Burge, Richard

English

Aquatic Commons

State  of California - The Resources Agency 
Department of Fish and Game 
Marine Resources Region 
Long Beach, California 
CRUISE REPORT 73-KB-17 
ABALONE INVESTIGATIONS 
Prepared by Richard Burge 
Vessel:  R/V mLP BASS 
Dates: J u l y  18-26, 1973 
Loca l i t y :  San Clemente I s l a n d  
Objec t ives :  1. To t a g  p ink  and green  aba lones  f o r  l i f e  h i s t o r y  s t u d i e s  
and t o  i n s p e c t  new a r e a s  f o r  survey and r e l e a s e  of 
tagged abalone.  
2. To o b t a i n  d a t a  on abalone cond i t i on ,  behavior ,  pre- 
d a t i o n  and on environmental cond i t i ons .  
Procedure: Scuba d i v e r s  picked aba lones  i n  pre-se lec ted  s tudy  a r e a s .  
Care was taken t o  avoid unnecessary c u t t i n g .  Abalones were 
brought aboard t h e  v e s s e l ,  tagged through t h e  two a n t e r i o r  
r e s p i r a t o r y  por&s w i t h  s t a i n l e s s  s t e e l  t a g s ,  and measured 
f o r  l e n g t h  and width. The weight measurements were no t  
taken due t o  v e s s e l  motion. 
Tagged abalones were r e tu rned  t o  t h e i r  o r i g i n a l  r ee f  and 
p lan ted  on a f r e s h  abalone scar .where p o s s i b l e .  
Resu l t s  : A t o t a l  of 1,870 p ink  abalone was tagged, 999 a t  China Cove 
and 871 a t  Pyramid Head., B i o l o g i s t s  a l s o  tagged 7 7  green 
abalone and p l an ted  them j u s t  i n s i d e  Pyramid Head. 
Moderate bottom su rge  p reva i l ed  i n  t h e  s tudy  a r e a  throughout 
t h e  c r u i s e  prevent ing  our  occupying t h e  shal low a r e a s  
o r i g i n a l l y  des igna ted  f o r  green abalone t a g  s t u d i e s .  
Large b a t  r a y s ,  QZiobatis  caZifornica, and sheephead, 
PimeZometopon pulchrm, preyed heav i ly  on t h e  r e tu rned  
abalones.  They appeared t o  be  a t t r a c t e d  t o  hemocynin l o s t  
by aba lones  c u t  du r ing  cap tu re .  To a l l e v i a t e  t h i s  prohlem, 
w e  stopped r e t u r n i n g  c u t  i n d i v i d u a l s  t o  t h e  wa te r .  Bat r a y s  
were o f t e n  observed b i t i n g  a t  and crushing  aba lones  p l an ted  
on exposed s u r f a c e s .  Divers  f r e q u e n t l y  found f r e s h l y  broken 
s h e l l  on t h e  bottom and recovered t a g s  t h a t  were l o o s e  o r  
s t i l l  a t t ached  t o  a p i e c e  of s h e l l .  On two occas ions  b a t  
r a y s  took f u l l  bags of aba lones  from d i v e r s .  
Sheephead o f t e n  fol lowed d i v e r s  and were a b l e  t o  knock a 
weak o r  f r e s h l y  p l an ted  abalone from i t s  s c a r .  When t h i s  
occurred ,as  many a s  50 o r  more f i s h e s  f ed  on t h e  abalone.  
Although sheephead were t h e  dominant s p e c i e s ,  k e l p  b a s s ,  
ParaZabrax cZathratus, g a r i b a l d i ,  Hypsypops rubicunda, 
and s e n o r i t a ,  OxyjuZis caZifornica, o f t e n  p a r t i c i p a t e d .  
Ea r ly  i n  t h e  c r u i s e  w e  l o s t  about  20% of t h e  tagged abalone 
due t o  p reda t ion .  P reven t ive  measures reduced t h i s  l o s s  
cons iderably .  Fur ther  p recau t ions  a r e  t o  b e  t e s t e d  dur ing  
t h e  next  c r u i s e .  
Personnel  : Marco Mazarovich , Vessel Captain 
R. Burge, Biologis t- in-charge 
S. Schu l t z ,  B i o l o g i s t  
M. Odemar, B i o l o g i s t  
R. Hardy, B i o l o g i s t  
R. McAl l i s te r ,  B i o l o g i s t  
MRR-LB / 150 
8 - 7 - 7 3 1 ~ ~  


Cruise Report 73-KB-17: Abalone investigations

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Cruise Report 73-KB-17: Abalone investigations

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