Fish Commission of Oregon
Final Report
GNAT CREEK WEIR STUDIES
December 1962
Contract:
Operational Studies 14-17-0001-469
FINAL REPORT
GNAT CREEK WEIR STUDIES
Raymond A. Willis
Fish Cammission of Cs egern
Research Division
Class .S Oregon
Decxxiber 1962
FUnds Supplied by the
United States Department o the interior
Ash end Wildlife Service
Bureau of Commercial Fisheries
Contracts
Operational Studies 14;4=.4=1,4469
TABLES cr CONTENTS
DITROO1ICTION,
6
v
s
C
ent. .... o ........
..
0
a
t
47
r
0
..
I;
0
ill
A
issauniog a,' STREAM AND rAGILaiLs
2
,
2usLakaLliAstalltsl.
2
5
caat_gitsugaitia
VETHODS OF COLLECTING DATA.
.
RESUISS
a
flAfttifilmi
n
u
...
9
..........
9
10
a
..........
Yall Oh:mock Solmon
,
JUVellilli Siivor Sallon.
..
.
**
,
23
****
*******
riiscalanoccic Specioo,.
..
,
.
.
1
.
SUMMARY AND CONCLUSIONS
.
ACKNO4LEDONENTS
0
<I
0
.0
.
4.
LITERATURE CITED
o
O
7
39
46
a
3
********
n
*
s
13
10
10
A d u l t S i l v e r a l m n
Productivity,
Stoelboad Trout
1.
**
53
0
58
r,8
62
63
LIST OF FIGURES
ILma_bm
Elams.a
1 Gnat Creek and Tributaries
3
2 Gnat Creek Weir at 130 c f e
4
).
Sampling Traps on Dam (180 c.f . s )
4
4.
Partially-Passable cascades Looatod on Gnat Creek 3 Hiles
above Weir.
9
.
4
Firet of 7 Impassable Falls Located 1 Vine above Nanary arm*
4
5.
6.
.....
Impaasable ?ails at NOuth of Unnamed 'Tributary Near US 30
6
iiridgo
7.
Partielly649assable Culvert Located on Nansry Creek.
.
6
8 Screened Section (left center), Dulkhoed (in beakground), and
Trappe (at right)
0
.
Downstream Trap Basket in Raised Position far Draining. .
6
10.
Several Sea-Ann Cutthroat Trout at 8aso of Dam
8
11.
Upstream Adult Trap with Easi17-9pened Gatos, in Lowered
Position.
a
9.
12.
Upstroam Adult Trap in a Raised Penition. a
130
Waterproof %andom Nueber Table for t'appling Downstream
Migrants
L
15.
16.
P
,
6
e
a
O
4
8
Periods of Gearflou at, the Gnat Creek Dam when Juvenile
Salmonids Gould Migrat, 1955m62.
0 0,116199 4O04,
13
A Comparison of Silver Salmon (Adult and Jack) Counts at
Gnat Creek with Grogan Lower Columbia River and Coastal River
Index Counts, 1955.41
27
Relationship of Numbers of Silver Salmon Jacks in One Year to
Adults in tho Following Year at Gnat Creek, October 1956January 1961
29
....
17.
A Scatter Diagram Showing the Relationship Batmen Circull
Counts and Distances from Focus through First Annulus, 1958
(rood
18.
8
............ o isron
The Relationship of Fecundity to Length for Columbia
..
River Silver Salmon Sample, 1961., o
...
33
37
LW CP FIGURES (Cont I d )
L14=1_1124
Zlin-a&
19 Time of Outmigration of Juvenile Silver Salaam of ths 195.
Brood and Average Daily Discharge, by 5-V Poriods, Oast
Creek Weir, 1959-60.
42
20. A Oaripariace of Points on rito Length...Frequency attributions
with a kraal Distribution (shown as a ntreight lizes).
,
44
21. A-Aarage Lengths and Range in Site of 3,414 Dormstream..14igrant
Silver 531mcci of tbs 1959 Drood at Gnat Crook Weir:, April
1960- June 1961
22.
0
........
Comperieon of LengtbArrequency Distributions of Juvenile
Staelhead Taken by a Sinopling Technique idth the Entire
Population, 1961
47
56
LLST OF TADILS
;able No
1.
Average Flave in Cubic Feet Per Seoond by 5-Day Periodos Gnat
Crook, January 19% -June 30, 1962.
ii.
2. Flom Over the Dam by Day During the Hafts of April and 3%74
1957..62
3.
Comparison of Annual Escapements of Adult Fall Chinook and
Resulting Outtigration of llild Juveniles at (bat Creak Weir,
1955.62......
40
14
.............. .
.
.
.
.
.
17
Catohoe of Fall Chinook Salmon rry and Flow Over Gnat Croak
Woir and Dam by 5..Day Periods, January 16.1April 25, 1961
18
5.
Summary of Chinook Salmon nIrking Lnperimenta at Gnat Creek.
19
6.
Length-Frequency. Distribution of 1956..Drood Adult Fall Chinook
Marked. D.421 that Returned to Gnat Creek in 1958..60
22
Time of Iteration for Mature Silver Salmon at Gnat Creek by
5-Day Periods, 1955-62 p O
24
Total Silver Salmon Cants and Sax Compoaition of Returning
Runs to Gnat, Spring, 'Inter, and liadflell Creek
30
9.
Summary of narkircE4erimenta for Silver Salmon at Gnat Creek
3/.
10.
Summary of Recovery Data far Silver Salmon Ibrking Experiments
7.
......
8,
at Gest Creek ........
11,
12.
13.
14.
15.
.......
a
35
Computations for Deriving the Potential Egg Depoaltion for
Silver Salmon at Gnat Creek from 1955-61 Runa
3a
Counts of Wild juvenila Silver Salmon Migrants at Gnat Creek
Weir by 5. .Day Periods from November 16 to End of Migration
Year, 1954..59 Brood Years
9
40
Charatteristios of the iengtho.Frequenay Distributions in 5-mm
Groups of Wild Silver Salmon Smolts that Migrated out of Gnat
Creek by Brood Year Batmen NoveHher 15, 1956 and June 30,
1961 ..
43
Length..Frequency Distribution of 2.212 1959-arood Yoarling
Silver Salmon, Gnat Creek, May
45
Average Length-WeiOrlt Measurenants for Yearling Silver Salmon
per tall ineter of Fork Length, 1960 Brood. .
o
48
Average Condition Factors for Yearling Silver Salmon per
Millizeter of Fork Length, 1960 Brood. ..
49
4
oalle 6
16.
LIST OP TABLES (Canted)
74UL-ilk
17.
2112La 12*
Comparieone or Annual Adult Silver Salmon Runa and Resulting
Procany at Gnat Creek, 195559 Brood rears.
.
3 OOOOO
50
Sarvival Rates of Silver Sea= Based on Calculated Egg Deposi
Re
Justtnilemiligrant Counts, and Resultant Adults
to Gnat Creek Weir, 1955.60 Brood Years
o
19. A Cam:orison of Coluebia River 0111.0 t Catches and Gnat Creek
Adults with Runoff Index Two roars Earlier, .
0
OOOOO
20.
210
22.
23.
52
54
Auabarg of Adult Steelhead Counted at Gnat Creek Ueir During
Upetrean Micration and Survival. after Spauning4 1955.42 0
0
54
Ilumbare of Wild Juvenile Steelboad Out migrants Trapped at
Gnat Creek Weir, January 1. 1956.June 25, 19620
0
a
a
55
Summary of Information Relating to Steelhead Mbrk Experiments
at Gnat Creek, Through Ttms 1962.
a a
aa
a
0
57
Mievellansous Spooies of Flail Enumerated at Gnat Creek Weir*
Ootober 1, 1955 .June 30, 1962
59
OOOOOOO Bei 4, a
LIST OF APPr',711)11 TAEILS
I.
110
Ill.
Length...Frequency Tabulation of narked and Unmarked Will Silver
Salmon Adulta at Gnat Creek, 1956.57. .
c
I
65
Longt.hp-Preqpency Tabulation of Marked and ihmarked Wild Silvar
Salmon at Gnat Creek, 1957.58
.
.
0
0
.
66
Length-Prequency Tabulation of Harked and Inmerked Wild Silvar
Salmon Adults at Gnat Creek. 195.59.
67
N. Length.Freguenny Zahulation of Morload and Varna:re, Wild Silver
Salmon AdUlta at Gnat Creek, 1959-60...00,,
V.
VI.
Length.Fregnenoy Tabulation of thriced and Inmarkrd Wild Silver
Salmon Adults at Gnat Creek, 196061. OOOOO a o a
4)
00
68
69
Length-Pregnancy Tabulation of lUrInd and Unmarked Wild Silver
.
Salmon Adults at Gnat Creek, 1961.6200
VII.
0
a
langth.iiireguency Distribution of Adult Fall Chinook Salmon in
the 1960 Run at Gnat Creek Whir by Sex and Mark
0 4 0
.00.
70
71
ABSTRACT
Gnat Creek heir, constructed with federal funds& wa3 ocmploted in
October 1955. Primary objectives udre to quantitatively study fail chinook and silver salmon to: (1) determine tho aurvival& Mating& and else
of juvenile salmonids resulting from natural epawning; (2) measure the ourviva' of hatchery eared fingerlinge and yearlings; (3) deterrine if a relationship between varying stream flows and adult production existed; and
(4) study the juvenile production resulting from various numbers of adults
above the weir. The source of Gnat Creek is at 2000 feet altitude and
the stream aystem drains 22 square miles. Palls itd other obstructions
limit th3 production urea above the weir to the central part of the rain
stream and parts of tiro snail tributaries. Counts of juveniles& although
not complete des to spill over the dam above 150 cae.s,& are concidered
accurate and complete during times of no spill. Survival rates for silver
salmon molts (yearlings) were O*5 and 2,0c:, of the naximun calculated egg
deposition in the two years with no spill during April and Hay and averaged
1.5% for all years. Seventy -one per cent of the anolts migrated during May
and 90% taring April and Hay. The averace size of 7,878 amolta from 6 brood
years was 114,9 mm fork langth with 95% confidence limits or 874142.0 um.
Silver salmon survival rates of adults ealy (jacks excluded) returning to
the weir averaged 2.5% of the colts counted downstream. An excellent caza
relation ezisted between the numbers of silver salmon jacks in ove year and
the nurribars of adults in the follouina yeas at Gnat Creek, Counts of stem.
head adults and juveniles are presented and a nanusaript concerning a teat
of spaghetti and Petersen toga on eteelbead was pevared.
rimoDucTrm
Flo Si
Ferns
As a part of the Coluebia '.laver Fishery Development Program (CRFDP) be.
tweet the Oregon Fieh Commiseion (OPC) and U.S. Fish and Wildlife Service
(U3713) 2i/ it mas desired to learn nee° about the fresh-water phase of areeiro.
sous selmonid life history in general, and lower Colembla River fall chinook
salmon in particulars
After numerous etraam survyt had been conducted on Oregon tributaries
below the allamette River, it was apparent that only ono or possibly two
streams would be at all suitable for a two-kray weir on a stream having an
appreciable minimum floe.
Onat Creek vas chosen when prelieinary engineoeing
and biological data indicated maximese flows mould net likely eeeeed 4000 c.f.s
and mieleum flows would be about 10 c.f.s.
Two species of selmon, ehinook
Qb1101141=112111604dWaNO and siIver (O. =AO) or who, more present in
addition to steelbead (alsgamarliaajd and seserun cutthroat trout (1alla
03,e0i).
Construction ens completed in 1955.
The Gnat Creek project mns initiated prior to the publication of tvo
extensive papers dealing with weir studies on silver salmna and steelhead
(Salo and Bayliff, 1951, and Shapavalov and Taft:. l954)
,,
WW1=
Objectives of the study were:
(1) determine tho Bum-teal, tieing, and
size of juvenile salute -aids resulting from natural spawning; (2) measure ehe
survival of hatcheryereared fingerlings and yearlings liberated into Gnat
Creek; (3) determine if a relationship between earying stream flows a
adult
production existed; and (4) study the juvenile production resulting from various nuriners of adults above the weir.
