I4E'i.
t1Ns.efs1J
FISH
CcttlISSION
OF OREGON
ANNUAL PROGRESS
PROGRESS REPORT
Period Covered:
Covered:
Period
July 1,
1, l96741arch
1967.March 31,
31, 1968
Project Title:
Title:
Prepared by:
by:
Oyster
Oyster 1iorta1ity
Mortality Study
G. Gibson
Gary G.
U.
U. S.
S. Fish and Wildlife Service
Bureau of Commercial
Connercial Fisheries Contract: 14.17-0001-1739
14-17-0001-1739 Contract:
March 1969
TABLE
OF CONTENTS
CONTENTS TABLE OF
Page No,
Pase
No.
INTRODUCTION.
INTRODUCT
ION.
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•. ,•
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METHODS AND hATERLALS .
I4ETHODSANDliATERIALS
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a
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Descriptionof stations,......
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·
Descrietion of stations
Shell growth.
growth.
•
index •
Condition index
•
•
•
Histolosical
samples.
Histological samples.
•
Hydrographicdata.
Hydrographic
data •
a.. a
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RESULTS
RESULTS.
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ltortality
Mortalitx
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APPENDIX.
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11. 1
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M.iARY •
SUMkI.ARY
4
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Yaguina
Yaguins Bay
BSI •. .• .• .• .
•.
Coos
Coos and
and Tillainook
Tillamook bays
baxs . . . .• . .
Shell growth.
srowth.
*
.
•.
•. .
Y
aguina
Bay
*
Yagulna BaX .•
•
Coos_and
Tillainook bays
Coos
and Tillamook
baxs
.
•a
Condition index
index
•a a
•a
Yaquina Bay
Bay •. .• .• . . . . . . . . .
Tillamook and
and Coos
Coos bays
ba;fs • a• . •,
Tillainook
•
Histological samples.
Histolosical
s~les. •.
.
Hydrographicdata.
Hxdrograehic data
• a • a......
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•
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t
7
7
8
LIST OF
OF TABLES
TABLES Table No.
No. Page No.
No.
1.
Mean condition
condition index
index for
for native
native and
and Pacific
Pacific oysters
oysters in
in
1. Mean
Yaquina Bay
Bay and
and for
for Pacific
Pacific oy8ters
oysters inin Tillaniook
Tillamook and
and
Yaquina
Coos bays,
bays, July
July 1967
1967 to
to March
March l968.....................
1968.....................
66
LIST OF FIGURES
FIGURES
Page No.
No.
Page
Fisure No. 1. Yaquina Bay,
Oregon, showing location of
1.
Bay, Oreson,
of the oyster
mortality
stations.....................................
mortality
stations...
. . . . . . . * . . . a . . . . . a .. . * . . . . . e0 . . . .
2
2
LIST OF APPENDIX TABLES
Appendix Table Page
Pase No.
No.
A.
A. Salinities (o/oo)
(0/00) from Yaquina Bay,
Bay. December 19871967­
March 1968
1968 (values
(values at
at high
high tide
tide unless
unless noted)..........
noted)..........
9
9
Temperatures (F)
(F) from
from Yaquina
Yaquina Bay,
Bay, December
December 19671967­
Temperatures
March 1968
1968 (values
(values at
at high
high tide
tide unless
unless noted)..........
noted)..........
10
10
C.
Dissolved oxygen
oxygen (ppm
(ppm at
at tray
tray level)
level) from
fromYaquina
Bay,
Yaquina Bay,
C. Dissolved
(values at
at high tide
tide unless
unless
December 1967-March 1968
1968 (values
noted).................................................
noted)
. . . * . . . . . . * . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . * . . . . .
11
11
D.
(ft) from Yaquina
Bay, December
B. Secchi disc readings
readings (ft)
Yaquina Bay,
1967-March 1988
1968 (values
(values at
at high
high tide
tide unless
unless noted).....
noted).....
11
11
B. B.
E. Hydrogen ion
ion (pH)
(pH) values
values from
from Yaquina Bay,
Bay, December
December
E.
1967-March 1988
1968 (values
(values at
at high
high tide
tide unless
unless noted).....
noted).....
F.
Surface temperatures
temperatures and
and salinities
salinities from
from the
the Tillamook F. Surface
and
and Coos
Coos Bay
Bay stations,
stations, December
December 1967-March 1968 (values
(values
at
at law
low tide)...........................................
tide)...........................................
