California's 1972 ocean shrimp landings totaled 2,488,683 pounds, a decrease of 585,857 pounds from the 1971 season when 3,074,540 pounds were landed. The decrease resulted primarily from the failure of the vessels to reach the quotas in Areas A, B-1 and B-2.  (18pp.

Dahlstrom, Walter A.

Nelson, Nancy E.

English

Statewide Pacific ocean shrimp landings for 1973 are totaled

and compared with the 1972 season. Landings by area are

described in relation to poundage by month, catch per unit

effort and fishing area. Sampling results reveal year class

composition by numbers and weight of the catches by area.

Sex composition for all areas and also size of the shrimp by

month for Area A are computed. Results of hake stomach

analysis reveal the possibility of a strong 1973 year class

in Area A. The outlook for the 1974 season points out the

need for strong recruitment from the 1973 year class to 

sustain the fishery in all areas.  (12pp.

Aquatic Commons

OCEAN SHRIMP REPORT 
1973 SEASON 1/ 
- 
Nancy E.  Nelson - 2/ 
and 
Walter A. Dahlstrom 3/  
- 
SEVENTEENTH ANNUAL SHRIMP REPORT 
ABSTRACT 
Sta tewide  P a c i f i c  ocean shrimp landings  f o r  1973 a r e  t o t a l e d  
and compared wi th  t h e  1972 season.  Landings by a r e a  a r e  
descr ibed  i n  r e l a t i o n  t o  poundage by month, c a t c h  per  u n i t  
e f f o r t  and f i s h i n g  a r e a .  Sampling r e s u l t s  r e v e a l  yea r  c l a s s  
composition by numbers and weight of t h e  ca t ches  by a r e a .  
Sex composition f o r  a l l  a r e a s  and a l s o  s i z e  of t h e  shrimp by 
month f o r  Area A a r e  computed. Resu l t s  of hake stomach 
a n a l y s i s  r e v e a l  t h e  p o s s i b i l i t y  of a s t rong  1973 year  c l a s s  
i n  Area A .  The out look  f o r  t h e  1974 season p o i n t s  o u t  t h e  
need f o r  s t r o n g  recru i tment  from t h e  1973 year  c l a s s  t o  sus- 
t a i n  t h e  f i s h e r y  i n  a l l  a r e a s .  
1/ Marine Resources Adminis t ra t ive  Report No. 4 ,  A p r i l  1974 
- 
2/  Marine Resources Region, 619 Second s t r e e t ,  Eureka, C a l i f o r n i a  
- 
95501 
31 Marine Resources Region, 411 Burgess Drive,  Menlo Park,  
- 
C a l i f o r n i a  94025 
. 
OCEAN SHRIMP REPORT 
1973 SEASON 
C a l i f o r n i a ' s  1973 ocean shrimp l and ings  t o t a l e d  1,240,235 l b ,  a  
decrease  of 1,248,448 l b  from t h e  1972 season when 2,488,683 l b  were 
landed. The decrease  r e s u l t e d  p r i m a r i l y  from reduced l and ings  i n  Area A. 
Area A 
For t h e  t h i r d  succes s ive  year  no r the rn  C a l i f o r n i a  shrimp f i s h e r -  
men f a i l e d  t o  reach  t h e  Area A quota;  t o t a l  l andings  from t h e  a r e a  
amounted t o  only 979,684 l b .  An a d d i t i o n a l  11,000 l b  were caught i n  
Oregon and d e l i v e r e d  t o  C a l i f o r n i a .  Oregon and C a l i f o r n i a  f ishermen 
caught 714,000 l b  i n  Oregon's Area 19 (Oregon border  t o  t h e  Rogue R ive r ) ,  
b r inging  t h e  t o t a l  c a t c h  from Tr in idad  t o  t h e  Rogue River  t o  1 . 7  m i l l i o n  
l b .  These a r e  t h e  lowest  landings ,  bo th  f o r  Area A and f o r  t h e  combined 
no r the rn  Cal i forn ia-southern  Oregon a r e a  s i n c e  1964. 
The season opened A p r i l  16 w i t h  a p r i c e  t o  t h e  f ishermen of 16$/ lb,  
up 1~ from 1972. Unusually s t r o n g  and prolonged upwelling o f f  t h e  
no r the rn  C a l i f o r n i a  c o a s t  r e s u l t e d  i n  " d i r t y  water" cond i t i ons  which per-  
s i s t e d  through most of June.  The s i x  v e s s e l s  which s t a r t e d  t h e  season i n  
