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a u t h o r s

I n t e r n a t i o n a l C o u n c i l f o r t h e E x p l o r a t i o n o f t h e Sea

C.M. 1974/N:9

Marine Mammals Committee

I

WHALES AND SEALS MARKED I N THE NORTHEAST ATLANTIC I N 1974

I v a r C h r i s t e n s e n and T o r g e r g r i t s l a n d I n s t i t u t e of Marine R e s e a r c h P.box 2906, N-5011 Bergen-Nordnes

Norway

Whales

Two c h a r t e r e d s m a l l - w h a l e c a t c h e r s , "Ann B r i t a " and " B å r a g u t t " , were u s e d on a whale marking c r u i s e t o t h e B a r e n t s Sea and

S v a l b a r d from 1 0 J u l y t o 20 August 1974. The t r a c k s of t h e s h i p s and s i g h t e d and marked w h a l e s a r e p l o t t e d i n F i g . l . The d i s t a n c e between t h e s h i p s u s u a l l y was k e p t a t 2-4

n a u t i c a l m i l e s d u r i n g t h e c r u i s e , and t h e t o t a l d i s t a n c e steamed i n open s e a was a b o u t 3700 n. m i l e s . However, t h e w e a t h e r was u n f a v o u r a b l e w i t h f o g , wind and low v i s i b i l i t y d u r i n g t h e g r e a t e r p a r t o f t h e c r u i s e . T h e r e f o r e t h e

o b s e r v a t i o n s cannot. b e u s e d t o e s t i m a t e t h e d e n s i t y o f w h a l e s i n t h e s e a r c h e d a r e a .

S i g h t e d w h a l e s i n c l u d e 2 5 9 minke whales ( B a l a e n o p t e r a a c u t o - r o s t r a t a ) , 20 humpbacks (Megaptera n o v a e a n g l i a e ) , o n e f i n whale ( B a l a e n o p t e r a p h y s a l u s )

,

d o l p h i n s (Lagenorhynchus a l b i r o s t r i s ) and 17 comrnon p o r p o i s e s -

-

(Phocoena phocoena)

.

a r e n o t i n c l u d e d i n F i g . 1. A t o t a l o f 6 3 w h a l e s , 51 minke w h a l e s and 1 2 humpbacks were marked.

A n a d d i t i o n a l s e v e n minke w h a l e s were s i g h t e d and two o f t h e s e were marked n o r t h of S h e t l a n d on a c r u i s e t o t a g b a s k i n g s h a r k s ( C e t o r h i n u s maximus) i n t h e n o r t h e r n North Sea from 1 2 t o 30 May 1974. O b s e r v a t i o n s o f beaked w h a l e s

(Mesoplodon b i d e n s ) made d u r i n g t h i s c r u i s e , w i l l be r e p o r t e d e l s e w h e r e ( P e r Gynes, p e r s . comrn.).

The g e o g r a p h i c a l d i s t r i b u t i o n o f t h e e f f e c t i v e l y marked w h a l e s was a s f o l l o w s :

S o u t h e r n B a r e n t s Sea (Østbanken) E a s t e r n B a r e n t s Sea (Gåsbanken) Hopen I s l a n d

Bear I s l a n d

Bear I s l a n d - S p i t s b e r g e n

( S t o r f j o r d r e n n a ) West c o a s t of S p i t s b e r g e n North of S h e t l a n d

1 minke

1 5 " 7 humpbacks 2 0

"

T o t a l 53 minke 1 2 humpbacks

A l l w h a l e s were marked w i t h numbered ' D i s c o v e r y t t y p e marks ( M i t c h e l l , 1 9 7 0 ) . The 12-gauge s t r e a m e r mark was u s e d on humpbacks and t h e s m a l l e r . 4 1 0 - b o r e mark on minke w h a l e s .