12
12
12 12
Annual Progress Report
Oyster Mortality Study
INTRODUCTION
Objectives of Oregonls
Oregon's Oyster Hortality
Mortality Study from July 1,
1, 1967­
19671968, were:
were:
March 31, 1968,
(1)
(1) to
to monitor
monitor oyster mortalities to detect aa
possible increase in mortality rate,
rate, (2)
(2) to collect hydrographic data
comparison with data
data from
from areas
areas where
where high
high oyster
oyster mortalities
mortalities occur,
occur,
for comparison
and
and (3)
(3) to
to furnish
furnish oysters
oysters from
from aa relatively
relatively mortality-free
mortality-free area
area to
to
the University of Washington for
for histological
histological examination
examination and
and comcom­
parison to
to oysters from
from high-mortality
high-mortality areas.
areas.
METHODS
M!THODS AND NATERIALS
MATERIALS
Description of stations
stations
Mortality and hydrographic data were collected at six
six subtidal
subtidal
stations in
in Yaquina Bay
Bay (Figure
(Figure 1),
1), aa laboratory
laboratory station,
station, and
and at
at
stations
intertidal stations
stations in
in Coos
Coos and
and Tillaznook
Tillamook bays.
bays.
intertidal
Equal numbers
numbers of
of oysters
oysters
Equal
were retained
retained in
in aa sacrifice
sacrifice and
and aa control
control tray
tray at
at each
each station.
station.
were
The
Yaquina stations
stations each
each initially
initially contained in
in total
total 200
200 Pacific
Pacific oysters
(Crassostrea &igas)
and400
400native
nativeoysters
oysters (Ostrea
(Ostrea lurida).
lurida).
g) and
stations were checked every
every other
other week
week for
for mortality.
mortality.
Yaquina
Yaquina
Four native
and three Pacific oysters were collected monthly from the sacrifice
tray at each station for condition index determination and prepara­
preparation for histological examination.
examination.
tion
The laboratory station contained
100 Pacific and 100 native oysters which were checked daily for
mortalities.
No samples
samples were
were taken
taken from
from this
this station.
station.
No
In December
1967
1967 all
all oysters
oysters at the Yaquina
Yaqutna Bay stations were replaced
repLaced with
younger animals.
animals.
younger
In November 1967
In
1967 a tray containing 500 native
A
station.!1
A = Nonfloating station.!/
B
station, tray
tray
B = Floating station,
C = Floating station,
station, tray
C
station.1/
D
Nonfloating station.ll
0 = Nortfloating
E
station, tray
E = Floating station,
= Floating station, tray
F
F =
C
G = Laboratory station.
station. !/11
-
depth
depth
depth
depth
depth
depth
depth
3'.
3'.
3'.
3'.
5'. 5'.
15'. 15'.
Tray at
at approximately
approximately -5'
-5' tidal level.
level, Pacific Ocean F
~
0
o
I
t
I
%
l
Scale in miles
1
I
IOD
Co
Figure 1.
1. Yaquina Bay,
Bay, Oregon,
Oregon, showing
location of
of the oyster mortality
stations
3.
3. oysters of the 1967
1967 set was suspended
suspended at a depth of 4 feet at Station
C.
C.
These oysters were checked monthly for
for mortalities and shell
shell growth.
Stations at Coos and
and Tillantook
Tillamook beys
100 bays each
each began with 100
Pacific oysters.
samples included
included three
three oysters
oysters from
fram the
the Monthly samples
sacrifice tray and four oysters from
from the
the surrounding
surrounding beds.
beds. Shell growth
rowth
product of
of shell
shell length
lengthtimes
timeswidth
widthwas
wasused
usedf for
de­
The mean
mean product
or de-.
termining growth of Pacific oysters.
oysters.
Native oyster growth
growth was calcal­
from mean
mean shell
shell length
length only.
only.
culated from
During the first 6 months of
this reporting period aa random sample of Pacific and native oysters
- was measured monthly from the control tray at each
each station.
station.
In
order to obtain more
more accurate growth data,
data, all control tray oysters
at the
the end
end of
of each
each quarter.
quarter.
are now measured at
Condition index
index Condition
Condition index
index is obtained by
by the
the formula:
formula: C.l. = drx
CI.
dry weight of oyster tissue
volume of shell cavity
x 100
100
X
by drying
drying the
the oyster
oyster meat in
in an
an oven
oven
The dry weights were obtained by
at 90
90 C
for 11 week.
week.
at
C for
vater displacement method was used to obtain
The water
the shell cavity volumes.