C a l i f o r n i a  went t o  Oregon i n  mid-May a f t e r  f a i l i n g  t o  f i n d  any good con- 
c e n t r a t i o n s  i n  Area A. The p r i c e  was r a i s e d  t o  1 8 ~ / l b  on May 17, bu t  
f i s h i n g  d id  n o t  resume u n t i l  t h e  end of June.  Nearly 80% of t h e  a r e a  
landings  were made dur ing  J u l y  and t h e  f i r s t  h a l f  of August when 10 v e s s e l s  
were f i s h i n g  (Table 1 ) .  A good concen t r a t ion  of shrimp was found o f f  t h e  
Klamath River  and south  i n  50 t o  75 fm (Figure  1 ) .  The p r i c e  w a s  r a i s e d  
aga in  t o  2 0 ~ / l b  on August 5, b u t  fishermen were unable t o  l o c a t e  commercial 
q u a n t i t i e s  of shrimp anywhere between P o i n t  S t .  George and Redding Rock 
i n  40 t o  90 fm. Very l i t t l e  f i s h i n g  occurred  i n  Area A a f t e r  t h e  t h i r d  
week i n  August. 
T a b l e  1. Area A Monthly Shrimp Landings ,  E f f o r t ,  C a t c h l h r ,  V e s s e l  U n i t s ,  
and Number of T r i p s ,  1973 ( C a l i f o r n i a  P o r t s  Only) 
Pounds E f f o r t  
Month l anded  ( h o u r s )  Pounds lh r  Vessels T r i p s  
A p r i l  47,751 77.1 619 6 1 3  
J u n e  57,245 74.8  765 5 14 
J u l y  636,094 994.0 640 11 135 
August 134,382 363.7 369 6 6 4 
September 8,077 61.4 132 6 11 
October  0 0 . 5  0 1 1 
T o t a l s  978,565 1795.8 545* 13** 274 
* Mean 
** T o t a l  v e s s e l s  which made l a n d i n g s  
D e s p i t e  t h e  poor  l a n d i n g s ,  c a t c h l h r  remained r e l a t i v e l y  h i g h .  Each 
t ime  C a l i f o r n i a  f i s h i n g  showed s i g n s  of d ropp ing  o f f ,  most v e s s e l s  immedi- 
a t e l y  l e f t  f o r  Oregon. A s  a r e s u l t ,  a v e r a g e  c a t c h l h r  f o r  t h e  s e a s o n ,  
545 l b ,  was h i g h e r  t h a n  i n  s e v e r a l  p r e v i o u s  s e a s o n s  when more shr imp were  
caught  . 
The 1973 c a t c h  was composed o f  n e a r l y  e q u a l  numbers of 1- and 2- 
year -o ld  shr imp (1972 and 1971 y e a r  c l a s s e s )  d u r i n g  the heavy f ish- ing months 
of J u l y  and August (Tab le  2 ) .  T h i s  is  i n  c o n t r a s t  w i t h  r e c e n t  odd-year 
s e a s o n s  i n  which up t o  80% of t h e  c a t c h  was 1-year-olds ,  and i s  a n  i n d i c a -  
t i o n  o f  a weak 1972 y e a r  c l a s s .  The r e l a t i v e l y  r a p i d  growth and l a r g e  
s i z e  of 1972 y e a r  c l a s s  shr imp ( T a b l e  3) may b e  t a k e n  a s  a f u r t h e r  i n d i c a -  . 
t i o n  of low abundance.  Two-year-old shr imp (1971 y e a r  c l a s s )  were  a l s o  
l a r g e r  t h a n  i n  r e c e n t  y e a r s .  The c o m p a r a t i v e l y  h i g h  p e r c e n t a g e  of p r imary  
females  found d u r i n g  t h e  f a l l  c r u i s e  ( T a b l e  4) i s  c o n s i s t e n t  w i t h  a 
1 , 
I I 
I I 
\ I 
\ I 
B I : 8 01 
s \ 4' 
ld l ' s  
l ' G I  2  
81 t 
l-i 1 
\ 
1 g  
\ \ 
\ I 
"\ I e,; 
\ 
\ \ 
\ \ 
Figure 1 \ \ 
\ 
\ 
\ 
1973 Area A \ \ I I 
I I Ocean Shrimp 
Catch Locations 
Pacific 
Ocean 
1 
\ 
\ 
\ 
\ 
I 
'\ 
I 
\ 
\ 
I 
I 
I 
\ 
\ 
I 
I 
I 
5 miles 
reduced popula t ion  of spawning females.  
Table 2. Area A Count/Pound and Year C la s s  Composition of Shrimp, 
1973 Season 
Age c l a s s  Age c l a s s  
percent  by number percent  by weight 
Month Count/pound 0 I I I 111.  0 I I I I11 
A p r i l  9 8 0.0 18.0 73.6 8.4 0.0 9.3 78.7 12.0 
May 112 0.0 35.7 61.4 2.9 0.0 21.4 73.7 4.9 
June  110 0.0 55.2 43.8 1.0 0.0 37.4 60.6 2.0 
J u l y  99 0.9 48.0 50.5 0.6 0.0 32.9 65.9 1.1 
August 9 0 2.9 44.6 51.7 0.8 0.2 31.2 66.9 1.7 