Although uncounted numbers of juveniles
Later the Bureau of Comnercial Fisheries of the MM.
2.
Tmuld migrate over the dan when floes exceeded 150 cer.s., it was hoped that
a sampling technique =did be developed for obtaining a reliable estimate of
those fish that by-Teased the counting facilities.
gaged screens later caused water in
excess
Corrosion of the heavy-
of about 135 c.f.e. to spill over
the dam and the use of suitable gear for sampling on the crest of the dem dure
it g sterns, especially at night, was cely partially solved by Juno /962 uhen
the field project terminated.
DF.SCIIM ION C2 STI1EAll AIM FACILITIES
aMtegraitik=4191
The Gnat Creek system is in Clateop County, Oregon:, and drains the northern
ulopes of Nicolai Mountain in the Coast Range.
it originates at en altitude
of 2,500 feet and flows northerly into Blind Slough which joins the Columbia
River 2S miles above its mouth (Figure 1) .
Climate of the 22-square-mile
&tee= system is generally sievilar to that of other coastal foothill areas
eith abundant rainfall in the fall, winter, and spring =the. A maximum flow
of 1,300 cello° occurred at the weir for a short duration an Movember 22, 19592
as a result of 3.8 inches of rain in 12 hours.
Minimum flows, on the other
bland, of 7 cef.s. were often encountare in the meneee after a prolonged perie
od of dry weather*
The mouth of Gnat Creek at high water of the CoIudbla River is located
approximately between Supply Creek and Rock Creek.
The uelr ulth the dua
on the north side (Figure 2) and the careens on the south aide (Figuree 2 and
3) is located 100 yards upstrean from the mouth of Roek Creek.
graphe wore taken on December 11, 1961 ehen the flow
Ma
The photo-
180 c.f.s.
Throe
miles of stream are accessible to enadronous fish betuesn the weir and a
6.8 foot cascade (Figure 4) ehich is located about 100 yards above the U. S.
30 highway bridges At low flows this cascade appears to be impesaable and
3.
1
0
Blind Slough
Mile
WEIR
4
;
rNAT/CREK
u.S.30
Hiptueel
LEGEND
Dam
Culvert with passage problem
Beaver marsh
Falls
El.
2,500 Ft.
Nicolai
Mt.
El. 3,020 Ft.
A
Figure 1.
Gnat Creek and Tributaries.
Figure 4.
Gnat Creek Weir at 180 c.f.s.
PartiallyPassable Cascades Located on
Gnat Creek 3 Miles above Weir.
Figure 2.
Figure 5.
Sampling Traps on Dam (180 c.f.s.).
First of 7 Impassable Falls Located 1 Mile
above Manary Creek.
Figure 3.
)cs
However
usually represents the upstream limit of chiaook salmon mgration.
silver salmon and steolhead trout are able to pass.
The gradient in the 3.mile
section of stream below this cascade is rodorato with several fair riffles
of coarse gravel.
Occasional channel changes with scouring of the stream bottom
have been observed.
A new hatchery operated by the Oregon Game Comnisnion (OGC)
under the federal pros-ram in 1560 at the hilbway -cridge.
is about 400
design.
yards
above the cascades and is equipped with
is constructed
Its water-supply dam
fisheay of rodern
;later for hatchery Imo flows over a heavy.duty: fine-meshed: inclined-
plane sareen.
Occlsional to
flows at the dam present a problem to upstream-
migrating adults such as steelhead in Hay of some years,
The remains of ar old dam are loce:,ed about 3 miles above the hatchery
mater-oupply dam.
This wooden crib dum wan considered to be an impassable
barrier to fish nigratIon during its use in the logging operations
One mile above
ranary
mile over 7 falls.
of 1920.-.30,,
Creek: the stream drops about 800 feet within one-balf
A photograph of the lower most of t.h .s eerier; of falls is
shown in Figure 5.
of
Most of the Gnat Creek tributaries above the weir are roa.producars
Rock
anadronous fish because of impassable bariers. Although the mouth of
imiassable culvert
Creek is below the weir: this steep-graiient stream has an
at moat flows under Kiebuay 30.
Dig Noise Creek has a steep cascade mtich is
D.oeatccl 1/4 mile above the highway and is impassable at most floes.
An un-
30 has an ienamed tributary located opposite the 0;;C Hatchery at Illipuay
eassab/e falls at :Its mouth (photo in Pierre 6).,
/tonere' Creek hue a rend
imraosablo at
culvert (Figure 91 about 1-1/4 miles above its mouth tint is
to past throu gh ita
most times althoun an occasional steclhead is able
priTire No-tfry fill: counting facility: commonly called a mein: was
Figure 8.
.A.orar
%Ala.
'tt.7 -
Impassable Falls at Mouth of Unnamed
Tributary Near U.S. 30 Bridge.
__-.NOMPOOM
Screened Section (left calker), Bulkhead
(in back round), and 'trips (at right).
Figure 6.
ABISIGILigtaiMingrri.114
Figure 9.
Figure 7.
Downstream Trap Basket in Raised Position
for Draining.
Partially-Passable Culvert Located on
Manary Creek.
70
Dozily in tuo parts, viz., the 10D-foot.lona dam 10 feet high, and 9 inclined.
The two parts
plane screens leading to a holding box in a trap (Figure 2).
yore separated by a rook...filled, crib bulkhead running parallel to the stream
upstream about 100 feet to the wooden enter-control structure which allowed a
maximum of 135 c.f.s. to the screened part.
Tuo gates and stop logs con-
trolled the amount of water to the screens and the excess over 135 cof.so teas
diverted over the spillway.
T-.70, additional stop logs (shown in rigure 8)
at the head of each ecreon provided additional eater control depth adjustments
over the screens.
Each of the nine l/8-inch meet, screens passed up to 15 eef0s6
in such a manner that ,17ish of varioun sizes were collected into a continuous
trough under the lower ends of the screensf,
A longitadinal =rem of 1/2-
inch mesh provided a separate section of trough for the smaller fish.
The
%rough carried the 'ieh in water to the downstream trap (ehon in the raised
and drained position in Figure 9).
Erceesivo utter from the trough by-passed
the downstream trap (to prevent turbulence for the fish being held) and fish
When emptying
vere separaaed by a re .aey screen driven by a paddle wheel.
the trap the entrance wae closed, the trap basket with fish and uater was
lifted by an electric lloist and drained by two hoses into two standard hatchery
troughs far inspection of the days catch.
After inspection the fish were
returned to the atream below the unir via r. cira;re elbh unter,,
The upstream trap tins located bates= the downstream trap and the first
inclined -plane screen and utilized the flow from the doenctream screening and
trapping facilities far added attraction to the email ladder and trap entranoeo
Fish occasionally appeared at the base of the dun (shown in Figure 10) but
most soon located
the
ladder leading to the upstream trap.
In 1961p a floate
irk compartment vas installed so the adult fish would be lifted in water a
shown in Figure 11 (lowered position) and Figure 12 (raised popitioa)0
Figure 12.
Figure 10.
d
r
a
f"
Of
Upstrean Adult Trap in a Raised Position.
of Earl.
Several Sea Run Cutthroat Trout at Base
Figure 13.
Figure 11.
Waterproof Random Number Table for San,
piing Downstream Yigrants.
Upstream Adult Trap with Easily- Opened
Gates, in Lowered Position.
.u)
9.
VETHODS or couxual Dx14
Air and water temperatures mere obtained by a Ileksler recording therremoter.
Stream flees Lore obtnined from gage height to flaw conversion
tables prepared by the WC Engineering Division.
An index for each annual
average runoff in inches per acre, siee nee to that deeele2ed in Washington by
Seeker (1953), was calculated by the formulas
Tridcz =
-Web'
wince° k is the yearly total floe in c.f.e.; C is the constant 1e9835 that
converts c.f.s. to acre-feet and converts the numerator to inches; and the
denoninator is the area of the rest Creek watershed Le acres.
Jumenile salmenids were separated by species and individually counted.
all chinook juveniles eore all 0+ emeept where noted,
Silver juvenilea 'ere
tabulated arbitearily ce 0+ thrc.ugh November 15 nid as 1+ yearlings or smelts
from that, date until the end of the folloming eprengc
Tweeyeareold smelts
were identified among the latter group but in ireignificant nembers. Ealebeerateelhead trout are noted as steelhead for the sake of brevity.
Lengths of juvenile fish UGVO recorded in both millimeters ard inches
but are etandardized in this report as fork length in ndllineters.
Lengths
of adults wore recorded to the nearest one-Leaf inch (fork length) and sdiee
sequent3,y rounded to the nearest lower inch in keeping mith length measure-
mente obtained in the commercial fishery. With miner excelptions, no aneebhetice
were used while IlareWmg the fieh. Rand= samples of juvenile silver sale
and steelhead were eollectod ulth the 0.4 of a
mricion nunbers table,
Appropri -
ate information urea put on a water-proof table for reference in cellecting
the sanples (Figure /3).
Emeieations of all silver sal= scales collected mere made with a
Daeech and Lomb Tri-Sleplece projector at 150 X which Ise calibrated with an
100
American Optical stage micrometer.
Circuli mere countod along a 20° line on
either aide of the anterior-posterior axis thru,k_t the and of the fresh-water
Distances mere measured in units of 1/40 ino1- ftsom a Bruning proci
sion ruler from the center of the focus to the /act circulua counted.
RESULTS
Stream flew data were recorded each day tbo troy uas attended; the averages
for 5-day periods from January 1956 through June 1961 are presented in Table 1.
Conversion of runoff into overage depth:, (in inches per acre) have boon cal-
callted for Inter use in studying silver salmon production in relation to flame
Dates associated with possible incomplete counts of juvenile fish durinc
times of spill over the dam ors shown graphically in Figure 14.
Closer examine.
tion of the duration and magnitude of these spills is possible with tho listing of water volumes by day during the major downstrenry-nipation ;varied in
April and Ilay (Table 2).
Voluminous rocorde of stream torrnoratures have boon roearioI but ore not
presented.
aika
Fall Chines SaImon
From inspection of tLe fall chinoo7.1 adult counts in Table 3, it is .c .dilly
apparent that runs aro sporadic in Gnat Creek.
The adult counts to the veir
are quite accurate in centrant to the fry and fingerling outmigrantso
Since
noarV
all of the Gnat Creek fall chineok juveniles migrate down-
stream in the month of February, and reverence to Figure 14 inflieates
considerable
spill in February of each year:, substantial enumeration errors for those fry
are suggested.
Additional error ray have been introduoed into counts of
c120
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12.
Table 1,
Date
Septembmr
1956
1957
5
a
10
15
14
a
7
7
8
9
9
10
10
10
10
20
20
25
30
October
5
10
15
20
25
31
November
5
10
15
20
25
30
December
(Gont3d)
10
9
10
19
10
10
13
71
130
92
93
48
45
145
49
34
10
10
28
159
59
50
25
35
153
258
175
135
31
72
71
107
205
65
294
291
239
40,070
23,200
111.31
67.72
5
10
15
20
Total Runoff
(c.f.e./24 hrq,)
Average Annual Flow
1958
1959
1960
8
30
27
12
42
40
9
9
8
9
10
10
9
8
17
10
56
32
17
26
253
354
338
227
10).
138
113
122
122
188
173
1961
1
8
8
9
9
10
10
8
76
119
61
152
89
69
50
17
12
9
35
80
12
17
9
29
49
44
152
333
411
187
35
31
42
93
43
133
506
126
85
64
162
337
52
93
65
72
7
9
7
55
28
195
109
122
80
71
86
91
57
262
220
180
33,130
48,415
29,360
31,845
64.44
92.03
134.49
81.56
88.46
39.21
56.10
81.82
49.62
53.82
91
.137
(cot's.)
Runoff Index
The last interval of the month is
days in 31-day months.
over the dam are included during times of spill.
Flows
.
12
1
ii
i.
01
R9 Mal CEIN
=wrammu...Ire.wwm
MAE=
:'
1962
1961
1960
1959
1958
1957
Jan
20
Feb.
10
30
10
30
flay
20
10
June
30
20
July
ill M
10
30
Au z.
20
30
20
Sept.