Upon a d v i s e from A r c t i c B i o l o g i c a l S t a t i o n , F i s h e r i e s R e s e a r c h Board o f Canada, spun s t r i n g s t r e a m e r s had been a t t a c h e d

a l s o t o t h e .410-bore marks. I n s e v e r a l c a s e s t h e s t r e a m e r s h e l p e d t o d e c i d e whether t h e mark had h i t o r n o t .

The l a r g e r marks a l l b e a r t h e f o l l o w i n g e n g r a v e d l e g e n d :

"REWARD FOR RETURN TO DISCOVERY BRITISH MUSEUM (NAT. HISTORY) LONDON". The s m a l l marks a r e engraved w i t h e i t h e r "STATENS INSTITUTT FOR HVALFORSKNING. OSLO" o r "SENDES T I L HAVFORSKNING BERGEN"

.

A series o f o b s e r v a t i o n s made d u r i n g t h e whale marking c r u i s e s u g g e s t t h a t minke w h a l e s b r e a t h and a r e exposed t o t h e a i r f o r 3-4 s e c o n d s o n l y and t h a t d i v e s may l a s t f o r a n y p e r i o d between 1 2 s e c o n d s and 1 0 m i n u t e s o r mare when t h e y a r e f o l l o w e d ( n o t c h a s e d ) by s h i p s .

I n J u n e - J u l y 1974 a t o t a l o f 1 0 1 s u b a d u l t and a d u l t hooded s e a l s (Cystophora c r i s t a t a ) were tagged i n t h e E a s t Greenland p a c k - i c e i n t h e Denmark S t r a i t . The t a g g i n g s w e r e made

d u r i n g a n e x p e d i t i o n w i t h t h e c h a r t e r e d s e a l i n g v e s s e l ' F ~ r t u n a ~ ' t o c o l l e c t m a t e r i a l f o r a g e a n a l y s i s o f m o u l t i n g hoods. T h e s e a r e t h e f i r s t hooded s e a l s known t o h a v e b e e n t a g g e d i n t h e m o u l t i n g a r e a i n t h e Denmark S t r a i t .

I t i s b e l i e v e d t h a t hooded s e a l s b r e e d i n g i n b o t h t h e

Northwest and i n t h e N o r t h e a s t A t l a n t i c m e e t and mix i n t h e Denmark S t r a i t p a c k - i c e d u r i n g t h e m o u l t i n g s e a s o n ( S e r g e a n t , 1 9 7 4 ) . So £ a i o n l y two r e c a p t u r e s o f hoods t a g g e d a t

Newfoundland have i n d i c a t e d a movement from t h e Northwest A t l a n t i c t o w a r d s t h e Denmark S t r a i t : One f i v e - y e a r - o l d was r e c a p t u r e d n e a r Kap F a r v e l i n 1956 (Rasmussen and

Ø r i t s l a n d , 1 9 6 4 ) and a n o t h e r , a two-year-old, w a s r e c a p t u r e d i n t h e Angrnagssalik F i o r d c l o s e t o t h e Dennark S t r a i t

m o u l t i n g a r e a i n 1972 (Benjaminsen e t a l . , 1 9 7 3 ) . No

r e c a p t u r e h a s y e t been made i n t h e Denmark S t r a i t o f hooded s e a l s from t h e J a n Mayen a r e a . T h e r e f o r e any r e c o v e r y from t h e Denmark S t r a i t t a g g i n g s i n 1974 may g i v e s i g n i f i c a n t new i n f o r m a t i o n o n t h e movements o f hooded s e a l s i n t h e North A t l a n t i c .

A l l s e a l s were t a g g e d w i t h 'Jumbo Roto t a g s l ( D a l t o n S u p p l i e s L t d . , N e t t l e b e d , Henley-on-Thames, E n g l a n d ) , a t t a c h e d t o

the web on e i t h e r side o f t h e m i d d l e d i g i t o f t h e l e f t h i n d f l i p p e r . The f e m a l e p a r t o f e a c h t a g h a s a n i n d i v i d u a l

number i n t h e s e r i e s D0001-D0101 and t h e male p a r t b e a r s t h e l e g e n d "HAVFORSKNING BERGEN NORW".