October* 37.2 47.1 15.6 0.0 
* Shrimp samples from N .  B. SCOFIELD Crab Cru i se  7343-6 
Table 3. Average Carapace Length (mm) of 1- and 2-year-old Shrimp, 
1969-1973 Season 
1 
Season 1969 1970 197 1 1972 1973 
(year  c l a s s )  (1968) (1969) (1970) (1971) (1972) 
A p r i l  12.2 15.2 
June 14.8 15.2 13.6 13.4 16.2 
J u l y  15.2 15.8 14.8 15.0 - 16.7 
August 15.5 16 .3  15.5 15.6 17.3 
September 16.2 16.1 
October 16.6 16.1 18.4 
2 
Season 1969 1970 1971 1972 1973 
(yea r  c l a s s )  (1967) (1968) (1969) (1970) (1971) 
A p r i l  17.4 19.8 
June  
J u l y  
. August 20.8 19.5 21.2 19.3 21.7 
s eptember 21.5 19.6 
October 21.7 19.6 22.5 
Table 4. Year C la s s  and Sex Composition of Area A Shrimp by Month, 
1973 Season (Percentages)  
Males T r a n s i t i o n a l s  Females 
Month 0 I I1 I I1 1 I1 I11 
A p r i l  0.0 16.3 1.5 1.8 36.2 0 .0  35.9 8.4 
June 0.0 39.7 0.1 15.4 24.2 0.0 19.5 1 .0  
J u l y  0.9 29.9 0.0 17.6 23.0 0.5 27.5 0.6 
August 2 . 9  20.2 0.2 23.0 18.6 1 .4  32.9 0.8 
October* 37.2 12.8 0.0 16.4 0.0 18.0 15.6 0.0 
* Shrimp samples from N. B. SCOFIELD Crab Cruise  73-S-6. 
Shrimp samples obtained dur ing  t h e  October c r ab  c r u i s e  (Table 4) 
and t h e  r e s u l t s  of hake stomach a n a l y s i s  (Table 5 )  i n d i c a t e  t h a t  t h e  
1973 year  c l a s s  i s  a s  s t rong  as most even-year c l a s s e s  have been f o r  t h e  
l a s t  10  yea r s .  It appears  t h a t  t h e  t r end  of year  c l a s s  dominance which 
was e s t a b l i s h e d  i n  1964 i s  i n  t h e  process  of being reversed  from even t o  
odd. 
Table 5. Numbers of Shrimp Found i n  P a c i f i c  Hake Stomachs, July-  
October 1973 
Number of shrimp 
Stomachs To ta l  /stomach 
examined Empty* shrimp 0 I I1 I11 Unmeasurable 
* Empty stomachs no t  included i n  c a l c u l a t i o n s .  
The out look  f o r  t h e  1974 season  depends t o  a l a r g e  e x t e n t  on t h e  
s t r e n g t h  of t h e  1973 year  c l a s s  a s  1-year-olds i n  1974, s i n c e  t h e  1971 
and 1972 yea r  c l a s s e s  a r e  n o t  expected t o  c o n t r i b u t e  heav i ly  t o  t h e  f i s h e r y .  
Area B-1 
The only landings  i n  Area B-1 were dur ing  June  when two v e s s e l s  
landed 3,410 l b .  The f ishermen were unable t o  l o c a t e  t h e  shrimp i n  
commercial quan t i t y .  A t o t a l  of 25 tows w a s  made i n  58 t o  90 fm on  
June 12 and 17. Best  ca t ches  were made o f f  Cape Vizcaino a t  dep ths  of 
80 t o  87 fm (Figure  2 ) .  The average  c a t c h l h r  was 254 l b .  L a s t  season  
102,362 l b  were landed. 
Samples from t h e  June  17 shrimp l and ings  revea led  a n  average of 
51.7% 1-year-old, 40.2% 2-year-old and 8.1% 3-year-old shrimp i n  t h e  
ca tches .  Heads-on coun t / l b  averaged 116 wi th  a range of 110 t o  167. 
Two-year-old t r a n s i t i o n a l s  and females  con t r ibu ted  t o  most of t h e  
ca t ch  w i t h  1-year-old males making up t h e  bu lk  of t h e  remainder (Table 6 ) .  . 
Table 6.  Year Class  and Sex Composition of Area B-1 Shrimp, 
1973 Season (Percentages)  
Males T r a n s i t i o n a l s  Females 
Date I I I I I I I I1 I11 
June  17 31.0 9.2 1.2 25.9 0.0 24.7 8.0 
Area B-2 
Two v e s s e l s  t rawled i n  Area B-2 dur ing  t h e  1973 season.  F i sh ing  was 
e x c e l l e n t  and landings  t o t a l e d  246,031 l b  f o r  t h e  per iod  from A p r i l  16 
t o  May 23. The a r e a  was c losed  midnight May 23 because i t  was thought  t h e  
quota of 250,000 l b  would have been reached by then .  Rough s e a s  dur ing  
t h e  a f te rnoon of May 22 and a l l  day on May 23 prevented t h e  v e s s e l s  from 
