During the period October 1 - December 31, 1973, Fall surveys of permanent subtidal stations were completed with one station being surveyed. We were unable to locate 3 

subtidal stations.

Intertidal studies were initiated in November. A total of 12

random stations was surveyed.

Interviews were conducted with commercial abalone fishermen

working between Pt. Buchon to Pecho Rock. We continued to

monitor the sea otter herd foraging between Pt. Buchon and

Lion Rock.

Progress was achieved in the abalone temperature tolerance

studies when a successful spawning occurred. (20pp.

Ebert, Earl E.

Gotshall, Daniel W.

Laurent, Laurence L.

English

Aquatic Commons

T h i s  r e p o r t  i s  t h e  second q u a r t e r l y  r e p o r t  s u b m i t t e d  i n  p a r t i a l  
f u l f i l l m e n t  of Research C o n t r a c t  No. 68-1047 between t h e  Department 
of F i s h  and Game and t h e  P a c i f i c  Gas and E l e c t r i c  Company. Through 
t h i s  c o n t r a c t  t h e  Department of F i s h  and Game i s  t o  conduct  e c o l o g i c a l  
m o n i t o r i n g  s t u d i e s  t o  de te rmine  what changes ,  i f  any,  have o c c u r r e d  
i n  t h e  b a s e  l i n e  i n v e n t o r y  of t h e  marine  b i o t a  w i t h  s p e c i a l  r e f e r e n c e  
t o  f i s h  and t o  aba lone  conducted d u r i n g  1970 and 1971. 
Q u a r t e r l y  r e p o r t s  w i l l  b e  fol lowed by a n n u a l  r e p o r t s .  F u l l  
t a b l e s  and s p e c i e s  l i s t s  w i l l  b e  i n c l u d e d  i n  each  a n n u a l  r e p o r t .  
Submit ted t o :  
Bar ton  W. S h a c k e l f o r d ,  Vice P r e s i d e n t  
P l a n n i n g  and Research 
P a c i f i c  Gas and E l e c t r i c  Company 
77 B e a l e  S t r e e t  
San F r a n c i s c o ,  C a l i f o r n i a  
Submit ted by: 
Doyle E .  Gates  
C a l i f o r n i a  Department o f  F i s h  and G a m e  
Marine Resources  Region 
350 Golden Shore  
. Long Beach, C a l i f o r n i a  
DIABLO CANYON POWER PLANT SITE ECOLOGICAL STUDY 
QUARTERLY REPORT No. 2 L/ 
by 
Danie l  W. Go t sha l l ,  
Laurence L. Laurent and 
E a r l  E. Ebert  21 
- 
ABSTRACT 
During t h e  per iod  October 1 - December 31, 1973, F a l l  surveys  
of permanent s u b t i d a l  s t a t i o n s  were completed wi th  one s t a t i o n  
being surveyed. We were unable t o  l o c a t e  3 s u b t i d a l  s t a t i o n s .  
I n t e r t i d a l  s t u d i e s  were i n i t i a t e d  i n  November. A t o t a l  of 12 
random s t a t i o n s  was surveyed. 
In te rv iews  were conducted wi th  commercial aba lone  f ishermen 
working between P t .  Buchon t o  Pecho Rock. We continued t o  
monitor  t h e  s e a  o t t e r  herd foraging  between P t .  Buchon and 
Lion Rock. 
P rog res s  was achieved i n  t h e  abalone temperature t o l e r a n c e  
