This not to be cited wi or reference to

International Council for

the Exploration of the Sea

CoM 1978/M 24

Anadromous and Catadromous Fish Committee

Refe: Mariculture Cttee

AGGRESSION AND GROWTH OF DIFFERENT POPULATIONS OF ATLANTIC SALMON PARR

By

l\iarianne Holm x) and Anders Ferno xx)

A B S T R A C T

In order to study aggression and growth of salmon parr of different populations and the possible effect of fin-clipping on these trai~s hatch.ery

1 Swedish) were

each Three

orig·inating from three populations ( 2 Norwegian, stocked in three aquaria with 90 unmarked fish in

a were stocked with a mixed group of 30 each of the These fish were fin-clipped (adipose or pelvic fins) order to enable identification of group~ Observation time was 1 ium, altogether 28 days of observation were made,, ~rcyta1 tal time was 8 weeks- Significant differences in sti beh as well as in growth (p<O,ool) was found bebi'leen the populations An effect of fin-clipping could also be

tected in th s t

dominancy for

At least one fish per aquarium established f the time. Most of the dominants in the mixed

~:1ro ca~me from the same poptllation.

x) Institute of Marine Research, Directorate of Fisheries, N-5011 Berge~ Norway .

. )cK) D t:trten F' isheries Bi logy, University of Bergen, N~ 01.1

IN•rRODUCTION

Salmon a. re

l958)o A rel

al under natural conditions (KALLEBERG

between aggression and growth under high

densi tires has by BROWN (1946 a b) and REFSTIE and KITTELSEN (197 )o under re

et al 1976), salmon parr showed seve kinds of sive , and dominant individuals with te territorial defence!were establishedoAggression and growth of small and large fish were estimated in different

ities

In

rent

cl

of

ri.v

l!S

paper, growth and aggressive behaviour of diffe-

of almon parr have been studied us fin-

as a marking techniqueo Behavioural dif s

populations 6ould be relevant to selection experiments

(NAEVDAL et al 1976) and fin-clipping as a method

fish has used in several studies, possibly

tematic errors

Mi~TERI.l-\L AND MErrHODS

in the

fi

iver

E:tne=river

:fi

.J

were second generation of

different rivers, i e Lonevag­

stern Norway and Skellefte­

river is a

big salmon

area in Gulf of

'rhe Skellefte­

a where

The Norwegian fish

a The of the fish

indivi growth ra·te

j of 1977 ld

iment also

ld start

1 ib wi a

1'he

- 3 -

was 10 + 1.0°C and the od was 12 hours s

fluores

was s

unre

of sh

30 a .. mo

lights

d with 90

had

00

sb. (1

"rhe source of illumination was lOO W white aced on top of the aquariam .Each aquarium

v a density which during earlier

250 g

~ve

not too

conditionso At the start of

were 50 99 mm long and the total weight

for an aquarium with solely

was 200 g,

fish were fin=clipped in order to enable identification of populations

irJ.

e

were s

l

to avoid

i.n=cl

in t.he

2.

The fin=cl was rotated

tematical error and to detect possible

on behaviour growths The populations

as Pig0 1

uariurn no,

4 5 6 ~"'==~~

90 90 90 30 s f u 30 E, U

30 S, A

30 L, P

u u u 30 L, A

L E s 30 E, p

of the~ fi.sh

(J

p

J" 00 and on t.he

~Fbe order

one

ilmrtt::di ate

4

2

c t.

4 -

ter transcr f.i

were attacked by b al gill disease a 5 weeks;

which caused some and possibly affected behaviour

20 - 24

vile re to satiation by hand at approximately 9 00

ods

~r.he

chargeu

FERN{Z} et al o

all ea

fi

1

.00 0 p.m every during observation

when not observed at 8.00 aom., 11.30 aomm and

on Sundayso

recorded aggressive behaviour were: Attack,

and these terms were used as scribed in

(1976) ~ In this paperu , only the sum of

s taken into account. The s of the

of the dominant fish were

(cf SOKAL and ROHLF 1 69 and

'HESULTS

dominant fish in

si

i. 0

fend­

day

0 Table 1

a

rencE~s

30

s

an

pe.L

popu

1

f:i

= 5 =

gToups of a 1 and di

; { )