t rawl ing .  
\ 
\ 
i 
t Figure 2. Area B-1 Ocean Shrimp Catch 
I Locations June 12,  17, 1973 
1 
\ 50 t o  1000 lbs /h r  
\ 
$ Tows l e s s  than 
\ 5 0  lbs /hr  
b \ \ 
s \ /\ 
8 --be \ 
* 
a 
. 
100 fms 
+ 2 Miles 
* 
H 
b 
s 
I 
# 
\ 
# 
I ,\'\\ 
\ I '\, Cape Vizcaino \ \ I \ I 
I I 
t \ 
* 
# 
a \ I I 
; \  \ \ I 
t I 
? \ 
r 
t 
* \ \ 
9O35 ' 
-I- I 1 I I 
f 
I 
3 f I 
t 
I \ 
P a c i f i c  Ocean 
Average c a t c h / h r  f o r  t h e  s e a s o n  was a r e c o r d  2,722 l b ,  more t h a n  
doubl ing  t h e  p r e v i o u s  r e c o r d  f o r  t h e  area of  1 , 1 9 1  l b  s e t  i n  1970. The 
a v e r a g e  c a t c h / h r  by weekly p e r i o d s  ranged  from a low of  1 ,607 l b  f o r  
A p r i l  22-28 t o  a h i g h  of 3,849 l b  f o r  May 6-12 (Tab le  7 ) .  
T a b l e  7. Weekly Shrimp Landings  and E f f o r t  of Area B-2, 1973 Season 
Pounds E f f o r t  
Weekly P e r i o d  l anded  (hours )  Pounds / h r  V e s s e l s  T r i p s  
A p r i l  16-21 48,482 16.2 2,986 2 4 
A p r i l  22-28 19,155 11.9 1 ,607 2 5 
A p r i l  29-May 5 23,808 10.5 2 ,273 2 3 
May 6-12 68,930 17.9 3,849 2 4 
May 13-19 43,776 21.6 2 ,031 2 6 
May 20-23 41,880 12.3  3,396 2 4 
T o t a l s  246,031 90.4 2,722* 2 26 
* Mean 
Shrimp t r a w l i n g  e f f o r t  began o f f  t h e  R u s s i a n  R i v e r ,  t h e n  s h i f t e d  t o  
Duncan's Landing and Salmon Creek a f t e r  two weeks. During t h e  l a s t  week, 
f i s h i n g  r e t u r n e d  t o  o f f  t h e  R u s s i a n  R i v e r  ( F i g u r e  3 ) .  F i s h i n g  d e p t h s  
ranged from 34 t o  47 fm. 
Sampling d u r i n g  A p r i l  r e v e a l e d  a n  a v e r a g e  o f  13.4% 1-year-old,  79.0% 
2-year-old,  and 7.6% 3-year-old shr imp i n  t h e  c a t c h e s .  
Sampling i n  May showed an  a v e r a g e  o f  16.2%,  74.4% and 9.4% of 1-, 
2- and 3-year-old shr imp,  r e s p e c t i v e l y ,  i n  t h e  c a t c h e s  (Tab le  8 ) .  Average 
heads-on c o u n t s / l b  were 98.5  i n  Aprk l  and 96.6 i n  May w i t h  a s e a s o n  
a v e r a g e  97.5. 
Figure 3. Area B-2 Ocean Shrimp Catch 
Locations, 1973 
Russian River 
Duncan ' s Landing 
1 
\ 
\ 
\ 
\ 
\ 
\ 
\ 
Pac i f i c  Ocean \ 
\ 
\ 
I 
I 
I 
1 
b 
I $ 
Table 8. Count Per  Pound and Year Class of Shrimp Composition of Area 
B-2, 1973 Season 
Age c l a s s  % Age c l a s s  % 
Heads-on by number by weight 
Month count / l b  I I I I11 I ' I1 I11 
A p r i l  98.5 13.4 79.0 7.6 7.1 81.6 11.3 
Seasonal  
Average 97.5 14.8 77.7 8.5 7.9 79.7 12.4 
Two-year-old males con t r ibu ted  t o  34.3% of t h e  c a t c h ,  fol lowed by 
2-year-old females (24.7%) and 2-year-old t r a n s i t i o n a l s  (16.7%). One- 
year-old males made up most of t h e  remainder (Table 9). 
Table 9. Year Class  and Sex Composition of Area B-2 Shrimp by Month, 
1973 Season (Percentages)  
Males T r a n s i t i o n a l s  Females 
Month I I1 I I1 I11 I I1 I11 
A p r i l  14.1 38.5 1.1 11.8 0.0 0.0 27.1 7.4 
Seasonal 
Average 15.3 34.3 0.7 16.7 0.05 0.0 24.7 8.3 
Area C 
Only 110 l b  of shrimp were r epo r t ed  t o  have been landed i n  Area C.  
This  occurred on June 21. No informat ion  was a v a i l a b l e  on l o c a t i o n  of 
ca t ch  and e f f o r t .  
Out look 
The outlook for the 1974 season in Area B-2 appears favorable. 
However, because of the relatively weak showing of 1-year-old shrimp 
(1972 year class), a strong 1973 year class will be needed to keep the 
fishing on a sustained yield basis. In Areas B-1 and C, strong re- 
cruitment from the 1973 year class and subsequent year classes is needed 
for increased productivity and sustained yield fishing. 