10
10
MO
III
1111
1
1
]
1
20
ii
H
1
*VIVI
MN 111
la
,
1
owl
--1
1 MI IS
IN
Ewe
Sul:maids Could Mi:;rate, 1955-.62.
30
Oct.
20
Periods of Overflow at the Gnat Greek Dan When Juvenile
April
Figure 14.
20
Mar,
.........
11
IIIIIIIIIIIR
10
20
Nov.
30
10
Dee.
30
La...1-11-t--11LI.J.L.A-14-1-.-1-:-La-i-J
..,.s...L...,i.,....1..i..L.L.L.L_W..2...L.1....L.A.A-L-L,A.1_1-Li_i_A_
10
20
30
10
10
20
30
20
10
30
30
Ca
1
MR ''' t MI KO
-
K SO
EEO RI iiiiiiMEEMEM
!4,., fir, t .,.
EMI 1111V: IR
I II II
an
1955
Table 2.
Flows Over the Dam by Day During the Months of
April and Iicayp 1957-620 IV
Calendar
Month Day
1957
April
1
2
3
4
5
6
7
8
9
10
IZ
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
ter
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Flow
78
69
69
110
143
115
Calendar
1957
Month Day
May
18
43
42
38
36
28
25
27
26
26
1960
April
31
23
1
2
3
128
128
0
105
97
86
80
77
0
70
61
70
4
65
58
6
0
7
54
8
9
50
48
47
46
46
44
42
39
38
32
31
31
39
32
31
27
28
29
28
26
26
36
29
32
30
98
90
90
72
65
62
81
156
130
100
100
86
90
0
67
60
aow
5
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
63
95
116
0
0
94
123
106
106
111
111
106
106
109
118
112
88
87
150
Table 2,
Calendar
Month fay
1960
Thy
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
a22
23
24
25
26
27
28
29
30
31
Flow
0
84
75
72
(Contld.)
Calendar
1961
Month Day
April 14
15
16
17
18
19
20
21
22
63
63
0
0
56
57
57
23
24
67
25
26
27
28
29
8?
30
54
55
0
0
106
120
93
101
106
101
106
111
114
95
80
0
0
65
Nay
1
2
91
3
92
99
89
84
77
73
4
5
6
7
8
9
10
11.
12
13
14
i.pril. 1
2
3
4
5
6
7
8
9
10
D.
12
33
106
108
103
89
82
77
72
74
75
66
65
69
76
Flow
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
79
70
58
52
56
67
56
52
47
45
42
40
42
43
40
38
36
36
40
35
3].
16,
Table 20
Calendar
Y_onth Day
Flaw
(Cont'do)
Calendar
Month Day
Flow
44=10111=111....=4.22Z241
1961
1962
May
April
30
31
1
29
28
May
12
13
56
51
14
15
16
17
18
19
48
45
42
5
74
71
67
74
67
6
98
20
21
22
7
106
23
2
3
4
8
9
10
11
12
13
15
16
17
18
19
20
21
Mly
1962
108
108
95
85
78
72
62
98
1
103
92
100
83
74
77
66
6
7
30
34
31
30
51
55
54
30
5
24
25
26
27
28
29
l3
38
39
37
35
36
35
54
54
49
45
45
4
36
43
55
22
23
24
25
26
27
28
29
2
3
40
39
37
51
51
84
81
81
8
9
10
11
57
56
Thn total Gnat Creek flow on a particular day is the stet of the flow
over the dam plus the flaw over the careens, This table shows the magnitude of the flows over the dam during the periods indicated in Figure
lt. I o mdgrntion over the dam was apparent when the spill was less than
c,for,
Table 3.
Comparison of Annual Escapements of Adult Vail Chinook and
Resulting Outmigration of Wild Juveniles at Gnat Creek Weir,
1955-42.
Year of
Parent
_AU&je...atiet..10
Fe
1955
1956
1957
1958
1959
1960
1961
1962
Year of
OutmiC411,
1124. 44 04
o (o)
35 (0)
1 (0)
51 .33)
2
23
3
-
58 (0)
16
--
56
33
4)
2
67 (33)
79 4)
88 0)
6
0)
23
53
3
ant
-
7 (0)
0)
2 (0) 1/
Weir Count of
Resultant
41
_
1956
1957
1958
1959
1960
1961
1962
1,279
432
45
174
0
a
177114.0i.s in parentheses list jacks which are included in the total.
juvenile fall chinook due to occasional fish passing over the rotating screen
during flooding conditions.
in 1960.
A larger and more efficient screen uas installed
The meet successful operation of the 5 scoop traps on the dam was
accomplished in the minter and spring of 1961 and those sampling data are i14.14
eluded in Table 4.
The total weir trap count of the 1960 brood was 174 (in
Table 3) and 164 of these uere caught between January 16 and April 25, 1961.
Since all 5 scoop traps fished 10 lineal feet of the 100.foot dam, a total
of 1,000 1MS estimated to have passed over the dam during that time interval.
No statistical treatment of these data appeared warranted because of the small
numbers involved.
Additional details concerning fall chinodk adult and juve-
nile counting were presented in each annual Gnat Creek progress report fram
the start of the project in 1955 through June 19626
A summary of all past ohlnoOk narking experiments at Gnat Creek including
liberation data and all actual recoveries is presented in Table 5.
50,000 fish are involved in each of 8 experiments.
Less than
The purpose of four of
the experiments ups to compare the returns from fingerling vs. yearling
00008
00.0.
IRPt$
ter
C7%WrsqZ40
uNeftmp..H0
vcd
MV0H0
OAQ
t-g1140
rivAtq00
mNOHO
v00
Nww,400
-striggH0
00000
8
000
vH.0000
n0-4000
00000
.0
000
0HO -400
00t000
00000
ON
(Th
0
4
000
OHNMOO
00M.400
00000 A
N00
0.4N.000
0004"HO
00000
000
OHONN00
HHOm00
00000
R*R
kr.01^011"NcQ
R
11
HHcvNN It%WAFCRg tiN2L4R`07
4
0
Ll.c
oicp4w
.0Pv
Ad
Mark
RP
1955
Ad
Ad
1956
1959
5
Time of
Liberation
Identify
Natural Stock
Identify
Natural Stock
Liberation
Bonneville
Bonneville
Bonneville
Bonneville
to Sandy
Bonneville
W
Gnat Creek
W 1/ Gnat Creek
H
H
H
11
Results of Returne
Time of
Liberation
Time of
Liberation
Origin
of Eggs
3/110/24/57
2-4/60
4/15/38
6/12/57
4/3/57
6/20/56
6/2425/54
7/1/55
tate
45
1,022
24,600
'z6,221
23,938
25,997
494851
49,641
9W
BW
Br,
Dr.
Br.
Br.
Br.
Br.
40 mm on
3/20/57 (F)
11-2" (F)
2.2" or 262 /lb 16,466
at marking (F)
4-5" at
12,264
release (Y)
50
63
88
75
5 days
3 days
2 days
3 days
(Migrated prior to
weir construction)
278/lb at
19,436
marking (F)
3.6" at
21,007
release (Y) 1/
180/lb at
marking (F) 1/
64 mm (F)
Release and Juvenile Recovery
ormation
Number Release
Weir Recovery
Average
Size
Site 1/
gliligi3Sur- Fri Re siviva 1
dense 4/
Summary of Chinook Salmon Marking Experimente at Gnat Creek.
H lj Bonneville
and to Appraise H
To Augment Runs
of Fall Chinook
Marking information
Purpose of
Experiment
1956 D-LM Time of
1956 D-RM
LP
1955
1954 D
1953
Brood
Year
Table
1,1
0
LP
RP
D-Rh
D-LM
Ad
Ad
1954
1955
1955
1956
L956
1956
1959
1
1
2
7/( 21_4 5)
Sport
1
1
(2 3
3
1
4,1
5
4,.)
Comm.
River
(23
t
1
431
Sport
177
1
1
1
1
(2 3 4 5)
Actual
(Continued)
32
36
24
0
0
24
3
0
98
3
6
5
1
0
10
3)
Recoveries
for Rxperiment
2.2
(2 3 4
Creek
lb/
FW Residenoe = NuMber of days that elapsed until 50% of the Enrovivors of a particular group migrated pest the
weir° For exarFas, 50% of the 190436 migrants narked LP were recaptured at the weir within 3 days after
liberation.
Single fin reooveries in the fisheries have little or no significance°
Little White, Spring Creek, and Dig Creek hatcheriee0
2/ !lumbers in paretheses indicate age at recovery°
IJA77:76Eiaery; W = wild,
Br. = released at highway bridge boated 3 miles above weir; SW = below weir°
F =fingerling; Y =yearling*
1.3,1
Ad
Comm.
(2 1 4 3)
1953
Bro
Year
5.
AdultWecovery Informat n
Table
liberations of hatchery fish into Gnat Creek,
The 1955-brood experiments used
tuo nearly-equal groups of fish from the 3onnev-ille Hatchery.
One group ens
marked LP, reared until June 20v 1956, and released when about 2-1/4 inches in
length at the Niehway 30 bridge,
The oecond group, narked RP, wee reared 8
months longer at the hatchery and eas liberated from the came location when
3.6 inches in length.
The same type of experiment uas repeated using 1956
brood; the yearling group (1)-110 uas somewhat larger than the yearling group
(TNP) of the 1955 brood.
d consistency in all four groeps le that ogee
if of
all fish surviving to roach the weir on the outward ndgration wore counted
Within 2 to 5 days of the time they uere liberated.
The reason for the cape
sistency of the rapid movement domnetream immediately after each liberation le
suggested by the remits of Miller4s (1957a and b) studieu with cutthroat
trout in Gorge Creek, Alberta, Canada.
F2 denceetented that native resident
fish had established home territories ubsee they mead eeend their entire
life.
After liberating hatchnryereared fish into the stream and neasuring the
blood lactate levels of both groupe, he found the hatchery n
pe had signi-
ficantle higher mounts of lactic acid and concluded that in competing for
space and food, the introduced group oncomtered higher mortalitieu.
Higher
lactic acid ancunts were also found in the hatchery groups liberated into
areas devoid of resident trout,
Total stream survival of all chinook between
the time of liberation and their migration to the Columbia River varied from
50 to 885 with the lowest fresheeater survive]. from the 1956ebrood yearling
group,
Subsequent actual returns (98) of adult fish, houevery showed the
best marine survival from this geoupc,
nowever only 6 fish from this
experiment were recovered in all of the various fisheries,
Table 6 oantains
length neaseremente of 92 of the 98 tdult chinook salmon that returned to the
Gnat Creek Weir at 2, 33 and 4 years of aee.
covered in the fall of l961n
Ho 5-lemeeeoId chino& were re-
The recoverioc fIrom the other chino& marking
Total
36
37
35
30
31
32
33
34
22
23
24
25
26
27
28
29
15
16
17
18
19
20
21
32
6
7
11
12
13
14
1958
36
1
1
0
0
0
4
6
3
3
3
1
3
3
3
1
24
8
8
92
3
0
1
4
0
1
0
4
4
0
0
0
0
1
0
0
3
0
3
6
3
3
3
8
8
1
4
4
3.
3.
0
6
12
7
......41110
Total.
0
2
1%0
1
0
2
1959
LengthWrequency Di3tributione of 1956.3 rood Adult Fall
Chinook Marked D..42 that Returned to Gnat Creek in 19566600
Fork Length
(in Inaba)
Table 6.
22
230
experiments appear to be toe few in number to uari'ant any further analysis.
Silver Sa lrao.n
Adult Silver Salmon
Table 7 summarizes the timing of adult and jack silver seinen by sex to
the Gnat Creek Weir for each year from the start of the project in October
1955 to its and in June 1962. rem the 7year totels of the counts: it is
apparent that the fish have entered Gnat Creek as early as the third meek in
Septenber and an late as the second meek in Febreery.
Feak jack counts uere
both earlier and later than peal: adult counts: although none of tiro= peaks were
sharp and well defined.
Most of the adult fish were not ripe upon arrival at
the weir prior to November 20 but beeene progressively riper after that date.