Histological samples
samples
Nistological
Oyster samples collected monthly at Yaquina,
Yaquina, Coos, and Tillamook
bays,
(Hgapersll) were
bays, and dying oysters (flgaperst)
were fixed
fixed in
in Davidson1s
Davidsonts solution
solution
analysis.
and sent to the University of Washington for histological analysis.
Hydrographic data
data
Rydrographic
Salinity, temperature,
temperature, pH,
pH, dissolved oxygen,
oxygen, and turbidity
turbidity inin­
Salinity,
formation were collected twice monthly at all Yaquina Bay stations
4.
4. (Appendix Tables A-E)!'.
A-E}!'.
Continuous temperature
temperature data
data were obtained
obtained
on the commercial oyster beds (Station D)
D) in Yaquina Bay with a Ryan
recording thermometer.
thermometer.
the Coos and
and Tillamook
Tillamook Bay
Bay stations,
stations,
At the
surface temperatures
temperatures and ea1inities
low
surface
salinities were obtained monthly at
at low
tide (Appendix
(Appendix Table
Table F).
F).
R.ESULTS
RESULTS
Mortality
Yaguina Bay.
Bay.
Bay:
Bay:
Pacific oyster mortality was very
very low in Yaquina
Yaquina
0.8\
July-September 1967;
1967; 0.4%
0.4% in
in October-November
October-November 1967;
1967;
0.8% during July-September
and 0.3% during February-March
February-March 1968.
1968.
Native oyster
oyster mortality in
in the
the
same periods was 3.5%,
1%, and
and 5.1%.
5.1%.
3.5%, 1%,
Mortality was
was not
not recorded
recorded in
in
Yaquina Bay in December 1967-January 1968,
1968, because of the initially
high handling mortality in the young replacement oysters.
oysters. Mortality
of native oysters of the 1967
1967 set
1967-harch 1968,
1968,
set was 8.2% in November 1967-March
which Is
is a lower
lower than expected
expected mortality for
for oysters of this
this age.
age.
and Tillamook
Tillamook bays.
bays.
Coos and
Mortality was low
low in
in both
both bays.
bays.
Meaningful mortality percentages
percentages cannot
cannot be
be reported
reported due
due to
to the
the small
small
size of
(100 Pacific
Pacific oysters
oysters In
in each
each bay),
bay),
of the experimental populations (100
occurred.
but mass mortality would have been detected had it occurred.
Shell growth
growth
Yaguina Bay.
Bay.
Mean shell
shell size
size of
of Pacific
Pacific oysters
oysters in
in trays
trays increased
increased
24% from July 1967 through September 1967 and 6.4% during the 2-month
period October-November.
October-November.
Shell growth averaged 16.1% from January 1966
1968
through March 1968 after replacement of oysters in trays with younger
!'
1/
Hydrographic data for June 1966-November 1967
1967 was reported in
in
IIHydrographic Data
II Fish
"Hydrographic
Data for
for Yaquina,
Yaquina, Coos,
Coos, and Tillamook Days,
Bays,"
Fish
C. Dale Snow and
Commission of Oregon mimeographed report,
report, 1967.
1967. C.
and
Gary C.
G. Gibson,
Gibson.
s. 5.
animals.
The best growth in this period was recorded at Station DD
(38.6~).
(38.67.).
Native oyster growth was negligible during July-November
1967
the experimental
experimental animals.
animals.
1967 due to the maturity
maturity of the
Shell growth
also negligible for
for the
the younger replacement
replacement native oysters
oysters
was also
during January-March 1968.
1968.
bays.
Coos and
and Tillaznook
Tillamook bals.
Shell growth was slow
slow during
during JulyJuly­
December 1967
1967 in
in Coos Bay
Bay (16%)
(16\) and
and at
at the
the Tillamook Bay
Bay station
station (10%)
(10%)
December
oysters.
due to the mature size of the experimental oysters.
Growth was
was not
not
Growth
monitored after
after December
December 1967.
1967.
monitored
Condition index
index
Yaguina
Bal.
Yaqaina Bay.