I n t h e West I c e ( t h e J a n Mayen a r e a o f t h e G r e e n l a n d Sea) s e v e n h a r p s e a 1 p u p s a.nd t h r e e hooded s e a 1 pups were t a g y e d from t h e r e l i e f v e s s e l "Harmoni" d u r i n g t h e s e a l i n g s e a s o n from 28 March t o 29 A p r i l 1 9 7 4 . Jumbo R o t o t a g ' numbers w e r e C 4 0 2 - C 4 1 1 . A l s o o n e j u v e n i l e h a r p s e a 1 and f i v e p u p s w e r e t a g g e d f r o m t h e c e a l - e r " P o l a r u l v " i n t h e E a s t I c e ( t h e

p a c k - i c e i n t h e s o u t h e a s t e r n B a r e n t s S e a ) i n l a t e A p r i l l 9 7 4 w i t h 'Junibo R o t o t a g s s numbered m m D l 0 0 1 t o D1007,

The r e c a r t u r e i n t h e L o f o t e n a r e a of two o u t o f 1.5 minke w h a l e s marked i n t h e same a r e a i n 1964-1965 was r e p o r t e d by J o n c g å r d ( 1 9 6 7 ) . A f i n w h a l e marked o f f S o u t h e a s t G r e e n l a n d i n 1968 was r e c a p t u r e d a f t e r c e v e n d a y s , h a v i n g t r a v e l l e d a b o u t 280 n a u t i c a l m i l e s t o w a r d s I c e l a n d ( J o n s g å r d a n d C h r i s t e n s e n , 1 9 6 8 ) . No f u r t h e r r e c o v e r i e c a r e known t o u s f r o m p r e v i o u s Norwegian w h a l e m a r k i n g p r o g r a m s in t h e

N o r t h e a s t A t l a n t i c .

So f a r t h e r e c a p t u r e o f 1 0 s e a l c , a l l t a g g e d a s p u p s , h a v e b e e n r e p o r t e d i n 1974s T h r e e h a r p s e a l s t a g g e d o f f

Newfoundland-Labrador w e r e r e c a p t u r e d i n t h e sane a r e a a f t e r two, two and t h r e e y e a r s ; two more h a r p s e a l s f r o m Newfoundland w e r e r e c a p t u r e d a t West G r e e n l a n d a f t e r two a n d t h r e e y e a r s p f o u r hooded c e a l s t a g g e d i n t h e J a n Mayen a r e a w e r e r e c a p t u r e d i n t h e same g e n e r a l a r e a a f t e r f i v e , s i x , s i x a n d e i g h t y e a r s ; a n d o n e h a r p s e a l t a g g e d i n c o u t h e a s t e r n B a r e n t s S e a was

r e c a p t u r e d i n t h e same a r e a a f t e r two y e a r s .

One a n i m a l w h i c h had b e e n t a g g e d i n t h e J a n Mayen a r e a b o t h w i t h a Vumbo R o t o t a g ' a n d a n o l d f a c h i a n e d t a i l t a g (Rasmussen a n d Ø r i t s l a n d , 1 9 6 4 ) was r e c a p t u r e d w i t h t h e r o t s t a g o n l y . T h i s s i i g g e s t t h a t r o t s t a y s a r e t h e m o s t e f f e c t i v e . The r e c o v e r y o f a n e i g h t y e a r o l d r s t o t a g a l s o i s e n c o u r a g i n g , Eower jaws from f o u r r e c a p t u r e d s e a l s h a v e s u p p l i e d u s w i t h a d d k t i o n a l m a t e r i a l f o r a g e d e t e r m i n a t i o n o f knswn-age

a n i m a l s .