Ocean Shrimp Report 1973 Season

"pry B J,'.. . -  . 
De;lur. tc :c .-~t  of F i s h  .ri,r>.r; !;t:li;e Mcs., I.ij,;- 
Mari.ne t:esour.ces ~:e,ziori 
OCSh;? B ILR:iP,F i!-KPO3T 
1.972 Seas or, 
by 
OCEAN SHRIXI' REFOXT 1/ 
- 
1972 Season 
by 
Nar~cy E.   el son 
a ~ d  
Walter A. Dahlstrom 
SMTEE2T"TFI mflUAL SKXIMP REPORT 
Cal i fo rn ia ' s  1972 ocean shrimp landings tot.aled 2,488,683 pounds, 
a decrease of 585,857 pounds from t h e  1971 season when 3,074,540 pounds 
were landed. The decrease resu l t ed  pr imar i ly  from t h e  f a i l u r e  of t h e  
vesse ls  t o  reach t h e  quotas i n  Areas A, B-1 and B-2. 
The 1972 shrimp catch from Area A f e l l  considerably shor t  of t h e  
quota f o r  the  second year i n  a row. Northern Ca l i fo rn iz  shrimp f i s h e r -  
men caught 2,126,661 pounds and Oregon vesse ls  landed an a d d i t i o n a l  
137,600 pounds i n  Brookings, bringing t h e  t o t a l  catch from Area A t o  
2,264,261- pounds, near ly  a mi l l ion  pounds shor t  of t h e  3.2 mill-ion pound 
quota. Combined Ca l i fo rn ia  and Oregon landings from Area 13 (0regon boy- 
d e r  t o  t h e  Ilogue ~ i v e r )  amourked t o  1.45 mi l l ion  pounds. The t o t a l  of 
3.7 mi l l ion  pounds caught bekween Trinidad and t h e  Rogue River, Oregon 
i s  only 300,000 pounds l e s s  than t h e  record 1970 landings.  
A t  the request  of ind lx tq j ,  t h e  season opening was advanced 'by t h e  
Prepared a t  Marine Resources Laboratory, Mari.ne Resources Region, 
4.11 Burgess Drive, Menlo Park, Ca l i fo rn ia  94025. 
Fish and Game Commission from May 1 t o  Apri l  16. On Apr i l  19 t he  p r i ce  
was s e t t l e d  a t  15 cents per  pound, up 2 cents from 1971. Fishing con- 
t inued through t he  October 31 cl-osing date,  but the  number of vessels  
engaged i n  the  f ishezy and t h e i r  average catch per  hour f luctuated great-  
l y  from week t o  week tliyoughout t h e  season. During t he  f i r s t  3 months 
of t h e  season t h e  small number (4 or  5) of Cal i fornia  vessels f i sh ing  
regular ly  i n  Area A had dif f icu. l ty  f inding and staying on good concen- 
t ra t ions  of shrimp. Many Cal i fornia  fishermen spent most of t he  season 
i n  Oregon where be t t e r  concentrations of shrimp were avai lable  much of 
t h e  summer. Due t o  t he  l a rge  volune of shrimp being landed a t  Oregon 
por t s ,  many fisher~nen there  were reporteclly f i sh ing  on a recovery basis ,  
so  t h a t  the  ac tua l  p r i ce  across the  docks was subs tan t ia l ly  lower thaii 
15 cents.  .I tie-.s? of C ~ l i f o r ~ i z  vvessel.~ cccurred on +Time 18 when Cal- 
. i f o r n i a  dealers ,  claiming they cculd not ccl~ipete with the  cheaper Oregon 
shrimp, t r i e d  t o  drog t h e i r  p r i ce  t o  .the fishermen, Most Oregon vessels  
stopped f i sh ing  a l so  t o  await the  outcome of the  Cal i fornia  dispute.  As 
a r e s u l t ,  Cal i fornia  d-ealers were forced t o  give in ,  and f i sh ing  was re- 
sumed on Ju ly  5 with t h e  p r i ce  remaining a t  15 cents.  
Catch per  hour and t he  number of vessels  continued t o  flu.ctuate a 
a good deal ,  but both tended i n  general  t o  j.i:crease as t he  season pro- 
gressed  a able 1 ) .  Best f i shing i n  Ju ly  and t h e  f i r s t  pa r t  of August 
was from southwest of Crescentcity t o  thz  Klanath River ( loran L Y ~  1900- 
2000) i n  55 t o  80 fathoms ( ~ i g u r e  1 ) .  Fishihg and weather were poor f o r  
t h e  remainder of August, and a l l  but 3 vessels had returned t o  Oregon 
Tgble  1. Area A Monthly Shrimp Zandings, Effor t ,  Catch Per  Hour, Vessel 
Units, and Number of Trips,  1372 ( ~ a l i f o r n i a  Por ts  ~ n l y )  
Pounds Ef for t  Pounds 
Month landed (hours) per hr. Vessels Trips 
-- - - - - - 
A p r i l  56,757 165. 0 344 9 30 
May 213,724 406.8 525 7 66 
June 159,736 256.7 622 5 47 
Ju ly  531,527 913 2 582 12 125 
~ u g u s t  528,674 953 6 554 13 167 
September 285,447 374.2 763 2- 7 70 
October 356,796 365 5 960 13 99 
Totals 2,126,661 3,435 *(I 619~-  1@-x- 595 
- Mean 
*++ Total  vessels t h a t  made l a d i n g s .  
- 
5 miles 
by the  end of the  month. F ish ing  picked up aga in  i n  mid--September when 
good concent ra t ions  were found i n  t he  a r e a  of Redding Rock i n  45 t o  60 
fathoms. Exce l len t  ca tches  were made i n  t h e  same a r e a  i n  mid-October; 
tows of 2000 pounds per  hour o r  b e t t e r  were common. The average 
ca tch  r a t e  f o r  t h e  season. of 619 pounds per  hour was a cons iderable  
improvement over l a s t  y e a r ' s  450 pounds. 
A s  expected during an even yea r ,  2-year-old t r a n s i t i o n a l s  and fe -  
males (1970 year  c l a s s )  dominated t h e  1972 ca t ch ,  bo th  i n  numbers and 
weight (Tables 2 and 3 ) .  Average count per pound f o r  t h e  sea.son, 121, 
