Methods and materials used to tag and recapture jack mackerel, Trachurus symmetricus, off the coast of southern California and Baja California, Mexico, are described.  Tagging, recapture, and movement data resulting from this program are reported.  Analysis of this preliminary data indicates a seasonal inshore-offshore movement pattern for this species within the range of the California fishery.  (9pp.

Tasto, Robert  N.

Aquatic Commons

A STATUS REPORT ON THE 
JACK MACKEREL TAGGING PROGRAM - 1/ 
Robert N .  Tas to  - 21 
ABSTRACT 
Methods and m a t e r i a l s  used t o  t a g  and r ecap tu re  jack mackerel ,  
Trachurms symt l . i cus ,  o f f  t h e  c o a s t  of southern  C a l i f o r n i a  and 
Baja C a l i f o r n i a ,  Mexico, a r e  descr ibed .  Tagging, r e c a p t u r e ,  and 
movement d a t a  r e s u l t i n g  from t h i s  program a r e  repor ted .  Analysis  
. of t h i s  pre l iminary  d a t a  i n d i c a t e s  a  s easona l  inshore-offshore 
movement p a t t e r n  f o r  t h i s  s p e c i e s  w i t h i n  t h e  range of  t h e  Cal i-  
f o r n i a  f i s h e r y  . 
11 Marine Resources Adminis t ra t ive  Report No. 8, 
- 
August 1973 
2/ Marine Resources Region, Long Beach 
-
A STATUS REPORT ON THE JACK MACKEREL TAGGING PROGRAM 
INTRODUCTION 
The jack  mackerel, Trachumrs s y m t Y i c u s ,  r e sou rce  o f f  t h e  west  
c o a s t  of North America is  known t o  b e  l a r g e  and widely d i s t r i b u t e d .  The 
spawning biomass i s  es t imated  t o  be 2 .1  t o  4.8 m i l l i o n  tons  based upon 
abundance of jack  mackerel eggs c o l l e c t e d  a t  s ea .  Adults  a r e  d i s t r i b u t e d  
from Cape San ~ u c a s  t o  t h e  Gulf of  Alaska, and range hundreds of miles 
o f f  shore .  
The C a l i f o r n i a  f i s h e r y  is  ope ra t ing  on t h e  f r i n g e  of t h i s  l a r g e  
popula t ion .  Landings . in  C a l i f o r n i a  s i n c e  1947 have f l u c t u a t e d  from a h igh  
of 73,000 tons  i n  1952 t o  8,700 tons  i n  1954. P a r t  o f  t h i s  f l u c t u a t i o n  
is due t o  vary ing  amounts of f i s h i n g  e f f o r t  d i r e c t e d  towards o t h e r  s p e c i e s ,  
and t o  r educ t ion  i n  s i z e  of  t he  f l e e t  over  t h e  yea r s  ; however, some v a r i -  
a b i l i t y  i n  landings  i s  due t o  d i f f e r e n c e s  i n  a v a i l a b i l i t y  of jack mackerel 
from y e a r  t o  yea r .  
. 
The reasons f o r  t hese  d i f f e r e n c e s  i n  a v a i l a b i l i t y  a r e  poor ly  understood. 
The of f shore  spawning popula t ion  seems t o  be  r e l a t i v e l y  s t a b l e ,  ht noth ing  
id known of  t h e  r e l a t i o n s h i p  between t h i s  o f f sho re  popu la t ion  and those  f i s h  
w i t h i n  range o f  t h e  C a l i f o r n i a  f i s h e r y .  The purse  s e i n e  f l e e t  seldom t akes  
jack mackerel o l d e r  than  6 yea r s  of  age ,  though 20 t o  30 y e a r  o l d  f i s h  t u r n  
up i n  t h e  s p o r t  ca t ch .  Most ca t ches  c o n s i s t  of f i s h  3 y e a r s  o ld  o r  younger. 