From incarnation at spring Greek: s 1e10 cores. rivulet of the Wilson River
of Tillamook BAL7, fenales took about 12 days and males 10 days to .palm and
die after reaching, their
sparring
sites (Willis: 1954)0
The average run at
Gnat Creek was 150 nature silvers compoecd of 32 moles (over 20 :,..nchen in
length), 84 jacks (precocious nales less than 20 inches), and 33 reeales.
per cent this is 22: 56: and 22, respectively.
In
From the cumuletive totals an
average of 375 of all adults and jacks arrived at the usir by Nevenber 20 and
95% arrived prior to January 10.
The emulative totals (In per cent) of
females is just slightly lower for the same tine periods.
All adult fish uero neasured (with miner exceptiona) and Iengthefrequeney
histograms of fish for each run are graphed in previous processed progress
reports (Kruse: 195Wileas and Kruse: 1961; and Praha and Willisk 1962) 0
General consistency of escapement abundance for Oregon tributaries of
the lower Columbia River (601 eles): Oregon coastal streana (Oekley: 1961),
and Gnat Creek counts are shown in Figure 15.
Divergence in 1961 is readily
apparent when both the Gnat Creek counts and lower Columbia River index counts
) Xruee: Thomas Eop 19590
(Typewritten report).
Sumnary of Gnat Creek Weir Operationsp 1958-59
42
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26,
Time of nigration for Ibture Silver Salmon at
Gnat Creek by 5-Diy Periods, 1955-62. (Contra.)
Table 7,
ela-12-41201----
Period
Ending
Cum.
Sept, 15
20
25
30
Oct.
5
10
15
20
25
30
Nov.
5
10
15
20
25
30
Dec.
Jan.
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
1
0
1
0
2
0
5
10
0
15
20
25
30
0
0
0
0
1
0
0
1
1
0
0
2
0
3
15
18
0
5
1
0
0
0
0
0
1
0
0
1
0
0
1
10
18
0
2
0
3
1
1
0
4
26
10
18
0
16
5
13
12
9
26
0
0
19
23
0
0
3
,-.....,
16
17
0
3
1
0
0
2
1
2
0
0
0
0
0
0
0
0
0
1
0
0
0
2
3
0
2
2
2
0
0
6
1
7
8
24
31
5
32
2
53
7
15
18
11
25
42
14
14
4
34
70
114
105
45
70
106
1
7
81
61
24
27
38
21
26
33
36
13
42
29
10
9
2
51
45
50
60
5
1
22
6
0
1
2
4
3
1
2
1
2
0
0
20 9 ..2_2_4
7
2
1
0
4
9
6
1
79
227
588
231
1,046
32
22
94
31
22
149
5
30
5
10
15
2
0
0
0
0
0
0
0
0
0
0
0
8
0
8
3
2
1
0
0
0
0
0
3
0
0
0
0
0
0
0
0
0
0
55
16
7 -Year Average
7.Year Average in Per Cent
5
2
11
1
2
0
Total
0
12
3
25
13
0
2
1
2
20
25
Total
0
3
2
10
15
Feb.
Cuss.
1
6
4
21
33
59
11
13
5
4
Q.0......2_
56
9
16
48
82
152
266
371
416
486
592
643
688
738
798
819
902
961
972
98f
990
994
1,026
1,022
1,026
1,030
1,039
1,045
12046
0.0
002
008
0.9
1,5
4.6
708
14.5
25,4
35.5
39.8
4605
56.6
61.5
65.8
70,6
76.3
78.3
86,3
92.0
93.0
94.3
94.6
95.0
97.1
97.7
98.1
93.5
99,3
99.9
100.0
Cum.
Fermi,
.
-.
2
0
0
7
9
16
31
49
60
85
127
141
155
159
171
174
199
212
212
214
215
217
222
223
225
228
229
23].
0.0
0.0
009
009
0.9
3.0
309
6.9
13.4
21.2
2509
3608
55.0
61,0
67.1
68,8
740
75.3
86.1
91.8
9108
92.6
93,1
93.9
96,1
96,5
97,4
98.7
99,1
100,0
270
Year
Gnat
1955
1956
1957
1958
1959
1960
1961
174
224
30
209
54
22
21
20
17
Coastal Rivers
53
170
103
87
79
60
50
Gnat Creek Weir
Coants
40
Coastal.
Survey/
Index Counts
rf
120
801-
///
Lowar Columbia River
Survey Index Counts
1955
Figur. 15.
1956
1957
1958
1959
1960
1961
Comparison of Silver Salmon (Adult and Jack) Counts at Gnat
Creek with Oregon laver Columbia River and Coastal River Index
Counts, 1955-61.
A
28.
were down while the coaetal river index me up eebstantteIl,y.
A good correla-
tion exists (r = 0.87 with 5 degrees of freedom) between the Gnat Creek counts
and the lower Columbia River spawning ground counts (jacks iaaluded).
Car-
relation coefficients were also camputed for adults only from 1957 through
1961 (lower Columbia Riser survey counts for 1955-56 were not used because
jacks ears not aleayc listed separately). When the abundance of adults is
compared at Gnat Creek with the lower Columbia standard survey units, the correlation coefficient obtained is quite high (r = 0.90) and significant at the
54 level.
The correlation coefficient (0.78) between the Gnat Creek and the
coastal river counts is not significant at the 55; level (r.05 = .878 for 3
degrees of freedom).
The relationnhip between the members of jacks in one year and the numbers
of adults the following year for Gnat Creek is shown in Figure 16,
A very
good correlation (r = 0.922) resulted which is significant at the 55 level
with 44 degrees of freedom°
The percentage sex composition of jacks, adult males, and females in the
silver salmon runs each year at Gnat Creek are compared in Table 8 with sieller
data from Minter Creek (Salo and Beyliff 1958), !laddell Creek (Shapavalov
and Taft, 1954), and Si in Creek Willie, unpub. naftuscript).
The average
percentage of feealos was similar at Gnat (22%) and Spring (25%) creeks but
only half of that for lamtsr (455) and Waddell (44%) creeks.
The proportion
of adult males in the rums at Spring, Minter, and Waddell ereaks wan generally similar but Gnat Creek had a much lower percentage of adult males and a
consistently higher percentage of Seeks (average of 565 and range from 43 to
CO%).
Since the yearn ievolved at each stream are not the same:. and each run
was sebjectod to different kinds of fisheries, no reason for these gross
29.
Ye
g Run
ilpt of Jacks
el
149
89
100
44
19 5.
1956-57
1957-58
1958.59
1959.60
1960.61
120
70
59
17
.24
Total
Average
365
60.8
533
88.8
+MD
I- -
1-
14C
0.922
S
r-4®1957
ifioant at 9', level}
rn
1959
tg 1958
ter" C1956
Cr%
®1961
0
10
30
50
70
90
110
130
Number of Adults in Following Year
Figure 4 Relationship of :lumbers of Silver Salmon
Jacks in Ono Year to Adults in the Fo11ou.
lug Year at Gnat Creak, October 1956 January 1961.
WWWW
-4
(7
a-4
to,
WWWW WW
4%..ts-NNO4P-401.71T,5dhIgi
AaP:AMiUM
HW
rrvrry 24r;,-)eevv.:Jvv
tautttrtst-itt--,t
n' M'Ot-"8"CIT-119g
mot,
1-0-4
gf
Ww
1.4
WWWWWWWWWWWWWWWWW
Vet
6:8
g5
4-54-t 00 Mgn§1.2VAMin s&
08tt
Vi"
k.O*4004?
F
,4;('',MNVV112
Vit40,N=.1P
.-0"b11
'.-'2Sttt
WWWF4,41-,,4
ttt-IN851
Hwv14%.0
Oa04=-.0WON-4
%HIM
t? 31,.iMPV
N 8.oPV=4
6:coti8Ei
88tt(.3
et ,gngf2
s.1
.0.04,0*%0 10
FR
co
Location
Waddell Cr.
(Contid)
1937
1938
1939
1940
1941
Average
Total
(Cont'd).
Per
Per
jagalksi._
22
26
47
47
39
126
40
20
17
3.03
51
52
50
33
75
Total
8,4
86
266
263
147
7
2,218
24
20
20
25
44
246
971
108
65
379
42
17
D.
39
33
36
41
.11.
Per
Table 8,,
42
29
88
95
61
868
96
31,
32.
differences is offered.
attempt eras Inde by scale analysis to deternine
if the larger -- sized dourstrean niarants contributed to the production of jacks.
Cirouli counts and neasurenents from the focus through first annulus were
made for nearly all silver salmon returning to Gnat Creek from the 1958 brood
and were separated into two groupe--jacks and adults,
These 196061 data are
presented in Figure 17; the overlapping dispersion of the jacks fdots) and
adults (crosses) saggeats that jacks resulting from natural rearing :ere
produced from a mixture of sizes at the time of downstream ration.
A non - significant correlation coefficient of 0.20 resulted between the
average fork lereeths of the molts for the 1954-through 1959-brood year° and
the resulting members of jacks returning to the weir in the fall and winter
of the sane year.
Likewise, no eignificant correlation existeel between the
average sizes of the enolta and the percentage of the run returning as jacks,
This lack of correlation nay be due to the lsel: of any large variation in the
annual average lengths of the snolts.
A sunmnry of all silver mmlmon marking exporinents at Gnat Creek is contained in Tables9 and 10.
The purposes of each experiment are included in
Table 9 and all experiments utilized wild fish except for one small group of
631 hatchery yearlings.
The actual recoveries are ahown in Table 10; due to
the snail numbers involved it is doubtful if any extrapolations involving
total calculated recoveries in the connercial fisheries are justified.
The
total actual recovery of 1955-brood wild yearlings marked LV was 77 while
those of the hatchery yearlings marked RV was 14.
Since about five times as
many wild migrant° were originally marked the survival rates of the two groups
were similar.
Survival rates of various yearling groups (where aver 4000 were released)
returning to the weir as jacks and adults combined are:
1954 brood . 3.0%,
1955 brood - 2.35, 1956 brood - 103%1 and 1958 brood - 3.2%.
average survival rate was 1.5%0
The over-ell
0
2
4
6
8
10
12
16
18
20
22
24
26
28
30
32
34'
36
38
15
30
60
75
90
105
120
X
64
135
1141101
X
150
%
ire
I
165
X
X
180
195
210
A Scatter Diagram Showing the Relationship Between Circuli Counts
and Distances from Focus through First Annulus, 1958 Brood,
Distance from Focus through First Annulus (Unitsof ]J40 x 150)
45
Adults (32) n = 18
Jacks (22) n = 58
Figure 17.
0
Compare Natural &
Batch. Yearlings
Survival of Natural
Yearlings
Compare Survival o
Fingerlings and
Yearlings
Compare Returns of
3 Segments of
RV
LP-LM
RP-LM
LP-RM
An
LP
RP
1955
1955
1955
1956
1957
1957
1958
1958
1958
2,
3.
5,
6,
6.
1959
7.
RV
RP
LP
Natural Migrants
Compare Returns
of 3 Segments
of 1958-Brood
Natural Migrants
1958 -Brood
Compare Fingerling
and Yearling
Returns
H = Hatchery; W = Wild,
1959
7.
1/
1959
7.
LV
Ad
Survival of Natural
Yearlings
2.
RP
W
W
W
w
W
W
W
W
W
H
W
W
Id
Gnat Creek
Gnat Creek
Gnat Creek
Gnat Creek
Gnat Creek
Gnat Creek
Gnat Creek
Gnat Creek
Gnat Creek
Big Creek
Gnat Creek
Gnat Creek
Gnat Creek
Marking Information
H or
Purpose of
Origin of
Experiment
W V
Eggs
1954
Mark
1.
No,
Brood
Year
0
0
1+
1+
I+
1+
0
0
0
1+
1+
1+
0
1+
1+
(0 or 1 +)
Ago
6/27/60
8/29/601/15/61
1/166/16/61
4/12 -
6/10/60
2/66/29/59
9/27/591/15/60
1/29/59
2/5/596/15/59
10/9/58 -
11/28/576/13/58
4/57
12/56-
6/15/57
2,974
311
118
1,013
156
264
934
113
1,806
631
2,995
116
3,112
mm
mm
mm
mm
4,6 in
3,5 in
3,0 in
4,6 in
4.0 in
1,3-3.5 in
3:2-5.9 in
3.4 in
2.0-5.8 in
141 mm
76
94
92
112
119 tra
9? pm
Release Information
Number
Ave. Length
10 6/56-
e/3/56
11/15/56
6/17/56
1/1/56
Date
Summary of Marking Experiments for Silver Salmon at Gnat Creek.
