical fishing

3~ar shortly before thEir seaward migretion - mDinly in April - and both 08rlin tags and Lea tags have been us-d. As shown in table I the percentages of recapture fron: these tCl{sc':;ings have been t~e highest eveh obtained in Norway.

In the LUl1desokna hatchery near Trondheim the sn:olt tasc;ing experiments started in

1957.

1:1 that year, and in the following tV'lO years dr. B0r je O::-n::-lin took pent :Ln the expe:rirrents, and taught us the technique which he had used in Sweden. He

also brought l,vith him !tOarlin tagsl1 made in Sweden. In the following years hoth Carlin tag,s and Lea tags 1:1.<::lve been used.

The smolts have been reared in ponds and troughs and usually the srr,)lt stage is reached in two years.

~~}1e srwlt reared in Lundesokna should be, as for as

I can see - compcnable to the smolt reared j.n Swe,len. The

tagc;ini:; teclmique used should also be nearly iclentical wtth the Swedish procedure.

But;, ["is seen i table 11, the percent'<::lse of rec3pture is :far lower than usually in Sweden t perh:JPs wtth exception of the

1961

t8~~ins.

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11.

The Eira Hatchery is situated some 50 kilometers from Molde. In this hatchery the srrolts also usually are two yecHs old.

The same kind of tags a the same taG~ing technique is used j_n Eira as mentioned before fo~~ the J-lunclesokna .exl'Jer1- ments.

As seen in table III the perc2ntagES of ::cec2:\pture are very low, especially for the first year of the experiment.

In all the experimerrts the majority of tagged salmon were rer;aptured after one winter in the sea.

None of the experiments indicclte that the, sll;olt rearing is economically sound. but thera is a re~arkable in- crease in the recapture percentage, both in tlle Lundesokna experiment, and in the Eira experiment.

]ltnally I will dravv your attention to the ren:arlcc!ble differences in sea and river recaptures in our sn::olt ta,~sing and cle.::m salrr.on tcl,S,sing exprc;riments. As seen fron: table IL. and table I:i:Jonly 6.4 - e.o per cent of the recaptures from reared smolts have been mgde in rivers, vvhile

92 - 93.6

per oent hgve been caught in the sea. From table IV '.vill be seen that of clean salmon a considerably 11i;zher IJGrCentage h~·,:J 'I)een recau8~l.t in

rivers. I have a feeling that the main reason for this diffe- rence (LaY be the fact that the stock of clean salmon has cl11ready been reduce d by the sea -fishtng when tag;lng be c~ins .

Oslo, October 1st

1962.

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-.L

Salmon smolts tagged in Loneelv, Norway. Wildfish. Re-Numb' Mean; Recaptured as adults

I

" I tag,;. lenght:l

1957 1958 1959 1960 19 61

1962!

Total Total

I

1 .. I . ged f in cm ';Numb. ),0'lght 0 Numb 0 Wght. Numb.

I

Wght. Numb .jWght 0 Numb 0 (,vght

.~Jumb.

VlTght

>!

Numb. IWght.

I

caught

%

if-~-~---T

!

!~~--I~----I-

-- - --I 50 13.7

1;

7. :.

I

71 9·11

: ~ f _ 1 _____ t___ _ 1___ _ ____ L-~~ __ i _~ _____ ~_

14

:-~--!

182 14.7!1 6 8.8 6 8~. 8-'

3~3

845 12.7li I 841 1251 81 291 31 ~--I~----I-;;fl~;--l

'''_c _ ~i "-_L _ ~ __ L ____ ~ __ L ~ ~_t ____ L ___ -.J_~_ ~ __ J _____ I

11.2

---,.----,---~-~'--·-··-·--~-'--~---,~---~-I---·~--,--.----~;.--~ '-,', -1 ~ • , I '" i', t I ' r 5 i '; t l f t ~ }, t

59

(i l " t ;

! (

!

I

i

I

JJ ~ _ ~ ~ ~ ~ { t ---if~~ d~---:~-· -----;---'----l---f-------T--

907 13.~\ \ '

I. I

85 12& 8 21 93 147 10.3

~ __ of ; ! ' , I I ~

995 13; 66 98! 661 9 8

.-L_ ______ t _ __ __ ___ _ __ J ________ J

6.6 950 3929

---,;-~ ----1---t ----,------,-- n I f I

" I'

t , I

i: !,;

! ~ ~ : t t t ~ '. t

. 7

9.1~

6 8.8! 84; 125: 8 291 88 135: 74' 119; 267 426

t t· ~ ~ . until

28

th September

1962. 12ee?{A.e'j.;[l ~/t /y~VVU I 'i b ~

<-A':?""

o-u

~£-~----/'I--f:-~'-;1

.sI

7 ~

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~ Yearl Numb tagged

Mean

i

lenghtj

Ji

Salmon Smolts tagged in the Lundesokna hatchery, Norway Recaptured as adults in cm

! 1958 1959 1960 1961 1962

Total t i I Numb. VJght Numb;~ VJght.1 Numb. Wght Numb .VJght.i Numb,. Wght Numb

I I .