. Because knowledge of jack mackerel migratory behavior  i s  s o  meager 
many ques t ions  remain unanswered. Is t h e  jack mackerel resource  made up 
of  one l a r g e  in t e rb reed ing  popula t ion  o r  is i t  composed of a number of 
d i s c r e e t  subpopulat ions? W i l l  s t o c k s  f i s h e d  heav i ly  i n  one a r e a  b e  re- 
placed by f i s h  moving i n  from o t h e r  a r e a s ?  The i n i t i a t i o n  of a compre- 
hensive tagging  program by t h e  Department of F ish  and Game,  w i t h  funds 
supp l i ed  by t h e  Marine Research Committee, has  been t h e  f i r s t  s t e p  i n  
ga in ing  a  b e t t e r  understanding o f  j ack mackerel behavior ,  movements, and 
r a c i a l  s t r u c t u r e .  This  program w a s  i n s t i t u t e d  s o  t h a t  t h e  f i s h e r y  may 
develop t o  i ts  f u l l  p o t e n t i a l  under sound management. 
METHODS 
Tagging 
The tagging  program was i n i t i a t e d  J u l y  1, 1971. Pre l iminary  r e sea rch  
i n d i c a t e d  t h a t  t h e  Floy anchor t a g  (Del l ,  1968) had q u a l i t i e s  t h a t  made it 
q u i t e  s u i t a b l e  f o r  use on j ack  mackerel.  The t a g  could be  app l i ed  qu ick ly  
and i n  l a r g e  numbers by means of a  c a r t r i d g e  f ed  tagging  gun. Tes t ing  
by C a r l i n e  (1972) h a d ' i n d i c a t e d  t h a t  tagging  m o r t a l i t y  and shedding 
were minimal on f i s h  s i m i l a r  i n  s i z e  t o  t h e  jack  mackerel. The e x t e r n a l  
v i n y l  s h a f t  of t h e  t a g  had been demonstrated t o  b e  long  enough ( 3  inches)  
t o  be  e a s i l y  seen  by cannery personnel  o r  fishermen hand l ing  t h e  f i s h  
i n d i v i d u a l l y  . 
Experiments were conducted 'a t  Marineland of t h e  P a c i f i c ,  Undersea 
. 
Gardens i n  Marina d e l  Rey, and aboard t h e  R/V ALASKA t o  e s t i m a t e  n e t t i n g ,  
handl ing,  and tagging  m o r t a l i t y  r a t e s  and t o  f i n d  methods f o r  reducing 
t h i s  m o r t a l i t y .  Resu l t s  of t hese  experiments i n d i c a t e d  t h a t  n e t t i n g  and 
handl ing  m o r t a l i t y  were more s i g n i f i c a n t  than tagging  m o r t a l i t y .  Jack  
mackerel t h a t  were n e t t e d  and handled many times, r e s u l t i n g  i n  heavy 
s c a l e  and s l i m e  l o s s ,  s u f f e r e d  m o r t a l i t y  r a t e s  as h igh  a s  90% fol lowing 
apparent  b a c t e r i a l  invas ion .  When n e t t i n g  ope ra t ions  were k e p t  t o  an 
abso lu t e  minimum and water  soaked c o t t o n  gloves were used t o  handle t h e  
f i s h ,  m o r t a l i t y  r a t e s  dropped below 20%. 
Another form o f  m o r t a l i t y ,  though n o t  very  measureable,  was t h a t  
due t o  t h e  accumulation of  p reda to r s ,  p a r t i c u l a r l y  t h e  C a l i f o r n i a  s e a  
l i o n ,  ZaZophus caZifomianus, and t h e  b l u e  sha rk ,  Prionace gZauca, 
around the  tagging opera t ion .  It was n o t  uncomon, when working o f f  
commercial f i s h i n g  boa t s  a t  n i g h t ,  t o  encounter  f i v e  or  s i x  s e a  l i o n s  
while  r e l e a s i n g  tagged f i s h .  .Limitat ions on ope ra t ion  time aboard t h e s e  
v e s s e l s  makes such m o r t a l i t y  unavoidable. 
The smal l  wound c rea ted  by i n s e r t i n g  t h e  t a g  does n o t  appear t o  cause 
any g r e a t  harm t o  the  f i s h .  Examination of recaptured f i s h  wi th  tags  
s t i l l  at tached'  revealed t h a t  i n  t h e  g rea t  maj o r i t y  of cases s u f f i c i e n t  
sca r  t i s s u e  had formed around the  t a g  t o  p r o h i b i t  t a g  v i b r a t i o n  from in-  
c reas ing  the  s i z e  of the  wound. No attachment of t i s s u e  t o  any por t ion  
of t h e  t a g  was eve r  noted,  n o t  even on f i s h  t h a t  had been a t  l i b e r t y  f o r  
n e a r l y  1 year .  This  observat ion  i n d i c a t e s  t h e  wound remains a poss ib le  
s i t e  f o r  b a c t e r i a l  o r  p a r a s i t i c  invasion.  A smal l  number of t ags  t h a t  
had been out  f o r  3 months o r  more had considerable a l g a l  growth on t h e  
exposed p o r t i o n  of t h e  t a g ;  however, t h i s  a d d i t i o n a l  m a t e r i a l  does no t  
seem t o  adversely a f f e c t  t a g  r e t e n t i o n  nor inc rease  t h e  diameter of  t h e  
' i n s e r t i o n  s i t e .  