Fxpt.
Table 9
Sp,
Cie,
Sp
5 2/
22/
0 2
00 00 00 00
00 00 00
0 0
0 0
0 0
0 0
RV
LP-LM 0 0
RP-LH 0 0
LP-RM 0 0
1955
1956
1957
1957
1958
1958
3.
40
5.
5,
6 ,
6.
6-
7
25
0
0
0
00 00 00 00
02 00 00 00
00 00 10 00
An
LP
RP
LP
RP
RV
1958
1959
1959
1959
7
7,
7.
2/
27
3
0
8
1
10
8
50
2
57
Total
Commeroiftl, Sp,--t Sport, R=Random, S=Selected.
BC = Blg Creek Hatchery.
J Partial count 3f adults at time of writing in 1962.
26
1
0
8
0 0
0
10
0 0
0
6
43
1
0 0
0 0
1
57
Gnat
Creek
0
0 0
1 2./
LV
0 0
1955
0 0
2c,
0 0
0 0
Ad
0
1955
0 0
1954
0 0
acks
Other
0 0
0 0
RS RS RS RS
Cm.
Ocean 17
River
Sp,
jutT
f-;41,
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
00 00
0 1
0 0
01 00 20 00
00 01 20 00
0 0
1 0
0 0
01 00 00 00
00 00 00 00
00 00 00 00
0 0
0 0
0 6 14 0
R S RSRS RS
7/717--13p_
Ocean
0
0
3
0
od
21 V
9
3
0
5
0
14
6
27
2
62
36
6
0
13
1
24
14
77
4
119
Tear
Total
....!
Total
-.11..MM=.111
6
0
0
0
13
3
27
0
37
Gnat
Creek
0
0
3 2/
0
2 3/
5 2/
Adults
Other
Summary of Recovery Data for Silver Salmon Marking Experiments at Gnat Creek.
RP
1.
Ex PI.
Va.
Table 10-
360
Nearly all jacks and adults that returned to Gnat Creek wore measured.
Appendix Tables I . VI show length.frequeney tabulations by sex and nark for
each inch interval from 1956.61.
Data from 5 years, 1957-611 were then com.
bined into two separate groups, viz., marked and unmarked.
The mean length
of the marked fish was 2004 inches (nueher = 227; variance = 31.719; and
standard deviation = 50632).
The mean length of the unmarked group was 21.50
inches (n = 412; e2 = 31.472; s = 5.610).
In making a comparison of the two
moans with unpaired observations and nearly equal variances, the null hypothesis was made that the means of the two groups were equal and a t.test was
used (Steel and Torte, p. 73).
table value for t
Since the computed t-alue uas 2.505 and the
(637 d.f.) = 1.960, the hypothesis we
.05
rejected.
Theee
results suggest that something affected the growth of marked fish to make their
average size smaller than that of the unmarked group.
An effort to refine the estimates of potential egg deposition was undertaken in 1961.
Since it was inadvisable to kill any Gnat Creek fish in order
to count the eggs, a sample of 2 females from each inch interval from 22 to
31 inches was taken from the lower Columtia River coruercial gill -net fishery
in late September.
Details of the collection of fish, the Hid- counting of
all eggs by ovary, and the analyses of these fecundity data compared with
data from other areas, are presented in a separate paper
The relation-
ship of fecundity to length was found to be linear for the Columbia River
sample; the summary of the regression analysis is presented in Figure 11.
The regression equation io Y = 239.433 (x)
3,345.033.
The increase in egg
content is about 240 eggs for each inch increase in length of fish.
The po-
tential egg deposition for each year of operation at Gnat Creek was based on
fish length and the above linear equation and the subsequent computed numbers
of eggs spawned above the weir are included in Table 11.
Fecundity of silver salmon
c
America. R. A. Willie (in preparat on
Xieutch) in northwestern North
37.
.1.101.
5
n = 20
r = 0.85
= 239.433 (x) - 3,345.003
Std. Error of Fst. 45335
4
3
C
2
0
22
Figure 18,
26
Fork Length in Inches
2L
28
The Relationship of Fecundity to Length for Columbia
River Silver Salmon Sample, 1961.
3
3
7
5
26
27
28
29
30
31
32
2,880
3,120
3,359
3,599
3.838
4,077
4,317
Total Cale. No, Eggs
Total No. Females
1
25
2,641
17.995
23,513
9.360
8,640
2,641
26
0
89.254
4,077
0
24
2,401
1
0
23
--
23,028
0
22
1,922
6
0
1955
No
Caic.
Females No,
Fogs
21
Inches
in
Fork
Length
1,683
Computed
Ova Counts
(from
LengthFecundity
F cation
Table 11.
29
1
92,144
4017
4,077
1
219,076
45
40
67
121,916
15,352
4
137,510
8,154
14,396
4
2
30,231
9
12,480
31,680
11
4
10,564
7,203
2,162
1,922
3,366
4
3
1
1
2
0
0
15,352
17,995
20,154
28,080
17,280
10,564
4,802
2,162
3,844
1,683
Eggs
Cale.
Females No.
1959
No.
0
8,154
4
5
6
9
6
4
2
1
2
1
No.
Females
Eggs
Cale.
1958
No.
0
2
30,704
8
7,676
2
39,589
11
10,797
3
53.7144
16
33,590
28,080
46,080
10
16
9
20,160
7,923
4,802
0
7
5,282
2
3
2
2,401
1
o
0
Eggs
Caic.
Females No,
0
3,844
197
No.
0
2
0
No.
Females
Eggs
Cale.
No.
1956
Computations for Deriving the Potential Egg Deposition for
Silver Salmon at Gnat Creek from 1955-61 Runs.
16
8
1
1
3
6
4
0
27,591
8,154
7,676
OM MO
9.360
1
_
0
0
0
2,401
ACI.
0
0
2,641
- --
Eggs
53,987
4,077
3,838
10,797
20,154
12,480
Femalea
Cale.
No.
1961
No.
0
2
2
0
0
3
0
0
1
0
0
No.
Females
Eggs
Cale.
1960
No.
39,,
Juvenile Silver Salmon
Silver salmon juveniles are eeparate3 into two groups possesaing different habits, characteristics, and mortality rates.
One group consists of
fisheof-the-year and are often referred to an 0+, fry, or fingerlings.
They
are less than one year of age and do not appear to contribute to the adult
population if they migrate to sea at this age.
Hunter at Port John, British
Columbia, counted 200000 fry per year (Boer, 1951) and Wickott (1951) counted
varying numbers between 700 and 2,800 into the intertidal zones and concluded
that the majority perished.
Harr (1944) axanined the seales from 885 Columbia
River silver salmon from the 1914 run and found no fish of the 0+ group.
The
time of migration for the second group, called yearlings, 1+, or smelts,
occurs mostly at 12-14 nonths of age.
Counts of these fish for each brood
year chile the weir was in operation from 3ovember 16 of one year through the
end of migration the following summer are summarized in Table 12.
It is
readily apparent that moat molts counted at the weir migrated in the spring
and that of those counted only 4% of the 6-year average migrated in the latter
half of Uovenber.
Of the 2,217 (6-year average) counted, 7i
migrated into
brackish water during the month of May and 90% migrated in April and May combined.
By referring to Table 2 and Fi7ure 14 it can be seen that no eater
spilled over the dam during these tee spring months in 3 (1956, 1958, and 1959)
of the 6 years.
The time of nigration at Gnat Creek is generally Sirri3Ar to
that at nintor Crooks
Creek, and Taku River (Meehan and ainiff, 1962).
When spawning grounds are looted on anall hoadvater tributaries which are
also farther from salt eater, the tine of yearling migration appears to be
earlier.
At Spring Creek this peek occurred regularly in late March and early
April and was closely associated with increased flows (Willis, 1955 typed
manuscript), /.
At Deer Creek, Alsea River, OCC personnel found a sharp peak
of molts in March (Chapman, Conies, Phillips, and Dowry, 1961).
A graph
Ro A., 1955. Downstream migration studies of silver and chinook
Oreg. Fish Camm. Typouritton
salmon in certain Oregon coastal areas
rnnuscrint. 28 n
Table 12.
5-Day Period
Ending 1/
0
170
2
62
5
64
4
5
27
6
5
23
17
5
4
8
0
10
11
3
3
0
4
0
9
5
2
2
3
0
1
0
0
0
2
13
0
20
5
0
25
6
0
18
13
5
3
0
0
30
5
10
15
20
25
30
0
7
0
0
2
0
7
5
2
11
2
9
17
6
22
3
2
6
0
10
19
3
5
1
7
10
8
14
18
43
28
46
Nov.
20
25
30
5
10
Feb.
Mar.,
Apr.
May
June
July
otal
1955
Day
Jan.
Brood Year
1956
1957
1954
Mo.
Dec.
Count& of Wild Juvenile Silver Salmon Migrants at Gnat
Creek Weir by 5-Day Periods from November 16 to End of
Migration Year, 1954-59 Brood Years,
15
20
25
30
5
10
15
5
10
15
20
25
30
5
10
15
20
25
30
5
10
15
20
25
30
5
10
15
20
25
30
5
10
15
20
4
3
il
1
3
9
0
7
26
16
60
168
245
509
351
542
516
332
106
33
11
2
0
0
0
0
0
41
31
4
62
92
221
295
.544
320
515
216
124
45
9
1
0
0
0
0
0
0
29
9
for Febrartrro
1959
3
10
101
11
3
2
6
6
2
-Year
Average
33
33
313
120
115
52
20
19
9
51
9
12
3
4
43
42
7
7
4
1
0
1
24
4
19
15
3
13
2
8
11
13
11
6
5
3
0
0
3
0
1
1
4
1
2
5
0
6
3
8
1
48
31
8
23
17
4
1
15
3
1
3
16
16
0
0
8
44
3
7
0
3
3
5
2
18
z4
24
0
69
3
5
2
2
3
3
4
9
1
14
8
16
2
1
9
35
32
22
33
42
4
12
6
3
0
0
2
1
1
1
13
40
54
17
12
20
312
235
399
341
143
22
5
2
0
0
0
0
1
0
L1146
1.847
2
V Six days ere included in lest per
leap yatr)
1958
3
2
4
13
47
36
216
30
40
72
37
48
188
128
108
81
46
75
155
181
271
3
34
15
2
8
2
0
0
0
0
0
0
0
0
1.01'
6
26
0
0
0
0
0
1.061
for 31-clay nanths
2
11
43
129
72
91
135
69
355
487
396
84
130
199
189
312
430
758
1,027
2.055
1.671
442 2.297
256 1,440
257
971
384
150
29
86
4
20
3
0
0
0
1
1
0
0
0
0
0
5
3
5
4
5
7
14
22
33
32
52
72
126
171
343
279
383
240
162
64
14
3
1
0
.
(2,217)
e istvs
four'.
226 1
4O
Table 12,
5-Day Period
Fnd
1
o.
lay
Nov.
20
25
30
Dec.
Jan.
Feb.
Mar.
Apr.
May
June
5
10
15
20
25
30
5
r
. .
Brood Year
1956
1955
0
2
5
170
62
64
4
5
27
6
29
9
5
23
17
3
3
0
9
5
2
4
3
44
V
1
3
U
1%141 6-!ear
7937 -13951957
1954
3
10
101
11
2
3
6
5
6
4
2
33
33
9
12
8
0
3
4
10
3
0
1
1
4
1
0
0
0
0
2
3
11
13
11
5
3
0
0
3
10
4
0
2
15
20
25
30
13
5
0
0
6
0
18
13
5
0
7
0
0
2
0
8
4
1
2
0
7
5
0
9
0
7
26
5
2
6
11
16
9
17
6
22
3
2
0
1
0
0
3
24
3
1
2
1
1
3
5
3
5
10
3
1
3
2
9
B
1
14
16
13
40
54
17
3
2
1
9
13
6
5
10
15
20
25
30
5
10
15
20
25
30
5
10
15
20
25
30
5
10
15
20
25
30
5
10
15
20
25
30
July
Counts of Wild Juvenile Silver Salmon Migrants at Gnat
Creek Weir by 5-Day Periods from November 16 to End of
Migration Year, 1954-59 Brood Years.