R e p o r t s of f u t u r e r e c o v e r i e s

I t i s proposed t o pay a r e w a r d ' o f 2 0 0 Norwegian k r o n e r s f o r t h e r e p o r t o f a r e c o v e r e d whale mark, Rewards of

N.kr. 30,- i s p r e s e n t l y b e i n g p a i d f o r r e c o v e r e d s e a 1 t a g s . An a d d i t i o n a l reward o f N.kr. 2 0 , - i s p a i d f o r e a c h s e a 1

t a g when t h e lower jaw o f t h e s e a 1 i s c o l l e c t e d and s e n t i n w i t h t h e t a g .

R e c a p t u r e s s h o u l d b e r e p o r t e d t o Sea Mamma1 S e c t i o n ,

I n s t i t u t e of Marine R e s e a r c h , P.box 2906,

N-5011 Bergen-Nordnes, Norway,

w i t h i n f o r m a t i o n on d a t e and l o c a t i o n o f t h e c a t c h and on

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t h e s e x and l e n g t h o f t h e a n i m a l .

Whale r e c a p t u r e s c o u l d a l s o b e r e p o r t e d t o Whale R e s e a r c h U n i t ,

I n s t i t u t e of Oceanographic S c i e n c e s , c / o B r i t i s h Museum ( N a t u r a l e is to ry)

,

Cromwell Road, London SW 7 5 BD, England.

R e f e r e n c e s

Benjaminsen, T . , B e r q f l Ø d t , B . , F r p l a n d , A . , Huse, P . , Ø r i t s l a n d , T . , and ~ S s c h e , A . , 1973. S e l u n d e r s Ø k e l . s e r i

d e t n o r d l i g e A t l a n t e r h a v i 1 9 7 2 iseal i n v e s t i g a t i o n s i n t h e N o r t h A t l a n t i c i n 1 9 7 3 . F i s k e t s Gang, 5 9 : 2 2 2 - 2 2 9 .

J o n s g å r d , A . , 1 9 6 7 . The Norwegian modern w h a l i n g f o r s m a l l c e t a c e a n s : A s u r v e y o f b i o l o g i c a l

i n v e s t i g a t i o n s . Coun. Meet. i n t . Coun.

E x p l o r . S e a . 1967 ( N : 2 ) : l - 1 4 .

J o n s g å r d , A . a n d C h r i s t e n s e n . I . . 1 9 6 8 . ^A p r e l i m i n a r y r e p o r t o n t h e 'Haroybuen" c r u i s e i n 1 9 6 8 . Norsk H v a l f a n g s t t i d . , 57:174-175.

M i t c h e l l , E . . 1 9 7 0 . R e q u e s t f o r i n f o r m a t i o n o n t a g g e d w h a l e s i n t h e N o r t h A t l a n t i c . ^{J .} Mammal.. 51:

Rasmussen, B. a n d Ø r i t s l a n d , T . 1 9 6 4 . Norwegian t a g g i n g o f h a r p s e a l s a n d hooded s e a l s i n N o r t h A t l a n t i c w a t e r s . F i s k D i r . S k r . S e r . HavUnders. 1 3 ( 7 ) :43-55.

S e r g e a n t . D.E., 1 9 7 4 . ^A r e d i s c o v e r e d w h e l p i n g p o p u l a t i o n o f hooded s e a l s C y s t o p h o r a c r i s t a t a E r x l e b e n a n d i t s p o s s i b l e r e l a t i o n s h i p t o o t h e r p o p u l a t i o n s . I n t . Comrnn NW. A t l a n t . F i s h . , ser. ^{N O .} 3 3 6 4 : l - 1 3 . m i m e o g

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Figure 1. Cruise tracks and observed and marked whales during the whale marking cruise with "Ann Brita" and"~åragutt"

10 July '- 20 August 1974. Full lines represent tracks by both ships together, broken lines represent the tracks of one ship alone. 1) 5 minke whales marked, 2) 1 minke whale marked,

3) 5 humpbacks marked, 4) 1 humpback marked, 5) 25 minke whales sighted, 6) 5 minke whales sighted, 7) 1 minke whale observed.