Of t h e  13,067 jack  mackerel tagged during t h e  f i r s t  2 years  of t h e  
program, approximately 40% were re leased  from commercial purse  s e i n e r s ,  
20% from l o c a l  b a i t  r ece ive r s  suppl ied  by lampara b o a t s ,  and 40% from 
s p o r t f i s h i n g  v e s s e l s  o r  Department research  vesse l s .  The f i s h  tagged 
aboard t h e  l a t t e r  two groups of v e s s e l s  were captured by hook and l i n e .  
Aboard commercial purse  s e i n e r s  a 23 f t .  X 2% f t ,  X 3 f t ,  plywood 
rece ive r  was u t i l i z e d  t o  r e t a i n  jack  mackerel during tagging opera t ions .  
The r ece ive r  was suppl ied  with continuous water  flow from t h e  v e s s e l ' s  
pumps, and was as  f a r  removed from t h e  f i s h i n g  opera t ion  a s  poss ib le .  
A s  many as  500 jack  mackerel could be  b r a i l e d  i n t o  t h i s  r ece ive r  from 
. 
t h e  v e s s e l ' s  n e t s  a f t e r  t h e  n e t  had been pursed and drawn c l o s e .  F i s h  
were withdrawn from t h e  r e c e i v e r ,  tagged,  and r e l e a s e d  dur ing  t h e  1 t o  
2 hours  t h e  fishermen r equ i r ed  t o  t r a n s f e r  t h e i r  ca tch  from t h e  n e t  t o  
the ho ld  and then  r e s t a c k  t h e  n e t .  
Tagging o p e r a t i o n s  from b a i t  r e c e i v e r s  r equ i r ed  l e s s  p repa ra t ion .  
The a v a i l a b l e  j ack  mackerel were crowded i n  t h e  r e c e i v e r ,  scooped i n t o  
buckets ,  tagged,  and r e l eased .  The lampara b a i t  f ishermen,  who supp l i ed  
t h e s e  f i s h ,  and t h e  commercial fishermen from t h e  p rev ious ly  mentioned 
purse  s e i n e  v e s s e l s  were f i n a n c i a l l y  compensated f o r  a l l  f i s h  provided. 
F i s h  procured by hook and l i n e  were e i t h e r  immediately tagged and 
r e l e a s e d ,  o r  r e t a i n e d  i n  a b a i t  t ank  t o  t a g  and r e l e a s e  a t  a l a t e r  t ime. 
Hook and l i n e  c o l l e c t i o n  avoids n e t  ab ra s ion  b u t  has  a major disadvantage 
i n  t h a t  t h e  s o f t  mouth p a r t s  of t h e  jack  mackerel a r e  e a s i l y  t o r n  dur ing  
removal of t h e  hook. 
Returns 
Tag r ecove r i e s  come p r i m a r i l y  from cannery personnel ,  a l though a few 
I 
. have been r e tu rned  by sportf ishermen.  Cannery workers handle  each jack  
mackerel t h a t  i s  be ing  packed f o r  human consumption. Consequently,  n e a r l y  
one-half o f  t h e  j ack  mackerel landed s i n c e  t h e  i n c e p t i o n  of t h i s  program 
have been handled i n d i v i d u a l l y .  The remaining tonnage of jack mackerel,  
from which we have rece ived  no t a g  r e t u r n s ,  is  converted i n t o  p e t  food. 