Etne­river

1381

ficant (p < 0 01, Wi

Etne and Skelle

llefte~

r r

1 5 767

rs

and Lonevag and

ile it is nearly significant Etne and

(p- 0 075)~

ive in the mixed ations (i.ee

and 6 is presented in tab Subj et to

variance the da·ta (number aggressive ons

i revealed significant differences

actions made f different

an and

t of cl on tic

tions rnade different and

f tot.al arnount in each lllll

No in Dominants not included

ati

N %

8

( ) 8 515

6

rent

et of I , t i. lJet\ileen

N U1ttl:1 e :r

and cent of total amount in each

aquar urn. Auarium Nom in

Mark~

Ux1mark.ed

fin

fin

N total

sum of

( 4 20

were change

d

1

Skelleft:e N

n n % % total

6 0 0 187 29 9 ( 5) ') ..,) 3 39 ( 4) 663

270 34 (4) 16 8oQ ( 6) 713

20 5o9 ( 4) 103 24e0 ( 6) 158 25 3 ( 5) 465

7 560 34

tribution of aggression (Tables 2 and 1s the

sive actions during the whole ervation time

It must be

tween the different.

q du.r attack of cacte

with a.ntibi

c1i ffe:rences

we

s

the

there

11

which

servers.

sh in the

an

lay=

of

s

7 =

le 1The u liz :[

(8. .w.e.eks ) . o

Illlean g

ne.

1 ± 6 5 ±

2 Et ne u l ± lull 3o3 ±

3 u ± 1 6 5~0 ±

0 ± 1 16 4 0 ±

A 2 7 ± Oo96 4" 7 ±

p ± 1 13 4o2 ±

1 57 ±~

± 1.63 4 ±

p 7 ± 1.,. 0 4 8 ±

n .2 9 _t l 92 7 J:

6 * 7 ± 1. 39 4 7 ±

p :±. 1 ,, 43 5.0 ±

D -

I?

SCUSS ON

tb.

'Tl.i.

y

c;r l j c J,

I!

nu.

1 I 1 I 1

J: Sd

"6

2 14

2 0

2 0

le93

2"48,.

0 0

3

rJ J

a06

·t

i

I) HI

c growth

fac·tor rate

5 7

2.,5 5e64

1 6 7a25

6.,58

2 1 6 .. 93

6 48

7"45

1 7 5 77

7 19

6 06

2 0 6 93

8 24

1] and

nan

parr.

mot

.to ups

h

ngford

could

'Thi

c~ti vi

group

ting

' 8 =

roup parr 1

1 sion was rel ly

.J'::

.L

with cut pelvi

a) Fisb. ·itli

b)

1

c) Rentovc1l f

In th

1 7

on aggress to be fish

les

mi ult

have a weaker display of

in pelvic fins are used in

behaviour

ve les swiooning and

c fins might it di

lose to the bottom, which seems to

r it is not pos ible, pe due to

, to ve si ficant statistics

pa:cr t.o near in

uqge ts 1

demon~

71, al

cone

wit.h

9 -

R E F E R E N C E

Brown, MaE 1946 . The of brown trout (Salmo trutta

Linn ~ )

1946b~

I

I Factors nfluencing the growth of trout

l.Biol. 22 118-129.

.c L

11,

of brovvn trout__ ( almo trutta Linn 0)

old trout at a constant

1. 2 130-1440

" A.,, HOL.ft1 17 M,. and ROA.LD,S 1976 Aggression and growth of

Atlantic almon in different stocking densities.

ICES C~Ma 197 37:1- 13

HUNTINGFORD,PoAa 1 76 relations between anti- ator be-

tJJEV[l}\L G

',i

ha. vi our aggression among fi in the three-

2.4 45 Oo

V

)il

r;, c. H .1,

f( I

Anim Behav

lions in a stream tank of territoriality

on in juvenile aJmon and trout (Salrno

cJi

Yl

T

I Ll

['J .. ; I

;0 Do 1 7 • ti almon.

shvv. Hes

iments with ICES 975

a 1 maturi

11 L ib families

iences ..

.776 PP~