5
10
15
20
16
2
10
19
7
8
14
18
43
28
60
168
245
509
351
542
516
332
106
46
41
31
4
62
92
221
295
544
320
515
216
0
0
0
6
0
12
20
2
4
47
36
216
26
30
40
37
72
75
48
155
124
312
235
399
341
143
188
128
108
81
181
271
3
34
15
8
0
0
0
0
0
0
45
22
46
33
9
5
11
1
2
0
0
0
0
0
0
0
0
0
0
2
0
2
2
0
0
0
0
0
6
0
0
0
1
0
i4;
2
1 84
Six days are included in last par
lean year) for Febrourvr,
0
0
0
Average
313
120
115
51
43
42
24
19
15
13
8
1
48
31
23
1
1
17
15
0
3
16
8
44
18
24
69
5
2
0
2
2
4
11
43
129
72
91
185
69
355
487
396
442
256
257
150
29
4
3
3
2
1
8
5
4
3
3
3
7
3
4
12
35
32
22
33
42
6
5
84
14
130
199
189
312
430
758
22
1,027
2,055
1,671
2,297
1,440
971
384
86
4
20
1
3
0
0
0
0
0
0
0
52
20
19
9
7
7
4
5
7
33
32
52
72
126
171
3&3
279
383
240
162
64
14
3
1
0
1
0
(2,217)
1 01
or
1 0.1
2261
-day nonths; three
ays
four-
41e
showing tho numbers of migrants and average flown by 5-day intervals for the
1958 -brood fish that migrsted downetream at Gnat Creek in 1959 and 1960 is
included as Figure 19.
This figure and Figure 18 in Selo and Beyliff (1958)
appear sonewhat stmtlnr in that no close relationship exists between flows
and juvenile silvgr migration.
lowever, at Spring Creek an increase in smolt
migrants accompanied an increase in flow during days with freshets in late
March or April.
During May 9 and 10, 1962, 3.- and 6-hour counts of downstream migrants
were made at Gnat Creek.
A total of 180 silver yearlings tmre captured in
the following time periods*
30 (171 from noon-6 p.m.; 96 (53%) from 6 p.m.-
midnight; 38 (211 from midnight to 6 tznc; and 16 (91 from 6 a.m. to noon,
A total of 7,878 *molts mac noaeurod during the Gnat Creek study.
The
characteristics of the length...frequency distributions in 5-mm en-min are pre-
sented in Table 13 for each brood year,
It vas desired to compute confidence
limits to qualify the average lengths eines riot all migrants wore measured,
The numbers measured exceeded 500 except i'or the 1956 brood and it was assumed
that confidence Intervale based on a narma.1 eistributien would be suitable°
This assumption was tested in tha follow iz tanner'
(1) thu cumlative
frequency of the 6 year L7erage '.,LS tabulated in per cent an shown in Table
13; (2) the moan and stundara deviatiore mere computed; (3) the nunulative
frequency in per cent wee deternined fnr K
1, 1096, and 3 standard devia.
time, which were then plotted (asOpoin--,3) on norrel probability paper in
Figure 20.
It was also desired to cmgpare the sample dietribution (Table 14)
compoeed of 2,212 May migrants (as 0 in Figure 20) with both the 6.year
average and a true normal distribution which is shown as the straight line,
With the minor exception of each extreme, both length dietributions are
aimilar to a normal distribution,
Confidence limits at the 95% level mere
then computed and added to the bottom of Table 13 and enclosed in parentheses
in the following eentences,
The average length of all 7,878 smelts measured
100
200
20
Feb.
10
10
I
I
I
.
10
1
t
k
Apr.
//
"
1V
A
li
i%
20
Oct.
30
10
20
30
1
I
1
1
1
10
4/
\.
No-4-e
.1
I
i
i
/
%
1
...I
I /
1
k
1
N
%/%
V %
%
in.."
\.
fish
246
%
f4%
1
0
200
20
June
10
1061s.
.1 -i
I -4:771".--1-20
10
20
10
20
30
30
30
10
20
20
10
30
10
30
20
30
Apr,
Feb.
Mar.
May
Deo.
Jan,
;\
)
?.
/
400
Time of Outmigration of Juvenile Silver Salmon of the 1958
Brood and Average Daily Discharge, by 5-Day Periods, Gnat Creek Weir. 1959-60.
10
I
I
I
Nov.
...,
IN. 1-9.1-.4-id
/ % / V
Figure 190
30
Mar.
1959
20
1.I
1
30
N
k
I
N..,1
1.4.4.
.
.1
i t
r
1
I1i1
i
0
300 oof,s,
98
103
108
113
118
123
128
133
138
143
148
153
158
163
168
173
83
88
93
68
73
78
53
58
63
n
5.4
5.6
5.8
6,0
6.2
6.4
6.6
648
5,2
50
2.9
3.1
343
305
3.7
3.9
4.1
4.3
4,5
4.7
4.8
27
2.1
2.3
245
Inches
gra-rargt
1/
20.6
11,6
14.8
10.2
88-136 85-137 61-141 97-143 92-150 95135
13.3
190,90
155 40 17766 423-99 133.95 218,42 103 70
12.5
114,9
115
121
120
87.8-142,0
13.8
1,315.8
101
7,878
111
12
6
1
1
112
1
2
1
3,176
6
1,050
0
0
3
949
0
444
0
0
0
0
1
124
67
27
104.4
57.3
31.7
20.7
11.2
4.5
2,0
0,8
0.2
0.2
2522
2599
1748
11,5
11.5
21.7
22.0
24,9
46,3
89,5
160.2
868
0
23
7
45
23
13
8
69
67
130
132
149
277
536
959
1,510
1,556
1,047
625
343
190
26
1,391
1
4
68
40
17
6
55
82
70
87
128
69
695
172
171
661
453
268
101
460
42
79
233
17
33
28
5
0
2
114
55
o
1
0
3
2
8
16
25
0,2
1.8
2,0
4,3
0
11
12
0
0
0
6-Yr. Av.
0
0
0
0
1
0
0
2
2
2
22
8
3
1
0
38
28
26
41
10
20
44
102
173
151
138
125
4
2
1
6
0
0
o
0
Total
1(-A9
195A
0
0
0
0
C.F. = Cummlative i'requency,,
Length (for Normal Diet.)
95% Confidence limits of Av,
37
70
97
123
100
130
104
76
37
10
25
50
5
40
44
31
25
19
33
30
21
27
77
116
329
417
186
59
14
27
5
6
0
9
8
15
36
21
13
37
0
1
1
0
0
1
4
8
1955
1954
Frequencies
Brood Year
1957
1956
1,315,6
1,315.8
1,3154
1,296,9
1,308.1
1,312.6
1,314.6
1,2762
395.9
643,1
908-0
1,082,8
1,187,2
1,244,5
2357
19.8
31.3
53.0
75,0
99,9
146,2
8,3
2.0
4.0
.2
C.F.
for 6-Tr, Av,
0,002
0.003
0,006
1.505
2.379
4.028
5.700
7.592
11.111
17.913
300088
49.255
69.007
82,292
90,226
94,581
96.990
98,564
99.415
99.757
99.909
99.970
99.985
100.000
C.F. in
Per Cent
Characteristics of the Length-Frequency Distributions in 5-431m Groups of Wild Silver Selman Smalts
that Migrated out of Gnat Creek by Brood Year Petween November 15, 1956 and June 30, 1961.
Standard deviation in mm.
7al1 ence in mm.
Average Length in
Total (n)
51-55
56-60
61-65
66-70
71-75
76-80
81-85
86-90
91=95
96-100
101-105
106-110
111-115
116=120
121-125
126-130
131-135
136-140
141-145
146 250
151 155
156-160
161=165
166-170
171-175
Fork Lengths
Millimeters
Interval Mid Point
Table 13.
44.
9909
®
Avoraco (n = 1,315.8)
(n = 2,212)
0 1959 Brood
9905
99
98
95
I-
90
80
70
C,
60
50
30
20
10
5
2
1
0,1+.
+ 3 S,D.
;L
2 - 1 S.D.
E + 1 S.D.
Figuro 20. it Outzajirison at Pointe on TWO 44engtir-f requienoy
Distributions with a I:oriaml Distribution (shown
as a straight Line).
+ 3 S.-7_
+ 1096 S.D.
45
Table 14.
Length- Frequency Distribution of 2,212 1959-Brood
Yearling Silver Salmon, Gnat Creek, May 1961.
MM.
Fork Length
Inches
76
79
81
84
86
89
91
94
96
99
101
104
107
109
112
114
117
119
122
124
127
129
132
135
137
140
142
145
147
150
152
155
157
160
162
165
168
170
3.0
3.1
3,2
3.3
3.4
3.5
3.6
3,7
3.8
3.9
4.0
4.1
4.2
4.3
4,4
4,5
4.6
4.7
4.8
4.9
5.0
5.1
5.2
5.3
5.4
5.5
5.6
5.7
5.8
5.9
6.0
6.1
6.2
6.3
6.4
6.5
6.6
647
Total
an
0
1
1
117 mm,
4.61
0.342
Standard
Deviation
100-134 mm,
Cumulative
Frequency
o
1
2
0
0
0
2
1
3
6
22
3
16
15
54
97
138
192
227
261
293
228
187
160
131
80
39
25
11
19
7
7
3
5
2
3
0
1
1
2
1
1
2.212
8687 mm.
954 Cont,
Limits
Frequency
2
2
37
91
188
326
518
745
1,006
1,299
1,527
1,714
1,874
2.00
2,085
2,124
2.149
2,160
2,179
2,186
2,193
2,196
2,201
2,203
2,206
2,206
2,207
2,208
2,210
2,211
2,212
Cumulative
Frequency
in Per Cent
.00
.05
.09
.09
.09
.09
.14
.27
.99
1.67
4.11
8.50
14.74
23.41
33.67
45.47
58.71
69.02
77.47
84.70
90.63
94.24
96.00
97.13
97.63
98.49
98.81
99.12
99.26
99.49
99.58
99.71
99.71
99.76
99.80
99.89
99.94
99.99
6o
large sample of
was 114.9 (87.8 to 142.0) ms and the avorago lencth of the
lengths far
May migrants of the 1959 brood was 117 (100-134) mm, The average
with the
other brood years did not very a great deal from the 6 -year average
smallest being 101 (61-141) nm and the largest 121 (92.150) mm.
The averega
lengths of smelts at Spring Creek were slightly under 100 mm.
A general indication of fresh -mater growth as reflected by the fish
of the
leaving the stream is illustrated in Figure 21 for 3,414 juveniles
1959 brood. When alevins absorb the yolk sae, they are about 1.5 inches long
as shown in April.
mid.winter (Deoember) they were 4,1 inches long and
the bulk of the fish migrated in ray at an average length of 4.6 inches.
In flay 1962, 10 weight measurements were obtained for each millimeter
in length ranging from 101-135 m.
The individual weights are shown in
Table 15 with averages for each 5.mm groups
Since only 8 fee ales were re.
be.
leased above the weir in 1960, the majority of these 1962 migrants was
lieved to be from a liberation of 30,000 Big Creek Hatchery fingerlings re.
leased into Gnat Creak in June 1961 and reared naturally for about 10 months°
The weight data and the condition factors Included in Table 16 were obtained
OFC
for comparison with naturally reared fish of hatchery origin on other
projecta.
The typical Gnat Greek molt 1111,6 115 n longs weighed 15.4 grans
(27 fish/lb.), and had a condition factor of 1.01.
The average size of
Hey 1961 to
silver salmon yearlings of the same brood naturally reared from
length and
February 1962 (84/2 months) in Wahkeena Pond we 102 mm in fork
10.2 grants in weight or 44 fis)/1b. (Haas and Hillis, 1962).