An experiment is  p r e s e n t l y  underway t o  determine t h e  percentage of  tagged 
f i s h  r e tu rned  t o  t h e  Department from those  t h a t  e n t e r  t h e  cannery f o r  
packing. Pre l iminary ,  b u t  inconclus ive  d a t a ,  i n d i c a t e  a 60% r e t u r n .  When 
a t a g  i s  recovered i t  must be  t r a c e d  through in t e rv i ews  t o  t h e  v e s s e l  which 
caught t he  f i s h  i n  o r d e r  t o  determine t h e  l o c a t i o n  of  r ecap tu re .  To induce 
cannery workers and spor t f i shermen t o  r e t u r n  t a g s  o r  tagge-d jack  mackerel,  
p o s t e r s  o f f e r i n g  a $1.00 reward were p laced  i n  t h e  v i c i n i t y  of a l l  
canner ies  and s p o r t f i s h  l and ings  throughout southern  C a l i f o r n i a  and 
Baj a C a l i f o r n i a ,  Mexico, 
RESULTS 
Tagging 
A t o t a l  o f  13,067 tagged jack mackerel had been r e l eased  by J u l y  1, 
1973 (Table 1 ) .  Genera l ly ,  those  r e l e a s e d  a t  Cortes  Bank and San Clemente 
I s l a n d  were tagged from commercial pu r se  s e i n e  v e s s e l s  and those  tagged 
and r e l e a s e d  i n  San Diego Bay and San ta  Monica Bay were supp l i ed  by lampara 
b o a t  b a i t  f ishermen. A t  t h e  remaining l o c a t i o n s  t h e  most f r equen t ly  used 
method of  procurement-was hook and l i n e .  
. . 
TABLE 1 .  Locations of tag releases and returns. * 
Number Number of 
Location Tagged Returns 
Ven tura 3 - 
Santa Cruz Island 
Santa Monica Bay 
Horseshoe Kelp 70 3 
Santa Barbara Island 5 7 
Santa Catalina Island 
San Clemente Island 
Cortes or Tanner Bank 
Bevport Beach 
Dana Point 
La Jo l la  . 
San Diego Bay 
Baja California 
Questionable 
TOTALS 13067 135 
Returns 
There h a s  been a t a g  r e t u r n  r a t e  of over  1% f o r  the  f i r s t  2 yea r s  of 
the program. Considering the  f a c t  t h a t  l e s s  than  50% of t h e  f i s h  landed 
by commercial b o a t s  a r e  handled i n d i v i d u a l l y ,  we f e e l  t h a t  t h i s  f i g u r e  
r e p r e s e n t s  a reasonable  r e t u r n .  The f i g u r e  is  somewhat i n f l a t e d  s i n c e  
fol lowing a tagging  ope ra t ion  aboard a purse  s e i n e r  t h e r e  i s  usua l ly  a 
s u b s t a n t i v e  r e t u r n  of t a g s  t h a t  have been a t  l i b e r t y  a week o r  l e s s .  This 
s i t u a t i o n  r e s u l t s  from an accumulation o f  f i s h i n g  b o a t s  i n  t h e  same a r e a  
f o r  as long as t h e  good weather  ho lds  ou t  and t h e  f i s h  schools  remain. 
About 17% of t h e  t a g  r e t u r n s  have f a l l e n  i n t o  t h i s  category.  
The average tagged f i s h  was a t  l i b e r t y  2 months be fo re  r ecap tu re  
and t h e  extremes range from 1 day (minimum) t o  373 days (maximum). A 
t o t a l  o f  t h r e e  f i s h  has been recaptured  a f t e r  be ing  a t  l i b e r t y  f o r  approx- 
imate ly  1 y e a r .  
Movement 
Recaptures i n d i c a t e  a cons iderable  amount of movement w i t h i n  t h e  
f i s h e r y  (F igure  1 ) .  Those f i s h  , t h a t  have demonstrated s u b s t a n t i a l  
F igure  1. Movements of jack mackerel a s  i n d i c a t e d  by t a g  r ecove r i e s .  
movement (Table 2) averaged 71 days a t  l i b e r t y .  The g r e a t e s t  movement 
no ted  was from San Diego Bay t o  San ta  Monica Bay over  a 212 day per iod .  
The number of ques t ionab le  r ecap tu re s  (Table 1 )  r e s u l t s  from an occas iona l  
i n a b i l i t y  t o  p i n p o i n t  t h e  l o c a t i o n  of r ecap tu re .  I f  a number of  b o a t s  
from d i f f e r e n t  f i s h i n g  grounds unload a t  about t h e  same t i m e ,  t h e  r ecap tu re  
l o c a t i o n  is  i n  doubt. 