s t u d i e s  when a s u c c e s s f u l  spawning occurred. 
11 Marine Resources Adminis t ra t ive  Report 74-3, February 1974 
- 
2 /  Marine Resources Laboratory,  Marine Resources Region, 2201 Garden Road, 
- 
Monterey, C a l i f o r n i a  93940. 
INTRODUCTION 
During t h e  q u a r t e r  we completed f a l l  surveys  of t h e  permanent sub- 
t i d a l  t r a n s e c t s ,  began s t u d i e s  i n  t h e  i n t e r t i d a l ,  began in t e rv i ewing  
commercial abalone d i v e r s ,  and cont inued monitor ing t h e  s e a  o t t e r  herd 
loca t ed  sou th  of P o i n t  Buchon. A t o t a l  of 53 man-days was spen t  a t  t h e  
s i t e  during t h e  q u a r t e r .  
OPERATIONS 
One permanent s u b t i d a l  s t a t i o n  was surveyed i n  October,  b u t  we were 
unable t o  survey  t h r e e  of t h e  permanent t r a n s e c t s  due t o  boa t  breakdowns 
and rough ocean cond i t i ons .  Counts of red abalone,  abalone p r e d a t o r s  
and compet i tors  a t  s u b t i d a l  S t a t i o n  15 were very  c l o s e  t o  those  obta ined  
by Burge and Schul tz  i n  October 1971 (Table 1 ) .  I n  1971, 6  r ed  aba lone ,  
4 Cancer antennarius and 212 StrongyZocentrotus franciscanus were ob- 
served on t h e  s t a t i o n ;  counts  f o r  t h e  same animals i n  1973 were 4 ,  5 
and 289 r e s p e c t i v e l y .  
During t h i s  q u a r t e r ,  random i n t e r t i d a l  s t a t i o n s  were e s t a b l i s h e d  
i n  Diablo Cove and i n  an a r e a  about  2.5 km (1.6 mi l e s )  n o r t h  of t h e  cove 
(F igure  1 ) .  Diablo Cove, where t h e  o u t f a l l  i s  l o c a t e d ,  was d iv ided  i n t o  
t h r e e  d i s c r e e t  a r e a s :  North Diablo Cove I n t e r t i d a l  (NDCI), South Diablo 
Cove I n t e r t i d a l  (SDCI) and Diablo Po in t  I n t e r t i d a l  (DPI). Each of t h e  
a r e a s  was d iv ided  i n t o  n i n e  s t a t i o n s .  The s tudy  a r e a  t o  t h e  n o r t h ,  North 
Control  I n t e r t i d a l  (NCI), i s  loca t ed  ad jacen t  t o  F i e l d ' s  Ranch p rope r ty  
and c o n s i s t s  o f - 2 0  s t a t i o n s .  The method of s tudy  i s  t h e  same a s  was 
e s t a b l i s h e d  f o r  t h e  Mendocino s t u d i e s  (Go t sha l l ,  e t  a l ,  1973). S t a t i o n s  
2 
a r e  chosen randomly and f o u r  it m2 (2.7 f t  ) quadra t s  a r e  sampled along a 
TABLE 1. Comparative Counts o f  S e l e c t e d  I n v e r t e b r a t e s  a t  S u b t i d a l  
S t a t i o n  15 - Diablo Canyon - October  1971  and October  1973. 
Spec i e s  1971 Count 1973 Count 
HaZiotis rufescens 6 
Cancer antennarius 4 
Py cnopodia he Ziant hoides 3 
'StrongyZocentrotus franciscanus 212 
Scorpaenichthys marmorntus 0 
North 
Control 
Intert idal  
Field's Ranch 
Property / 