The latter
group probably would have been 12 mm (1/2 inch) longer--based on information
in Figure 21.-had they been released in Mal.
Productivity
Comparisons of the annual adult silver salmon rune and resulting progeny
of silver salmon in
are shown in Table leo A summary of the productivity
t
14%y
1
C=1
2
(8)
(116)
i
(6)
(89)
(34)
(184)
1
3
Int.
5
Fork Length in Inches
4
L-1---1
1==,;:t.
r
i
(35)
11
6
(186)
1
1
7
(592)
(2,212)
r1M11.111PM.....11111111111=1
11.111M111
(5)
of the 1959 Brood at Gnat Creek Weir, April 1960-June 1961.
Salmon
Figure a. Average Lengths and Range in Side of 3,414 Downstream-Magrant Silver
April
March
February
January
December
member
October
Juno
May
April
8
(22)
a.
Tabla 15,
Fork
Length
(a)
Average Length-Weight Measurements for Yearling Silver
Salmon per Millimeter of Fork Length, 1960 Rrood.
5-mm
Mid
Point
Total
Weight of
Ten Fish
(grams)
118 9
101
1093
102
103
104
105
103
106
107
108
109
110
112.5
113,6
115.8
121.0
122.1
129,2
Average Weight
for 7ach
mm if
11.9
10.9
11,3
11.4
11.6
1321
1355
113
115
140.4
142.8
146_1
149.3
153,5
14,0
14,3
14,6
14.9
15 4
116
117
118
119
120
118
157.2
160.4
166 7
172.0
174,7
15.7
16.0
1607
179.6
184.0
18,0
1847
18,5
18,8
111
112
113
114
121
122
123
124
125
123
187.9
197,0
126
127
128
196,8
220.9
22.1
132
133
134
135
2255
2295
2373
22,6
23,0
23,7
23.6
lf
1 = 10
1 N =50
18,7
19,7
131
236.2
16.6
184
207.3
215,3
218.4
133
14,6
17 ,,5
129
130
2036
12,8
172
19,7
20,4
20.7
21,5
21,8
128
1.1.4
12,.1
12;2
12.9
13.2
13.6
108
Average Weight
Per 5-mm
Interval 2/
20,.8
23,0
49Q
Table 16.
Fork
Length
5 -ma
MidPoint
Average Condition Factors 11 for Yearling Silver Salmon
per Millimeter of Fork Length, 1960 Rrood,
Average for
Each mm
verage Per 5,...mm
Interval
1.04
101
102
104
1.03
1.03
101
105
1.00
106
107
108
109
1.02
1.00
1.03
103
103
108
1.03
1.02
110
1002
1,02
111
112
113
114
115
113
1.03
1.02
1.01
1.01
1.01
1.02
118
1,01
1,00
1.02
1,02
1.01
1.01
116
117
118
119
120
1.01
1.01
121
122
123
0.99
123
1.01
124
125
0.99
126
127
128
129
130
128
0,98
0099
o.99
1.00
1.00
0.99
133
0.98
0,98
0.98
0.99
0.96
0,98
1.01
131
132
133
134
135
Condition Factor = 100x000 Teip
L3
2/
is fork length in millimeters,
N = 10
M = 50
where W is weight in grams and
1,061
3,226
975
398
236
209
170
103
67
79
67
40
45
8
16
89
100
44
70
55
53
30
14
9
8
1957
1958
1959
1960
1961
17,258
3,494
1,459
1961-62
1960-61
1959-60
1958-59
1957-58
3,811
1,993
1956-57
3,215
____glitaarAUZL
of
Year
1/ Counts represent minimum numbers since some fisb are known to bypass countinc7 facilities at the
weir and escape over the data when volumes exceed 150-200 c.f,e.
2/ November 15 arbitrarily aclootad as tbe data to capr'.rats finorlin4s frail :molts.
3/ Of the 13,148, 13,046 were of hatchery origin, being larger in size and different in coloration
while 102 were wild.
13,148 3/ 4,110
1,013
1,847
1,964
224
29
149
46
1956
2,996
219
174
26
Resultant Outnigration
._____INum rs of Fi
Jota,.
Smorip
81
------
67
Size of Parent Run
at Gnat Creek, 195559 Brood Team
Comparisons of Annual Adult Silver Salmon Runs and Resultin7 Pro7eny
1955
Year of
Parent Run
Table 17
510
Gnat Creek based on estimated egg deposition weir counts of 1uveniles and counts
of returning jacks and adults is presented in Table 18.
The counts of adult
males, jacks, and females are believed to be accurate although some fish may
have returned from the occasional spawners in the small area available below
the weir or strays from other streams.
The fingerling counts for zero-aged
fish that miTated between emergence in the spring and November 15 of the same
year are subject to errors of varying magnitude but probably not as great as
that indicated in Table 4 for fall chinook fry and fingerlings.
The smolt
counts are accurate for the 1956 and 1957 wood years that migrated when there
was no spill of consequence over the dam in April and Hay 1958 and 1959.
In
1961 a liberation of 30,000 3-conthreold hatchery.. eared fingerlings was made
into the pond outlet at the newly-constructed OGG hatchery.
The 30,000
stocking rate was derived by productivity and streameeize relationships by
Wallis (1961) .
It was desired that these fish not be affected by any nark
and the objective was to doternine if any gross differences would result in
the subsequent smolt count which had previously varied from about 1,000 to
3,200 with an average of about 2::000 or 145% of the average maximum egg depo
sition.
From the results in Table 18 the number of fingerling migrants; in-
creased nearly 7-Cold over the earlier maximum count, and the yearling smolt
count was 1.27 times higher than the previms naximum count.
The average
survival of fingerlings (reared 3 months in a hatchery) to yearling migrants
was determined to be approximately
at Minter Creek (Salo and Begliff, 1958).
The average seat survival (1955 -59) of 2,029 from 41 females indicates ve
night have expected
&mu t)
females placed above.
or less than 400 1960-brood smolts from the 8
41
This suggests that. 3700 of the 4,100 counted night
.
have been contributed from the hatchery liberation.
Scales were collected
Pram a random sample of manta but were not analyzed for this report.
From
data in Table 18 the returning jacks and adults have averaged only 122r, of
219,076
67
40
45
1957
1958
1959
41
131,980
659,900
.22121
137,510
758
3,792
11A3
236
398
975
19964
219
/
0,6
2,029
10,143
3,226
1,062
OA
0.2
1, 013
1,847
2,996
Rot
No of Adult
Males and
Per Cent
of Parent
1/
Primarily hatchery fish.
V Partial count of adults in 1962,
Per Cent Per Cent
of
of Eggs
1.5
2.3
50
251
81
24
17
005
0.9
59
70
2.0
3.3
122
180
60
25
203
269
0,04
0,06
0.02
0.01
0.06
0.08
IM
2.5
..11
2.5 Zi
203
1.7
3..2
2.3
---F....1"..1------.1----
Smolt Survil,_ ,
Number Per Cent
of Eggs
0.4
2.1
0,2
rineerling survival
Number Per Cent
of Eggs
i7- Does not include fingerlings or amolts passing over spillway when flows exceeded 135-150.
Average
(1955-59)
(1955 -59)
Total
207
929144
29
1956
1960
89,254
26
1955
121,916
Calculated
Egg
Deposition
No. of
Females
Above Weir
Survival Rates of Silver Salmon Based on Calculated Egg Deposition,
Juvenile4ligrent Counts, and Resultant Adults Returning to Gnat
Creek Weir, 1955-60 Brood Years.
Year of
Parent Run
(Brood Year)
Table 18.
53.
the parent females.
Ia order to naintain the runs we should expect 2005 or
1 male and 1 female to return to spawn for each parent female.
The average
return of adults only to Gnat Creek has been 50 or 2.5% of the average number
(2,029) of molts counted.
The possibility of incomplete juvenile counts
at the weir indicates that smolt survival nay be somewhat higher than this,
and the return of adults would be correspondingly lower.
An attempt uaz made to determine if any relationship existed between the
Columbia River commercial gill-net catch, the number of Gnat Creek adults,
and a runoff indexe-oleilftr to that used by Sinker (1953)--two years earlier*
The derivation of the Index was given previouely and is listed in Table 19
with estimates of the total catches in the lover Columbia River two years later.
Although the data are insufficient for statistical analysis, a general relation,ship between the comeercial catch and total meter quantity is apparent sinews
the highest catch is accompanied by the highest runoff index 2 years earlier
and the lowest catch is accompanied by the lowest water quantity index 2
years earlier.
10 relationship was present between the number of Gnat Creek
adults and the leadoff index two years earlier.
Steelhead Trout
Although the study of oteelhead was not included in the original Gnat
Creek project objectives, some interesting information was obtained.
The
total nuebera of adult ateelhead returning to the weir from 195-62 are
listed in Table 20.
The spawned-out adults that returned downstrean were
also counted; the percentage survival averaged 57.5% and varied between 11.5
and 81.31%
The adult run varied between 41 and 262 fish and averaged 1234
An average of 1,467 migrants wan produced of which 104 were seroeaged fish
(Table 21).
A use of the random peeplleg device shown previously (Figure 13) was
tested as to the accuraoy of a 20% sample in portraying the size composition
54.
Table 19,
A Comparison of Columbia River Gill-Net Catches
and Gnat Creek Laults with Runoff Index Two
Year Darner.
....Stamorsalia..gliZzlittAtaaaa
Tsar
Via h
_2:on
Total
Chat
Greek
Adults
Gnat creek
Runoff
Index
2 Years
Def9re
1958
6,152
12,645
18,797
70
67.62
1959
3,770
11,039
14,809
59
39.21
1960
3,499
12,933
16,432
17
56010
1961
11,900
28,996
40,896
24
81.82
1962
-
aa. 2/
49.62
Pirg-zo77st
.
.
_Asjtesant Department of
Fisheries
o7d 11311 records.
2,/ Nearly complete counts*
Table 20,
jumbors of Adult Stealhead Counted at Gnat Creek
Weir During Upstream Migration and Survival after
Spawning, 1955-62.
Calendar
Year
1955-56
1956-57
1957-58
1958-59
1959-60
1960-61
Per Cent of Upstream
Nigrante Captured at
262
234
60
114
41
213
154
30
53
10
6
8103
6508
50.0
46.5
1104
1406
1961 -62
Total
7-Year Average
864
12304
497
71.0
5705
550
Table 210
Calendar
Ilmbors of Wild Juvenile Steelhead Outnigrants
Trapped at Gnat Creek Heir, January 1, 1956 June 25, 1962.
Age Group
0
1956
1957
1958
1959
1960
1961
1962
286
89
18
110
Total
7-Year Average
731
Ace Groups
I
209
19
'
Total
I
31489
2,048
1,237
988
1,241
1,663
1,203
1,959
1,219
878
1,032
1, 644
LkSIZ
104.4
10,268
1,466.9
9,537
1,362.4
of all steolhead juveniles that migrated during the spring of 1961.
The
results of the sapp/e lengths are compared graphioal1y in Figure 22
lengths for all fish caught of age groups
Y, I2,
and III combined.
By using
these sampling data and by further examination of the scales in the sample,
the age composition of the downstream juveniles could have been determined.
Although insufficient time was available for working up these data prior to
preparing this report, steelhead age-length data and earlier material on
chinook and silver salmon have been summarised in a sunnau report of Gnat
Creek Weir Operations, June 1958.June 1959 by Thomas E. Kruse.
It was shown
that extent of overlapping lengths prevented separation of ateelhead into brood
years from length-frequency distributions.
summary of steolhoad marking experiments is shown in Table 22.
The
primary objective of marking steelhead was to identify Gnat Creek fish and
determine the numbers of subsequent returning adults.
Marked OGC hatchery
fish of the 1960 brood (as well es unmarked fish) escaped downstream from
"c;
0
50
100
1
3
Figure 22.
6
Length in Inches
7
8
Comparison of Length-Frequency Distributions of Juvenile Steelhead
Taken by a Sampling Technique with the Entire Population, 1961.