! ~ \

Totall. Re- Wght., caught

. 9;

1 t -"---

-r --- -r- --

-~--r-

---

r

1957 2957 16,8 H 21! 47.-1 5

12

7.

1

I! 8.5 27 '83

1 .... t ; i ~ , t t i

1958 2353 11'J6 If ! 19 15 0 .3! 10 ~4.1 6 54.5; 2 ~18.1 37 187 1.6

~ :.' 1 t._ ____ _ 1 ____ .. _______ _ r----! ---~

1959 2095 ) I 2 4 2 4

0.1

19 6 0 11213 li,3 14 23,4; 4 22 18 45 1.5

f ~

19 6 1

6558 16,6 I 1197 64 8 197 64 8 3.0 19 62 7499

Total ;

22675 :

^_______

___ _ __ l _________ .. ______

.t_ .. ________ ... .. _ n

f1 t ~ ~ ~ (i ~ ~ f' Reported until

28

th September

1962

..f7 _ tf (J ?U-t:ev,",t.

rA/lrr

__ r;' ... ----

'. 4-"4 -"-""

_-"l/U~-'l-:f &, f../ '%

a -~ / --f...c4~ 7 i-/I (.P I(

281 967

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Salmon ^~moltstagged in the river Eira, Norway.

( c"l')lts ,.J.^C ' . ,_ fro"" ~.~L.~ t·'J.e - ~l'ra 1J.a.tc·'~PT'·y .,'J _ ... C __ ..l.\..J_ . ) \

]"tea.n

~-__ =---~, _~",~~"...~-.. ... _~. _~_~'~~_._~~ _ _ ' _ _ _ T=~"""i _ _ ~~ _ _ ' _

l ",,,- 1 :::\J ⁱ ^'1l... ' / '''~ I~j?... ^'. Tt) , t .8..·L '1'.0 l' .L '-' ,o.·l c.. i 0~ /' .-T' ,-... J

lengh. ^t:;

13 9' _{. "} _1: ⁵ 38. .1 ^{1 ?:} ^"7^{. .J ,}^{.~'

-

^{( ) Q}^C}⁵

1 2100 30 132. j 30 ^{() 2. ,}J

-i -~-.--;:-~

Reported until 28 . Septewber 1962. th

/Z~~flCt'f 8;-

/uc~

92,-

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--'--- /)/

Clean Salmon tagged at the Norwegian coast

1935 1961

Hille

'\ligan

H m

Q)

N

1957- 1959 I

-+

1940

"

~ '.

j :

2341:

j ~

I '

~ f

p, I

m o

en H H

(])'U

,.oil) 8tH ;:J ;:J

~~ p

123

¹

,

9

¹

Rong 1935-

^l

1936

ⁱ

174;:

^"

r!

85

Hel

VCBr 1936- ' 1940

r"

l\lnn

,

- - - - ' -!-

'l'itran

farva

BjorOYVCBr

1947- 1961 1935- 1940 1947- 1958 ,

lCJ51- 1956

Kvaloyham 1954-'

~----+----:

} t

615 ;1

1479 : 850 1879

^l'

857 1638 "

669' 352 435;, 252 1956 ;

--- !

^{- - - + -} ,-'----,~-'----

r,ortsund

"> 'i

vik

':oti::il

, }

,

;-

1937-1 1938 .

15 694 ;" 250

l

52.6 35.8 32.3' 22.2 48.8 ; 13.0 11.8

m Q)

I{f) 0, Cl5 Cl)

o.-e;

1J).p

H ^!>,

~

m:

.p"r! :S'

~ Hi

Q)'U 01

- () (l) ~:::; I

!' ~I H ~

co ;:J ~

tl; .p "r! ;

;

i

77.8! 0.0

_,

--L _ _ .-;-_

80.0

^!

3.5 81.0 6.3

0.0 0.0 3.5

,

·-~--i---

1.0

---~----~---~,

57.5 80.2

!

0.1

i

45.6 17.3 81.6 0.6 0.6

~ ~

- - - - ! - - - , - ' ----~-.. --

60.3 22.6 0.1 0·4

---~---,----;-,---

52.1 14.5' 85.5 I 0.0 0.0

57.9 81.0 0.0

73·3 0.0 36.0 22.8 61.6

.-~----~