/ 
/ 
/ 
/ 
/ 
/ 
/ 
/ 
/ 
/ 
/ 
P G & E  
Atomic Energy 
P lan t  S i t e  
North  Diablo Cove 
Inter t ida l  
South Diablo Cove 
In te r t ida l  
Diablo Point 
FIGURE 1. I n t e r t i d a l .  s t u d y  a r e a s  a t  Diablo  Canyon. 
l i n e a r  30 m (98 f t )  t r a n s e c t .  A t  each quadra t  a l l  macro-invertebrates  
a r e  counted, a l l  s o f t  a l g a e  c o l l e c t e d  f o r  l a t e r  q u a n t i f i c a t i o n ,  and t h e  
percent  cover by a r t i c u l a t e d  c o r a l l i n e s  and PhyZlospadiz scouZeri e s t i -  
mated. Also, abalone a r e  counted w i t h i n  one meter t o  e i t h e r  s i d e ,  and 
along t h e  t o t a l  l eng th ,  of t h e  30 m (98 f t )  l i n e .  
A t o t a l  of 12 i n t e r t i d a l  s t a t i o n s  was v i s i t e d  dur ing  t h e  q u a r t e r :  
9 i n  Diablo Cove and 3 i n  t h e  North Cont ro l  Area. The i n v e r t e b r a t e  
d a t a  from t h e s e  s t a t i o n s  have been summarized (Table 2 ) .  The numbers of 
red  and b lack  abalone counted along t h e  t r a n s e c t s  w i t h i n  t h e  cove ranged 
from ze ro  t o  180 (Table 3 ) .  Thus f a r ,  b lack  abalone have occurred wi th  
a mean of 0.612/m2 and r e d s  wi th  a mean of 0.147/m2 i n  t h e  cove. 
The a l g a e  c o l l e c t e d  from t h e  quadra ts  a r e  being worked up f o r  bio- 
mass i n d i c e s  a s  t ime al lows.  
With t h e  i n c r e a s e  i n  commercial abalone d i v i n g  i n  t h e  Diablo Canyon 
a r e a ,  we began in te rv iewing  conunercial abalone d i v e r s  t o  determine f i s h -  
ing  a r e a s  and catch-per-uni t -of-effor t .  
During t h e  q u a r t e r  we interviewed d i v e r s  from 14 b o a t s ,  t h e i r  c a t c h  
amounted t o  966 red  abalone. The average d a i l y  landing was 69 red  abalone 
(Table 4) .  Most of t h e  d iv ing  e f f o r t  was focused on t h e  a r e a  from Pecho 
Rock t o  Po in t  Buchon. 
Sea o t t e r s  were counted a t  l e a s t  once each week. Counts ranged 
from a low of 8 on October 22 t o  a h igh  of 87-90 animals on August 20 
(Table 5) .  Most of t h e  o t t e r s  t h a t  were feeding  were e a t i n g  r ed  o r  b l ack  
abalone. No o t t e r s  have been observed dur ing  16 surveys  ( J u l y  20 through 
December 24, 1973) of t h e  a r e a  between Lion Rock and Po in t  San Luis.  
0 0 0 
m o o  
N m m  
0 0 0  
P. 0 CO 
o m o  
,TLULE 2 (cont  .) . 
NDCI SDCI DP I NCI 
Species  Sum Percent  Mean Sum Pe rcen t  Mean Sum Pe rcen t  Mean Sum Pe rcen t  Mean 
frequency frequency frequency frequency 
ECBINODElLX4TA (cont  . ) 
Pisaster ochraceous 1 12.5 0.12 
Strongy loccntrotus pwpuratus 2 16.6 0.17 1 6.2 0.06 33 37.5 4.12 2 20.0 0.20 
TWICATA 
CZave Zina hmtsmani 1 8 . 3  0.08 3 6.2 0.19 
TOTAL % m2 QUADRATS 12 1 6  8 