was h igher  than normal f o r  an even year  c l a s s  f i s h e r y ,  due t o  the f a c t  
t h a t  i n d i v i d u a l s  of t h e  1970 year  c l a s s  were smal le r  ( l eng th  and t .~eigi l t )  
than  any shrimp i n  r ecen t  years  (Table 4 ) .  Also, ' 1-year-,old shrimp 
(1971 year  c l a s s ) ,  whtch made up roughly 1 /3  of t h e  ca t ch  f o r  t h e  l a s t  
3 months of the  season, were smal le r  than  normal f o r  an  odd-year--class. 
In  s p i t e  'of t h e  f a c t  t h a t  t he  quota was not  reached i n  Area A ,  
t h e  1970 year  c l a s s  was thought t o  be q u i t e  s t rong .  Oregon f ishermen 
enjoyed a record seasan  of 20 m i l l i o n  pounds, 80 percent  of which were 
2-year-old shrimp. Operat ion of a d e n s i t y  dependent f a c t o r  would appear  
t o  be one poss ib l e  explana t ion  f o r  t h e  r e l a t i v e l y  smal l  s i z e  of both 
1970 and 1971 shrirup. 
A shrimp survey of Area A and southern  Oregon was conducted from 
August 1.-20. Estimated popula t ion  and s i z e  of bed were 3 . 8  m i l l i o n  pounds 
i n  89 square niiles and 2.6 m i l l i o n  pounds i n  50 square mi l e s  f o r  Area A 
Table 2. Area A Count Per P o ~ n d  and Year Class Composition o f  Shrimp, 
1972 Season 
Age Class Age Class 
Percent by Pimber Percent by Weight 
Month ~ o u n t / ~ o u n d  0 1 I1 I11 0 I I T  I11 
A p r i l  137 0.0 7.1 82.7 10.2 0.0 2.6 79.0 18.3 
May 139 0.0 9.4 82.7 8 . 1  0.0 3.6 81.4 15.0 
June 12 5 0.0 7.7 86.0 6 .3  0.0 3.2 84.7 12 .1  
~ u l y  115 0.0 16.1 80.6 3.3 0.0 9.8 84.6 5.6 
A U ~ U S ~  113 0.0 29.8 68.6 1.6 0.0 18.6 78.2 3.2 
August* 0.3 25.2 70.2 4.3 
September 109 0.8 34.4 64.4 0.5 0.0 23.9 75.1 0.9 
October 101 0 .1  2 . 2  57.2 0.3 0.0 2.1 70.3 0.6 
. October*E 45.6 28.8 25.2 0.4 
* Shrimp sanpl-es from N. B, Scof ie ld  Shrjmp Cruise 72-S-6. 
** Shrimp samples from N. B. Scor'ield CI-a,b C-c-uise 72-S-8 
Table 3. Year Class and Sex Co~:g~sit!.o:l of Arer. A Shrimp by Month, 
1972 Season (~ercenta:;es ) 
Males Transitional s Females 
Month 0 :C I1 I I1 I I1 III 
A p r i l  0.0 7.1 4.0 0.0 41.4 0.0 37.3 10.2 
May 0.0 9.4 4.7 0.0 46.7 0.0 31.1 8.1 
June  0.0 7.1 3.7 0.4 42 a r( 0.2 39.6 6 3 
July 0.0 14.4 4.0 1.5 43 - 9 0.0 32.7 3.3 
AU~US-L 0.0 24.6 2.6 5.0 3 ° C  7 0.1 31-3 1.6 
September 0.8 26.3 1.8 7.4 23.0 - 0.2 39.5 0 5 
October 0.1 25.9 0-0 16.3 6.5 0.0 50.8 0.3 
T a b l e  4. Average Carapace Length (m) of 1-a~d-2-Year 0:Ld Shrimp 
1969- 1972 Seasons 
Season 1969 1970 1971 1972 1569 1970 1971 1972 
(year c l a s s )  (1968) (1963) (1970) (1971) (1967) (1968) (1969) (1970) 
A p r i l  12.21 17.41 
June 14.75 15.21 13.53 13.41 20.6 18.75 20.14 1'7.911 
J U ~ Y  15.19 15.76 1b,82 14.99 20.7 19.10 20.83 18.78 
A U ~ U S ~  15.46 16.34 15.43 15.61. 20.8 19.52 21.18 19.26 
September 16.24 16.06 21.49 19.69 
Octo'ber 16.56 16.07 21.68 19..63 
and Area 19 respect ive ly ,  giving a combined t o t a l  of 6.4 mi l l ion  pounds 
i n  139 square miles.  P r i o r  t o  t h e  survey approximately 1 mi l l ion  pounds 
had been landed from each of t h e  2 areas .  The f igures  f o r  Area 1 9  a r e  
not  s t r i c t l y  cornpayable t o  those of prevl.ous surveys; 2 new s t r a t a  w2re 
add.ed t h i s  year  a t  t h e  northern end of t h e  area,, and these  2 s t r a t a  con- 
t r i b u t e d  1 million pounds t o  t h e  popula'ti.on est imate.  However, t h e  s i z e  
of t h e  shrimp bed i n  Area P, was t h e  smal les t  f o r  t h e  l a s t  5 summey and 
f a l l  c ru i ses ,  and t h e  population est imzte was t h e  lowest s ince  1966. 
Since t h e  1971 year  c l a s s  was r e l a t i v e l y  >real<, s t rong  recrui tment 
of t h e  1972 year  c l a s s  i s  necessary t o  ca r ry  t h e  f i s h e r y  through t h e  
1973 and 1974 seasons. Surveys conducted during l a t e  sumner of 1-966 and 
1963 yielded b e t t e r  than 60 percent  by number of incoming yea r  c l a s s  
, 
shrimp which subsequently su2ported t h e  f i s h e r y  f o r  2 years  i n  a row. 
Samples from t h i s  yea r ' s  survey contained on1.y 0 .3  percent  by nulmber of 
1972 year  c l a s s  shrimp. However, 45.6 percent  of t h e  shrimp caught dur- 
ing the  October crab c ru i ses  were juveni les ,  ind ica t ing  t h e  p o s s i b i l i t y  
of a l a t e  hatch r a t h e r  than poor recrui tment.  
P a c i f i c  hake stomach contents  exa.mined between J u l y  and October con- 
ta ined unusua.lly low nudber of a l l  age c l a s ses  of  shrimp, with only 0.05 
juveni le  shrimp p e r  stomach  a able 5) .  However, 65 percent  of  the  t o t a l  
hake exami.ned were caught during t h e  August survey. Hake caught i n  Oc- 
tober  had 0.4 juveniles  per  stomach, wblch i s  a somewhat b e t t e r  showing 
'but s t i l l  only 1/2 t o  1/3 as many as  during t h e  l a s t  3 even years .  