, . ,+- 
TABLE 2. Substant ia l  uavement of tagged jack mackerel. 
Recapture Number Days a t  
Date of returns l i b e r t y  Point  of re lease  Point  of recapture 
Nov.16,1971 3 19,28,30 Catalina Island Horseshoe Kelp 
Nov. 22, 1971 1 37 Catalina Island Horseshoe Kelp 
k c .  10, 1971 1 .  43 Catalina Island Horseshoe Kelp 
Dec. 16, 1971 1 63 Eorseshoe Kelp . Catalina Island 
Jan. 3, 1972 1 67 Catalina Island San Clemente Island 
Jan. 10, 1972 1 74 Catalina Is land San Clemente Is land 
Jan. 21, 1972 7 97,85,90, Catalina Island Santa Barbara Island 
91,92,95,95 
Feb. 8, 1972 
Ju ly  10, 1972 
Aug. 6, 1972 
Aug. 8, 1972 
Aug. 10, 1972 
Aug. 20, 1972 
Sept. 14, 1972 
Sept. 16, 1972 
Catalina Is land 
San Clemente Island 
San Clemente Is land 
San Clemente Is land 
San Clemente Island 
San Clemente Island 
San Clemente Island 
San Clemente Is land 
Horseshoe Kelp 
Cortes Bank 
Tanner Bank 
Cortes Bank 
Cortes Bank 
Cortes Bank 
Cortes Bank 
Cortes Bank 
Oct. 9, 1972 1 102 San Clemente Island Catalina Island 
Dec. 9, 1972 1 66 San Diego Bay Newport Beach 
Jan. 9, 1973 1 184 Cortes Bank Catalina Is land 
Hay 6, 1973 1 212 San Diego Bay Santa Monica Bay 
CONCLUS IONS 
Although a l l  of t h e s e  d a t a  a r e  pre l iminary  and incomplete ,  they  seem 
t o  sugges t  a s easona l  inshore-of f sho re  movement p a t t e r n .  F ish  tagged a t  
Cortes  Bank dur ing  t h e  summer have been recaptured  t h e r e  approximately a 
y e a r  l a t e r  and a s i n g l e  f i s h  was recovered a f t e r  184 days l i b e r t y  a t  
C a t a l i n a  I s l a n d .  F ish  tagged a t  C a t a l i n a  I s l a n d  i n  t h e  f a l l  moved t o  
I 
Santa  Barbara I s l a n d  and San Clemente I s l a n d  during the  w i n t e r ,  and a 
s i n g l e  f i s h  tagged a t  C a t a l i n a  I s l a n d  t h a t  same f a l l  w a s  recaptured  
n e a r l y  1 y e a r  l a t e r  back at C a t a l i n a  I s l a n d .  A number of f i s h  tagged 
a t  San Clemente I s l a n d  dur ing  t h e  f i r s t  p a r t  of summer have been re- 
covered from Cor tes  Bank dur ing  the  la t ter  p a r t  o f  t h e  summer and one of 
t h e i r  number was r e tu rned  from C a t a l i n a  I s l a n d  i n  t he  f a l l .  Combine t h e s e  
movements w i t h  commercial j ack mackerel landings  s i n c e  1965 , which show 
an increas 'e  i n  a v a i l a b i l i t y  of jack mackerel o f f sho re  a t  Cor tes  Bank dur ing  
the  s p r i n g  and summer months and in shore  a t  C a t a l i n a  I s l a n d ,  San ta  Barbara 
I s l a n d ,  and Horseshoe Kelp dur ing  t h e  f a l l  and w i n t e r  months, and a p a t t e r n  
begins  t o  emerge. 
REFERENCES 
Car l ine ,  R. F . ,  and 0. M. Brynildson. 1972. E f f e c t s  of t h e  Floy anchor 
, 
t a g  on t h e  growth and s u r v i v a l  of brook t r o u t  (SaZveZinus fontinazis) . 
J. F i sh .  Res. Bd. Canada 29 (4) :458-460. 
D e l l ,  M. B .  1968. A new f i s h  t a g  and r a p i d ,  car t r idge- fed  a p p l i c a t o r .  
Trans. Amer. F i sh .  Soc. 97(1):57-59. 


A status report on the Jack Mackerel tagging program

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A status report on the Jack Mackerel tagging program

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