TABLE 4 .  Summary of Commercial Abalone F i s h e r y  I n t e r v i e w s  - P o i n t  Buchon t o  P o i n t  San L u i s  - 
October through December 1973. 
Date Numbers of b o a t s  Hours Landings of r e d  a b a l o n e  
sampled f i s h e d  Number Average weigh t  S i z e  range (mm) 
October 1, 1973 
October 4 ,  1973 
October 5 ,  1973 
October 9 ,  1973 
October 10,  1973 
October 16,  1973 
October 17,  1973 
October 18 ,  1973 
November 5 ,  1973 
December 4,  1973 
TOTALS 
MEANS 
TABLE 5. Suminary of Sea Otter Counts and Feeding Hab i t s  - 
Poin t  Buchon t o  Lion Rock - July through December 1973.  
Date O t t e r  
count Number observed feeding  Abalone Urchins Crabs Unid. Misc. 
J u l y  1 6 ,  1 9 7 3  26 
August 2,  1973  
August 6 ,  1 9 7 3  
August 1 3 ,  1973  
~ u g u s t  20 ,  1973  
October 2 ,  1973  
October 8,  1 9 7 3  
October 1 5 ,  1 9 7 3  
October 22 ,  1 9 7 3  
November 5 ,  1973  
November 1 4 ,  1973  
November 1 9 ,  1973  
November 26,  1973  
December 4 ,  1973  
December 11, 1973 
December 18, 1973 
December 28, 1973  
ABALONE TEIPERATURE TOLERANCE STUDIES 
A sample of a d u l t  r ed  abalones was obta ined  from t h e  Diablo Canyon 
reg ion  i n  October. Specimens from t h i s  sample e x h i b i t i n g  r ep roduc t ive  
ma tu r i t y ,  a s  evidenced by gonadal bulk,  were placed i n  a s e p a r a t e  r e se r -  
v o i r  and condi t ioned  f o r  spawning. 
A s u c c e s s f u l  s p a w i n g  was achieved on November 30 a t  a  temperature 
of 15.5C (59.9F). Developing embryos were c o l l e c t e d  a t  t h e  4 and 8 c e l l  
s t a g e  (approximately 2 t o  3 hours  p o s t - f e r t i l i z a t i o n ) .  Cu l tu re s  were 
e s t a b l i s h e d  and maintained i n  15  l i t e r  (4 g a l )  p l a s t i c  c o n t a i n e r s  a t  10C, 
15C and 20C (50F, 59F and 68F r e s p e c t i v e l y ) .  
Temperature t e s t s  were performed i n  d u p l i c a t e  s e r i e s  of f i n g e r  bowls, 
each con ta in ing  a  f i n a l  volume of 300 m l  of f i l t e r e d  seawater .  Tes t  
animal d e n s i t i e s  were c a l c u l a t e d  by t h e  a l i q u o t  technique ,  a f f o r d i n g  an 
approximate equal  number of t e s t  animals pe r  u n i t  volume, f o r  each f i n g e r  
bowl. Ins tan taneous  t e s t  t empera tures  were obta ined  by prede termina t ion  
of t h e  temperature of t h e  seawater  needed, by volume, t o  produce t h e  
d e s i r e d  t e s t  temperature when mixed w i t h  t h e  t e s t  animal a l i q u o t .  
Tes t  temperatures  were s e l e c t e d  a t  va r ious  e l e v a t i o n s  up t o  1 1 C  
(19.8F) above each acc l imat ion  temperature (lQC, 15C o r  20C) s o  a s  t o  en- 
compass t h e  maximum temperature e l e v a t i o n s ,  above ambient,  a n t i c i p a t e d  
i n  Diablo Cove. 
A s e r i e s  of temperature t o l e r a n c e  t e s t s  was conducted t o  s imu le t e  
t h e  entrainment  t ime expected through t h e  cool ing  water  system planned f o r  