Pacific oyster mean condition
condition index
index (Table
(Table 1)
1)
remained fairly
fairly high in July-August 1967,
1967, but dropped slightly
during September-November
September-November because
because some
some oysters
oysters had
had partially
partially spawned.
spawned.
Native oyster condition was low during July-September 1967,
1967, due to
spawning,
!tfatness" by
spawning, but most
most native oysters had regained their "fatness"
October.
October.
Condition indexes for the young Pacific and native oysters
which replaced
replaced the
the mature oysters
oysters in
in the
the experimental
experimental trays
trays were
were low
low
during January~March
January-March 1968
1968 as
as is
is expected
expected for
for immature
imature oysters.
during
oysters.
Tillamook and
~~
bals.
Coos bays.
mean condition index
Pacific oyster mean
remained at a constant level during the entire study
study period at the
the
Tillamook station.
station.
Tillamook
Coos Bay oysters were variable in
in "fatness,"
"fatness,!t
but generally exhibited
exhibited lower
lower condition
condition indexes
indexes than
than oysters
oysters in
in
but
Yaquina and
and Tillamook
Tillamook bays.
bays.
Histological samples
Samples
Ninety-six native and 137 Pacific oysters
oysters were prepared during
the
the study
study period
period and
and sent
sent to
to the University of
of Washington for
for
histological examination.
examination.
6.
6.
Table 1.
1. Mean condition
condition index
index for native and
and Pacific oysters
in Yaquina :8ay
in
Bay and for
for Pacific oysters in Tillamook
Coos bays,
bays, July
July 1967
and Coos
1967 to March 1968
Yaguina Bay
Yaguina
:8al
Native
Pacific
Native
l<ionth
Month
July 1967
1967
August
September
September
October
November
December
January 1968
1968
February
1-larch
harch
9.3
9.3
9.6
9.6
10.2
10.2
18.5
15.0
15.0
16.8
16.8
16.8
168
15.5
14.6
13.9
13.9
-
-
11.9
11.9
10.1
9.3
9.3
7.2
10.0
10.2
Coos :8al
Bal_ Tillamook
Tillamook Bay
Bal
1/
Pacific 1/
Pacific 1/
1/
-
-
-
12.0
12.0
7.6
11.2
13.2
13.2
14.4
15.7
15.7
-
12.9
12.6
12.B
14.2
10.7
8.9
9.4
-
1/
!I
Includes oysters
oysters from
fram tray
tray and
and surrounding
surrounding beds.
beds.
Includes
Itydrographic
Hldroaraphic data
Hydrographic
from Yaquina Bay
Bay
}Lydrographic information
information (appendix
(Appendix Tables
Tables A-E)
A-E) from
reveals
reveals expected
expected seasonal
seasonal patterns.
patterns.
The area
area changes
changes from
from an
an essentially
essentially
salt-water bay in the summer to an area heavily influenced by fresh
fresh
water in the winter,
winter, with layering
layering of fresh water over salt
salt water
common during
during the
the rainy
rainy season.
season.
Temperatures were uniformly
uniformly low
low
throughout the
the study
study area
area during
during the
the winter (49
(49 FF average)
average) and
and at
at
throughout
the lower
lower bay station
station (F)
(F) in
in the
the summer
summer (55
(55 FF average);
average); while temtem­
the
peratures near
near 70
70 FF were
were common
common at
at the
the upper
upper bay
bay stations
stations (A
(A and
and B)
B)
peratures
during the summer.
summer.
Average daily
daily high
high temperatures
temperatures near
near bottom
bottom
Average
within the
the commercial
commercial oyster
oyster grounds
grounds (Station
(Station D)
D) ranged
ranged from
from 68
68 FF
in July-August 1967
1967 to
to 48
48 FF in
in January-February
January-February 1968.
1968.
Average daily
low temperatures
temperatures during
during the
the same
same periods
periods were
were 54
54 FF and
and 48
48 F.
F.
low
Dis­
Dis-
solved
throughout the
the study
study
solved oxygen concentrations were generally high throughout
area.
area.
Values at
at high
high tide
tide ranged
ranged from
from 5.2
5.2 ppm
ppm in
in August
August at
at Station
Station AA
Values
to 10.3
in January
January at
at Station
Station C.
C.
10.3 ppm in
Secchi disc readings ranged from
from
7.
7.
1.5 feet
feet at
at Station A
A (heavily
(heavily influenced by
by fresh
fresh water)
water) to 7.5
7.5 feet
feet
at Station P
F (nearest
(nearest the
the ocean).
ocean).