Table 5. ru'unibers o f  Shrimp Found i n  P a c i f i c  Hake Stomaclis 1972 
No. o f  Number of Shrimp 
Stomachs Ro. of  pe r  stomach 
Period Examined Empty+ Shrimp 0 I I1 111 Unmeasurable 
July-Oct. 407 59 195 0.5 0.13 0.22 0.01 0.16 
Wmpty stomachs not  included i n  c d c u l a t i o n s .  
In  .view of t h e  r e l a t i v e l y  high landinss  .from southe:rn Oregon and t i le 
small  simber of  vesse l s  f i s h i n g  i n  Area A f o r  much of t h e  seasor! it i s  
poss ib le  t h a t ,  a s  i n  1971, f a i l u r e  t o  reach t h e  quota t h i s  year  was a re-  
f l ec t io r ,  of low a v a i l a b i l i t y  of shrimp o f f  C:alifornia, rat t ler  than of a 
reduced population. On t h e  o the r  hand., t h e  r e s u l t s  of t h e  summer survey, 
t h e  ind ica t ions  of poor3r than liorrnal recruj.tment, and t h e  f a c t  t h a t  good 
commercial f i s h i n g  was concentrated i n  small  a reas  f o r  much of t h e  season 
a l l  seem t o  point  t o  t h e  poss i ' b i l i ty  t h a t  t h e  Area A population i s  down. 
In  any case, t h e  resoilsce should be closely watched, especially during the 
e a r l y  months of t h e  1973 season. 
Three vesse l s  landed 102,362 pourids from May 21  t o  June 28. No f i s h -  
ing took p lace  a f t e r  June 28 'because. t h e  fishermen were unable t o  l o c a t e  
t h e  shrimp i n  commercial quan t i ty  and reach t h e  quota of 250,000 pounds. 
This  season 's  landings were t h e  h ighes t  s ince  1961 when 799,427 pounds 
were Landed. The average catch p e r  hour was 1,125 pounds f o r  the season. 
2 Miles F - 4  
with a low of 539 pounds pe r  hour during May and a high of 1,213 pounds 
during June  a able 6 ) .  
Table 6. Area B - 1  Mont:ily Shrimp Landings and E f f o r t  1972 
Month Landed 
Pounds 
E f f o r t  per  
(hours ) Hour Vessels Tr ips  
May 6,515 
June 95,847 
T o t a l s  102,362 91.1 1 , 12 3-* 3"CSC 25 
++ Mean 
T o t a l  vesse l s  tha'i rnade l e ~ d i n s s  
Fishing e f f o r t  was concentrated mainly off  Usal i n  54 t o  74 fa.tl.ioms 
( ~ i g u r e  2 ) .  Catch sanl~line;  .during June revealed an average of 52.5 per- 
cent  one-year-old shrimp i n  t h c  c~rLchea able 7) .  Average he'ads-on counts 
per pound ranged from 1-02 t o  150 with a sesson average of  135. 
Table 7. Area B-1 Count p e r  Pound a ~ d  Year Class Composition of  Shrirop 1972 
- 
ilse Class Pze Class 
Heals-on Percent  by 3umber Percent by Wgt. 
Date Count pe r  Pound I I1 I11 'I: I1 111 
June 8 142 55.7 42.7 1.6 35.6 61.3 2.9 
June 27 
Seasonal  Avg. 135 52.5 45.4 2.1 34.0 62.4 3.6 
- - 
One-year-cld males md t ; rzr is i t ionals  cont r ibuted  most o f  t h e  c a t c h  
with two-year-old t r a n s i t i o n n l s  and females making up t h e  b u l k  of  t h e  re- 
mainder  a able 8). 
Table 8. Year Class and Sex Conlpc\sition of Area B - 1  Shrimp, 1972 Season 
(percentages) .  
Males T r a n s t t j  onals  Females 
Date I I1 I I I I I1 111 
June 8 30.9 0.0 24.6 24.3 0 . 3  18.3 1.6 
June 27 32.6 2.7 16.7 24. 9 0 . 3  20.4 2 .7  
- -- 
AREA B-2 
Four ves,sels lended 213,1+52 po7mds during April, Kay, June axid A-ag- 
u s t .  Landings were s p o r a d i c  and a t  t imes t h e  fishermen ceased f i s h i n g  
becacse they were unaJble t o  f ind  t h e  shrimp i n  commercial q~~.ant i ty .  No 
f ishi i ig took p lace  a f t e r  August 2 1  and consequently t h e  fishermen were 
u n a b l e  t o  reach t h e  quota of 250,000 po-uids. 
Average c a t c h  p e r  hour f o r  t h e  season  w a s  1 ,182 p o u n d s , ' n e a r l y  
approach ing  t h e  r e c o r d  .average c a t c h  p e r  hour f o r  t h e  a r e a  o f  , , , I 9 1  pounds 
s e t  i n  1970. Average c a t c h  p e r  hour  by month from a  low o f  340 pou l~ds  
f o r  June  t o  a high of 1,515 pounds f o r  k d g t l s t  (Table  9)  . 
Table 9. Area B-2 Monthly Shrimp Landings a.na Ef for t  1972. 
- 
Pounds 
Pounds Ef for t  Per 
Month Landed (hours) Hour Vessels Trips 
Apri l  30,279 22.4 1,353 
May 90,797 95 * 2  953 
June 7 850 2.5 * 340 
August 91,526 60.4 1,515 
Totals  213,452 180.5 1,1823~ 4369 42 
* Mean 
- Tota l  vessels t h a t  nede 1.andings. 
E'ishing efi'or-t s t a r t ed  oi'f Fork El.~s  a14 Sai'c Foiilt dui-itlg A-pril, 
May and June but shifi;ed t o  the  north @if S a l t  l o i ~ l t  and Horseshoe Point 
during ( ~ i ~ u r e  3 ) .  Fishing depths ranged from 45 t o  69 fathoms 
with best catches made i n  depths rangicg from 48 t o  57 fa thom.  
Sanpling during A p r i l  revealed an average of 36.3 percent one-year- 
01-d shrimp and 61.8 percent two-year-old shrimp in the catches whereas 
August sampling showed 6'7.4 percent one-year-old ar_d 32.3 perccnt two- 
year-old shrim:p i n  t he  catches ( ~ e b l e  10). Average heads-on counts per  
pound were 133 i n  April  and 118 in  August with a season average of 125 