Diablo Canyon. These t e s t s  cons i s t ed  of exposing t e s t  animals  t o  tempera- 
t u r e  e l e v a t i o n s  f o r  1 minute.  Immediately a f t e r  1 minute t h e  t e s t  
animals were r e tu rned  t o  acc l imat ion  temperature water  ba ths .  
Observat ions of t e s t  animals  were made a t  2, 4 ,  6  and 8 hour i n t e rva l s .  
Observat ions were te rmina ted  a f t e r  48 hours .  
Temperature t o l e r a n c e  tests were f i r s t  accomplished w i t h  t h e  embryos 
being acc l imated  a t  15C (59F). These embryos had ob ta ined  t h e  morula 
s t a g e  (16 t o  32 c e l l s :  6 t o  7 hours  o ld )  when t e s t i n g  i n i t i a t e d .  Tes t  
animals  were exposed t o  tempera ture  e l e v a t i o n s  up t o  26C (78.8F). 
No m o r t a l i t y  was observed f o r  t h e  s imula ted  entrainment  t i m e  tests 
throughout  t h e  48 hour obse rva t ion  per iod .  However, long term (48 hour) 
e l eva t ed  temperature  exposures  d i d  cause some m o r t a l i t i e s .  
Aberrant  embryo development was noted a f t e r  a 6 hour exposure t o  
temperatures  of 25C and 26C (77F and 78.8F r e s p e c t i v e l y ) ,  Normal develop- 
ment d i d  no t  proceed t o  t h e  t rochophore l a r v a l  s t a g e  a t  26C (78.8F), 
a l though t h e  b i z a r r e  forms t h a t  r e s u l t e d  d i d  e x h i b i t  c i l i a r y  movement and 
locomotion. A t  25C (77F),  17% of t h e  tes t  an imals  ob ta ined  a normal 
t rochophore s t a g e  a f t e r  1 0  hours '  exposure;  however, no animals  developed 
t o  t h e  v e l i g e r  l a r v a l  s t a g e ,  and a l l  t e s t  animals  succumbed a f t e r  a 42 
hour exposure.  Tes t  t empera tures  of 23C (73.6F) and below d i d  n o t  impair  
l a r v a l  development no r  e f f e c t  any m o r t a l i t y  (Table 7) .  
Tes t  animals acc l imated  a t  20C (68F) had reached t h e  v e l i g e r  l a r v a l  
s t a g e ,  and were approximately 56 hours  o ld  when t e s t i n g  began. I n  t h i s  
s e r i e s  of temperature  t o l e r a n c e  tests t h e  l a r v a e  were exposed t o  a maxi- 
mum temperature  of 31C (87.8F). Unfo r tuna t e ly  t h e  t e s t s  had t o  be  t e r m i -  
na t ed  a f t e r  26 hours  due t o  an e r r o r  made i n  t h e  a l i q u o t  l a r v a l  sample 
e s t ima te .  Cu l tu re  d e n s i t i e s  were approximately 3 t o  4 t.irnes t h e  d e s i r e d  
number, causing a deg rada t ion  i n  water  q u a l i t y ,  and l a r v a l  m o r t a l i t y .  
No m o r t a l i t y  was observed f o r  v e l i g e r  s t a g e  l a r v a e ,  acc l imated  a t  20C 
(68F), and sub jec t ed  t o  t h e  s imula ted  entrainment  t es t ,  throughout t h e  26 
hour obse rva t ion  per iod .  However, long term (26 hour)  e l e v a t e d  tempera ture  
exposure t e s t s  d id  e f f e c t  m o r t a l i t y  a t  t h e  h ighe r  tempera ture  e l e v a t i o n s .  