Hydrogen ion
ion (ph)
(pH) concentrations
coneentrations
Hydrogen
averaged slightly under 8 at Station A,
A, and slightly over 8 at
Station
F.
Station F.
Pacific and native oysters
oysters were
were retained
retained in
in !lcontrol
"controll! and °sacrifice"
"sacrifice"
trays
subtidal stations in Yaquina Bay and at single intertidal
trays at six subtidal
stations in
in Coos and
and Tillamook
Tillamook bays.
bays.
stations
In addition a group of each
species was retained at
at the
the laboratory.
laboratory.
Observed mortality continued at a low level
level in Oregon from
July 1, 1967-March
1967-March 31, 1968, as
as indicated
indicated by the
the samples.
samples.
Pacific
oyster mortality
mortality in Yaquina
Yaquina Bay was
was less than 1% by quarterly period,
period,
while native
native oyster
oyster mortality averaged
averaged 3.2%
3.2% quarterly.
quarterly.
Pacific
bays.
Pacific oysters was
was also
also low in Tillamook and Coos bays.
Mortality of
Expected
seasonal
shell growth,
index and
and hydrographic
seasonal patterns of
of shell
growth, condition index
data were recorded
recorded in
in Yaquina,
Yaquina, Tillamook, and Coos bays.
bays.
data
"
u.
U.
APPENDIX 9.
9.
Table
Table A.
A. Salinities (o/oo)
(o/oe) from Yaquina Bay,
1967­
Bay, December 1967March
1iarch 1968
1968 (values
(values at
at high
high tide
tide unless
unless noted)
noted)
Date
A
B
B
C
C
Station
D
D
Seaward
E
E
F
12-19-67
13.6
14.9
22.0
22.0
14.6
15.7
15.7
21.4
21.4
17
.1
17.1
25.1
29.4
18.8
18.8
22.6
22.6
31.1
26.3
26.3
31.2
31.4
27.8
27.8
31.6
31.6
32.0
32.0
1-4-68
7.6
7.6
17
17.8
.8
20.4
20.4
14.0
22.6
23.8
16.1
24.3
24.3
25.9
18.3
18.3
28.4
28.4
29.0
19.7
19.7
29.0
29.8
298
25.4
25.4
29.9
29.9
7.2
7.2
13.6
20.4
6.4
6.4
1B.2
18.2
25.6
25.6
19.2
19.2
21.4
26.3
26.3
20.1
20.1
23.3
23.3
28.4
28.4
3.3
3.2
3.3
3.3
2.8
2.8
2.8
2.8
2.8
2.8
3.9
4.7
4.7
4.8
8.5
9.7
9.7
9.9
5.4
6.4
28.0
7.9
7.9
20.4
4.7
4.7
5.5
22.5
22.5
10.6
10.6
14.1
14.1
22.0
18.6
20.1
20.1
23.5
23.5
16.7
16.7
21.7
21.7
24.7
24.7
10.7
10.7
25.5
26.1
19.7
19.7
21.4
21.7
21.7
20.5
20.5
22.4
22.4
22.5
20.6
23.0
23.3
23.3
242
24.2
268
26.8
27.3
27.3
27.6
27.6
27.7
27.7
28.2
28.2
28.2
1-18-68
1-18-68
-
-
2-5.. 6a!1
2-5-681/
0.7
0.7
1.2
1.2
2-26-68
3-14..68
3-14-68
3.4
3.4
-
27.2
Readings at low tide during heavy runoff.
1/
1.1
t
Surface
Surface
Mid-depth
l4id-depth
Bottom
10.
10.
Table B.
(F) from
fram Yaquina Bay~
1967­
Bay, December 1967B. Temperatures (F)
March 1968
(values
at
high
tide
unless
noted)
1968
Date
12-19-67
1-4-68
1-18-68
3-14-68
44
45
45
47
47
48
47
47
47
47
48
48
47
47
49
49
49
49
47
47
48
48
48
48
48
48
49
49
49
48
43
43
44
44
4S
45
44
46
47
47
48
48
48
47
47
48
48
-
48
-
2-26-68
E
43
43
44
45
49
49
49
49
Seaward
F
F
B
-
2-5-68Y1
2-5-6sl
Station D
D
C
C
A
48
48
49
49
-
49
49
49
48
49
49
49
49
48
48
48
48
48
49
48
48
48
48
48
48
48
48
48
48
48
48
48
49
49
49
54
53
53
53
53
53
53
53
53
53
53
53
53
53
53
54
54
53
53
54
54
54
51
51
51
51
51
51
51
51
51
51
51
51
51
51
50
50
50
50
50
50
50
50
50
50
50
50
48
48
47
47
47
47
48
53
53
53
53
53
53
53
53
54
54
51
51
51
51
51
51
48
50
low tide
tide during
during heavy
heavy runoff.
runoff.