Table 10. Area B-2 Count per Pound and Year Class Composition of Shrimp 
1972 Season 
Month 
Heads-on 
Count per Pound 
Age Class Age Class 
Percent by No. Percent by No. 
I TI 111 I I1 I11 
Apri l  133 - 36.3 61.8 1.9 24.14 71.8 3.8 
August 118 67.4 32.3 0.3 55.1 44.3 0.6 
- - -- - 
Seasonal Average 125 51.9 117.0 1.1 33.8 58.0 2.2 
One-year-old males and two-year-old Per~ales contributed t o  most of 
the  catch with one-yea,r nnd two-.gear-o1.d t rwsi t jonr l l .  shr imp rnakinq up 
. most of the  remainder  a able 11). 
Table 11. Year Clas:; and Sex Co::~p.-position of  Area B-2 Sliriap by Month, 
1372 Season (-percent=es) 
Date 
Males Trans i t  ionals 
I I I I I1 
Females 
I I1 I11 
-- ---- --" 
April  32 5 14.3 3 9 7.5 -9  0.0 31.6 1.8 
August 40.7 0.0 16.6 13.6 10.5 18.2 0.3 
The outlook f o r  t h e  2.973 season i n  Areas B-1, B-2 and C i s  question- 
able .  The populations appear t o  be r e l a t i v e l y  small  and no l a r g e  popula- 
t i c n  build-up has been observed. Strong recrui tment from t h e  1972 year  
c l a s s  arid subsequent year-c lasses  i s  needed f o r  increased p roduc t iv i ty  and 
sustained y i e l d  f i sh ing .  


Ocean shrimp report 1972 season

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Ocean shrimp report 1972 season

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