After  a  2 hour exposure t o  tempera tures  of 30C and 31C (8hF and 87.8F 
r e s p e c t i v e l y ) ,  t e s t  animals  were extremely weak and s l u g g i s h ,  e x h i b i t e d  
f e e b l e  c i l i a r y  movement, and remained on t h e  bottom of t h e i r  c u l t u r e  bowls. 
Tes t  animals  he ld  f o r  a  similar per iod  of t ime a t  27C (8q.6F) e x h i b i t e d  
f a i r  c i l i a r y  movement, bu t  a l s o  remained on t h e  bottom o f - t h e i r  c u l t u r e  
bowls. A t  25C (77F) and lower tempera tures  t h e  t e s t  animals  were a c t i v e  
and swimming. 
M o r t a l i t y  ensued a f t e r  a  10 hour exposure a t  31C (87.8F). A l l  t e s t  
animals he ld  a t  t h i s  tempera ture  d i ed  a f t e r  a  14 hour exposure. It took 
22 hours  f o r  t h i s  cond i t i on  t o  o b t a i n  a t  a  temperature of 30C (86F) 
(Table 8 ) .  
Vel iger  s t a g e  l a r v a e  accl imated a t  10C (50F) were approximately 125 
hours  old when temperature e l e v a t i o n  t e s t s  began. The l a r v a e  had n o t  y e t  
obtained t h e  benthonic,  c reeping  s t a g e ,  due t o  t h e  depressed c u l t u r e  
temperature.  
Tes t  animals were exposed t o  maximum temperature e l e v a t i o n s  of 21C 
(h9.8F) f o r  48 hours.  However, no m o r t a l i t y  was observed throughout t h e  
obse rva t iona l  per iod f o r  e i t h e r  t h e  s h o r t  term ( 1  minute entrainment  
s imu la t ion  t ime a t  maximum temperature e l e v a t i o n ) ,  o r  t h e  long term 
(48 hour) exposure. 
TABLE 8 .  P e r c e n t  S u r v i v a l  of V e l i g e r  S t a g e ,  Red Abalone,  HaZiotis 
rufescens, Accl imated a t  20 C and S u b j e c t e d  t o  I n s t a n t a n e o u s  
E l e v a t e d  Temperature  Shock. 
T e s t  No. of P e r c e n t  S u r v i v a l  
temp. OC t e s t  Exposure t i m e ,  hours  
an imals  
2  6 1 0  1 4  18 2 2 26 
MAN-DAYS SPENT AT DIABLO CANYON POWER PLANT S I r E  
O c t o b e r  1 - December 31, 1 9 7 3  
Sub t i d a l  S u r v e y s  : 
Octobe r  11 - 1 2  
P a r t i c i p a n t s :  G o t s h a l l ,  L a u r e n t ,  Benech 
December 1 0  
P a r t i c i p a n t s :  G o t s h a l l ,  L a u r e n t ,  F a r r e n s  
I n t e r t i d a l  S u r v e y s :  
O c t o b e r  2 8  - 29 
P a r t i c i p a n t s :  G o t s h a l l ,  L a u r e n t  , Benech 
November 9 - 1 2  
P a r t i c i p a n t s :  G o t s h a l l ,  L a u r e n t ,  Benech 
December 7  - 1 0  
P a r t i c i p a n t s :  G o t s h a l l ,  L a u r e n t ,  F a r r e n s ,  Benech 
December 20 - 2 3  
P a r t i c i p a n t s :  Benech,  F a r r e n s  
Commercial Abalone  F i s h e r y  S u r v e y s :  
O c t o b e r  1, 4 ,  5 ,  9 ,  1 0 ,  1 6 ,  1 7 ,  18 
November 5  
December 4  
P a r t i c i p a n t s :  Benech 
S e a  Otter S u r v e y s :  
O c t o b e r  2 ,  8 ,  1 5 ,  22  
November 5 , 7 ,  1 4 ,  1 9 ,  26 ,  29 
December 4 ,  11, 1 8 ,  24,  28  
P a r t i c i p a n t s  : Benech 
T o t a l  tian-Days dur ing  q u a r t e r  
T o t a l  Nan-days a t  s i t e  
Boat-Days l o s t  t o  breakdown 
T o t a l  s t a t i o n s  surveyed 
Trave l  t i m e  Man-Days 
Boat t i m e  (hours)  
Laboratory t i m e  Man-Days 
*Non-project personnel  Man-Days n o t  included i n  t o t a l s ,  and 
t o t a l s  do n o t  i n c l u d e  t i m e  spen t  on abalone tempera ture  t o l e r a n c e  
s t u d i e s .  
PROJECT PEKSONMEL 
Daniel  W. Go t sha l l  
Laurence L. Laurent 
Margaret M. Hughes 
Suzanne V. Benech 
John R. Glabe 
Gary D. Far rens  
E a r l  E. Ebert  
E. E. Mart indale  
Kenneth Boet tcher  
Senior  Elarine B io log i s  t -P ro j ec t  
Leader 
Assoc ia te  Xar ine .B io log i s t  
Stenographer I1 
Seasonal  Aid 
Seasonal  Aid 
Seasonal  Aid 
NON-PROJECT PERSONNEL 
Senior  Marine B i o l o g i s t  
Piarine Resources Region 
L ieu tenan t ,  F i sh  and Game b o a t  
"MII1JIBO~~" 
F i s h  and Game Warden 


Diablo Canyon Power Plant site ecological study Quarterly Report No. 2; October 1 - December 31, 1973

http://aquaticcommons.org/215/1/Marine_Resources_Administrative_Report_No._74-3.pdf

Diablo Canyon Power Plant site ecological study Quarterly Report No. 2; October 1 - December 31, 1973

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