Readings at
at low
1/
1:.1
~
11.
11.
Table
Table C.
C. Dissolved oxygen (ppm
(ppm at tray level)
level) from Yaquina
Yaquina
(values at
at high tide
tide
Bay,
1968 (values
Bay, December 1967-March
196741arch 1968
unless noted)
noted)
unless
Date
Station D
D
A
A
B
C
C
12-19-67
9.2
9.9
9.7
9.7
1-4-68
8.4
8.6
8.6
8.8
10.2
10.3
1-18-68
-
Seaward
E
B
F
8.8
8.8
8.9
8.8
8.6
8.6
8.6
8.6
8.6
-
9.6
9.6
9.6
2_5_6811
2-5-68!.!
10.2
lO.2
10.2
lO.2
10.0
10.2
9.9
9.9
9.4
2-26-68
9.0
9.6
9.4
8.9
9.0
9.0
9.2
3-14-68
8.3
8.6
8.5
8.6
8.8
8.8
9.0
1/
11
>
at low tide during heavy runoff.
Readings at
runoff.
Table
Table D.
D. Secchi disc readings (ft)
from Yaquina Bay,
Bay,
(ft) from
(values at
at high tide
December l967-1arch
1967-March 1968 (values
unless noted)
noted)
unless
Date
Stations D
D
Seaward
A
B
C
C
12-19-67
6.0
6.0
6.0
6.0
6.5
5.0
6.0
6.0
1-4-68
7.0
7.0
6.0
6.5
7.5
7.5
7.5
7.5
-
3.0
3.0
3.5
-
4.0
4.5
4.5
2_5_68!"
2-5-6s!1
1.5
1.5
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2-26-68
3.0
3.5
4.5
4.5
5.0
5.0
5.0
4.0
4.0
3-14-68
3.5
3.5
3.5
3.5
3.5
3.5
3.5
1-18-68
1-18-68
1/
11
Readings at low tide during heavy runoff.
runoff.
E
B
F
)
12.
12.
ion (pH)
(pH) values
values from Yaquina Bay,
Table B.
E. Hydrogen ion
Table
December 1967-March
1967-March 1968
1968 (values at high tide
unless noted)
noted)
Station Date Seaward
A
C
C
F
F
12-19-67
7.4
7,4
8.0
7.8
8.3
8.3
8.3
1.4-68
1-4-68
7.3
8.1
8,1.
7.9
8.2
8.2
8.3
8.3
-
7.2
8.3
8.3
8.3
8.4
2_5_681'
2-5-6a!1
6.6
6.6
6.7
6.9
7.0
8.4
2-26-68
7.0
7.0
8.2
7.5
8.2
7.6
8.4
3-14-68
8.0
8.1
8.0
8.1
8.2
8.2
8.2
1-18-68
1/
11
-
t
Surface
Bottom
Readings at
runoff.
at low tide during heavy runoff.
Table F.
F.
Table
Surface temperatures
temperatures and salinities
salinities from
from the
the
Tillamook and
and Coos
Coos Bay
Day stations,
stations, December
December 19671967­
March 1968
1968 (values
(values at
at low
low tide)
tide)
March
Tillamook Bay
Bal: !/
!7
Tillamook
Temperature
Salinity
Honth
Month
BayJ
Coos Bax
1.1
Salinity
Temperature
F
0/00
F
0/00
December 1967
52
52
14.1
51
51
10.8
18.8
January 1968
1968
52
19.2
50
50
10.6
February
Febriary
51
51
1.6
1.6
51
51
1.&
1.8
-
49
.1.3
.1.3
Harch
March
-
1/
1/
Station located on intertidal
intertidal oyster bed in the southwest section
of the
the bay.
bay.
~I
2/
Station located
located on intertidal
intertidal oyster bed in
in Joe Ney Slough.