5
IRandom Sample
n=319
n=1644
Entire Population
Big Creek
Hatablexq
RV
1,015
222
1
1
18
152
27
20
3
892
64
25
1,630
Re_leftied
Numbers
5/24/61
2/18-9/6/61
1/15/61
4/1-6/64 -
10/2/59
10/20/593/30/60
10/1015/4-
3/23-6/11/57
Date of
Re12mt3
36
1
0
59
10
71
2
jmtExo Ljtelorgzed
1t
Ye
Rec
~iv
1961-62
1962
1959-62
1958
1959
1960
__of
Summary of Trformation Relatin7 to Steelhoad
Mark Experiments at Gnat Creek, Through June 1962,
Brood year as determined by length-frequency data except for the hatchery fish.
1960
Ad-only
Total
LM'-only
Ad- M
LP-only
Gnat Creek BV
Ad-BV
Hatchery
Ad-.RP
1957-58
1960
d-LP
D-Ad
Natural
1958
1957-58
Ad
Mark
Natural
Stook
1955
Brood
Itar_lL___
Table 22,
rare
other anticipated narking experiments.
A Krayelleeletn scoop trap eas tested at
Gnat Creek with 1;015 hachery-reared juveniles (6.5 inches long and about 9
fish/lb.) of the 1960 brood being narked RV and liberated 200 feet upstream
from the trap on nay 24, 1961.
It was found that soma of those fish could
ewtm back out of the scoop trap at strotm velocities of 3.0-3.5 feet p©r
second.
The best operating velocities are higher than this
Additional de-
tails of adult steolhead recoveries were presentod in the Operational Studies
annual progress report for 1962.
Out of 65 adults that returned in the 1961
run, I2 had a variety of different marks, and 36 of these were Ad. PO
Another side experiment using steelhead was conducted at Gnat Creek
between Deoenber 1955 and June 1958 to compare the uee of spaghetti with
Petersen tags; the former were more eatiafactagefrom the standpoint of tag
lose.
These data have been summarized in a typed manuscript (Kruse, 1959).
Miscellenrous Species
Counts of adult and juvenile cutthroat trout, laereey
trtdeetqttia), and cottida (22111.41 spa) are taletInteel in Table 23.
The numbers
of adul,', cutthroat trout declined from 583 in 1955-56 to 115 in 1959-60.
but increased to 254 in 1961-62,
In some years nore laeprey adults were
counted going downstream than were counted going upatream.
This uas due
to their abilik to cling to the dam and pass over the weir without entering
the upstream trap.
SMEARY AID CONCLUSIONS
Gnat Creek drains a 22-square-mile area.
Flows fluctuated beteeen
1,300 and 7 a.f.s. betweon the start of the project in October 1955 and its
termination in Jura 1962.
A partiellyepaesable =sleds located 3 nibs above
the weir prevented papsage of adult rigrant© during low flows.
A modern
590
Table 23.
Miscellaneous Species of Fish Enunerated at
Grat Creek Weir, October 1, 1955. -June 30, 1962.
Species
Up
Cutthroat
Adults
Juveniles
Down
Up
Down
Up
Down
142
13
5
1,694
8
1,631
2,880
--
1,502
1,796
457
624
1,368
96
2,329
554
14
87
2,706
355
Lamprey
Adults
1,773
Juveniles
--
1,022
4,345
378
--
959
4,566
Cottids
1,231
--
477
_1251.7.0
330
1960..61
Dp
Cutthroat
Adults
Juveniles
115
Lamprey
Adults
Juveniles
178
Cottids
1
1,405
186
269
859
173
180
3
24
1,592
254
49
--
1,546
897
3,549
355
--
210
1,687
363
Down.
15
583
34
Species
Up
233
135
6O
hatchery was constructed near this location in the summer of 1960.
The problem
of adequately sampling the numbers of juvenile fish going over the dam during
floods was not entirely solved although substantial effort vas expended.
Data
from sampling traps on the dam during fall chinook nitration suggest that 86%
of the estimated total chinook migrants from January through April went over
the spilluey.
Data are presented to show that in certain years no spill took
place during the major migration period for juvenile silver salmon and steelhead trout in April and ney.
The adult counts are conaiderod to be accurate
and tha average number and range of mature fish (jacks included) of each species
was 39 (2-88) fall ehieecik, 149 (79.224) silvers, and 123 (41 -262) steolhead.
Juvenile production yes based on weir counts.
had visible yolk sacs and appeared to be dislodged.
Many of the chinook fry
Based on a 6-year average,
71% of the yearling silvers migrated in the month of May and 905 migrated in
April and May.
nest amolts nigrated between 6 pr,n, and midnight when counted
on nay 9 and 10, 1962.
The average lengths of 70878 smelts from 6 brood years
averaged 114.9 mm with 95
Yearlings from
confidence limits of 87.8-142.0 nme
individual brood years had average lengths that ranged from 1014.21 nee
Average
weights and condition factors are presented for one group of migrants°
An estimate of the silver salmon potential egg deposition at Gnat Creek
was based on the individual egg counts of 20 females caught in the lower
Columbia River comnercial fishery.
inch in length from 22 to 31 inches.
This sample contained two fish from each
The regression of fecundity on length
was linear and the equation for the calculated egg content MSS
CO
3,345.033.
i a 239.433
The calculated egg deposition at Gnat Creek varied between
27,591 for 8 females to 219,076
or 67 fenales,
The average estimated sur-
vival to yearling migrants was 1.5% of the computx1 egg deposition and
varied between 0.5 and 3.3%.
If complete counts of yearlings had been ob-
tained these survival figures may have been somewhat higher.
Survival
rates of 0.5 and 2.05 for tee hrocji years are Pram accurate counts,
On the
61.
average, 2.5% of the snolts counted returned to the weir as adults (jacks exeluded).
Complete enuneration of smolts would tend to lower this figure.
From accurate counts of hatchery-reared, narked chinook fingerlings liberated between April and June 3 miles upstream, fresh
ter survivals of 50-885
were obtained with half the numbers reaching the weir within 2 to 5 days after
liberation.
Most of the surviving adults 00 returned to the stream from a
yearling release.
One marking experiment (631 silver salmon) was undertaken
to make a comparison between hatchery and wild yearlings.
The survival rates
of these two groups were aisiiles using total actual recoveries since about
5 times as rimy wild fish were origleelly narked.
A comparison of the average lengths of marked and unmarked silver salmon
that returned to Gnat Creek Weir from 1956 through 1961 was made.
Two-
hundred twenty-seven narked fish aversged 20.34 inches and 412 unmarked fish
averaged 21.50 inches. A t-test of the means indicated the difference was
significant at the 5% level*
The total Columbia River commercial gill-net catches and a runoff index
at Gnat Creek two years earlier (from the type of relationship established
in western 4ashington by Dr. Smoker) sAggests a possible relationship but
insufficient data were available for a statistical test.
NO relationship
between Gnat Creek adults and the index was apparent.
The production of juveniles from varying numbers of adults is presented
for ohinook and silver salmon and steelhead and cui.throat trout.
Produotivity
and survival rates for silver salmon was related to the calculated egg deposition, 0+ and smolt counts, and adults in the progeny run from the numbers
of amolts counted,'
62.
ACKUOWIEDGMENTS
Funds for the project and other assistance were provided by tho U. S.
Fish and Wild31fe Service, Bureau of Commercial Fisheries, under the Columbia
River Fishery Development Program)
Aelmouledgnent is clue to Alphonse
Kennerieh (BCF) for his help and coordination and the OFC Engineering and
Fish GUlture Divisions for their assistance and cooperation.
Project per.
sonnel who worked on the Gnat Greek studies at various tines were Chester
Mattson, Ernest Jeffries, William Sweeney, Robert McQueen, Thomas Krus©,
James Haas, Larry Bram, and Truman Cummings.
Earl Pulford and other arc
personnel gave their time and energies when added help was needed.
Collins and Larry Ilreha aided with the tabulation of data.
and Robert Gunecaus reviewed the final report*
Melvin
Jack II. Van liming
63.
LITERATURE C
Chapman, Donald W., John F Corlissl Robert W. Phillips, and Robert L. Demory.
Orsg. State Univ. Agric.
1961. Summary report Alsea watershed study
Expt. Sta. Vine. Paper 110s 52 p,
Baas, James B., and Thomas r Kruse. 1961. Gnat Creek Weir studies. Oreg.
Fish Comm. appraisal of project results annual prop. rep., proocsiec1, 28-62 p.
Haas, James B., and Raymond A. Willis. 1962. Wahkeena natural rearing study
of silver salmon. Oreg. Fish Comm., annual proi:. rep., processed, 31 p.
Hoar, William S. 1951, The behaviour of chum, pink, and coho salmon in relation to their seaward migration. Jour, Fishones. 1)d. Canada 8(4):
241..263.
Hrehal Lorry N., and Raymond A. Willis. 1962. Gnat Creek Weir studies.
Fish Comm. annual progress report, processed, 13 p
Orc7,.
Kruse, Thomas E. 19590 A comparison of spaghetti and Peterson tags used in
steelhead trout at Gnat Creek, Oregon. Typed manuscript.
1944. Age, length and weight of three species of Columbia
River salmon (011q0117 R911114 WA6 Q, p!orbusaa and O. ill). Oreg.
Fish Conn. Contr. 10: 157-197.
Marrs John C.
Meehan, AM= R., and Donald B. Siniff.
1962. A study of the downstream
migrations of anadromoas fishes in the Taku ::giver, Alaska, Trans. Amer,
Fish. Soc., 91(4) 1 399-i
Miller, Richard B. 1957a, Permanence and size of home territory in stream..
dwelling cutthroat trout. Jour. Fish. Res, Dd. Canada, 14(5): 687-691.
trout.
1957b. The role of competition in the mortality of hatchery
Jour, Fish, ROB. Bd. Canada, 15(1)127-450
Cakley, Arthur L. 1961. Oregon coastal salmon spawning ground surveys for
1961. Qrel. Fish Comm,, processed. rep., 10 p.
1958. Artificial and natural production of silver salmon, pfaaulmallaki t h at Minter Creeks Washington.
Wash. Dept. of Fish. Research Dull. 4: 7b Pe
Salo, Earnest C., and William Dayliff.
life histories of the steelhead
1954. TI
rainbow trout ( igizazarjagrj, zatialata) and silver salmon LigarlizmOrclu
Shapavalov, Leo, and Alan Cr. '7aft.
=LW) with special reference to IJaddell Creek* California, and recom.
mendationo regarding their management. Calif. Dept. Fish and Game, Fish
Bull. 98, 375 p.
Smoker, William A. 1953. Stream flow and silver salmon production in
western Washington. Wash. Dept. of Fish. Fish. nesearch Papers 1(1)1
5-12.
Wallis, Joe. 1961. A biological basis for stocking streams and ponds with
silver salmon. Oreg. Fish Comm., p.7ocessed rep., 16 p.
1961. Uaahington State Department
of Pisheries, 70th annual report for 1%O. 232 p.
Washington Stai.;e Department of Fisharica.
Wickett, W. Percy. 1951. The coho saloon population of Nile Creek,
Res. Bd. Canada Prog. Repts. Pacific
391 811.089.
Fish,,
Willis, Raymond A, 1954, The length of ti
that silver salmon spent before
death on the spawning grounds at Spring Creek, Wilson River, in 19510-52.
Oreg. Fish Comm. Res. Briers 5(1):1-5.
65.
Appendix Table I.
Length-Frequency Tabulation of Marked and Unmarked
Wild Silver Salmon Adults at Gnat Creek, 1956-57.
rawL;w7Teci----77------zAiir
(in Inches)
(20" and Over
M.
Unm.lj
12
Under 20"),
M.
Unm.
M.
Unm.
2
N.
Total J
2
2
1
13
1
1
14
7
2
7
2
9
15
18
6
18
6
24
16
14
16
14
16
30
17
10
34
10
34
44
18
5
26
5
26
31
19
2
5
2
5
?
20
3
3
3
21
1
1
1
22
3
2
5
5
23
1
0
1
1
24
3
1
4
4
25
5
2
7
7
26
5
6
11
11
27
6
1
7
7
28
9
11
20
20
29
2
4
6
6
30
3
3
6
6
31
1
1
2
2
32
1
1
2
2
Total
14:7-/
fgiii
Unm.
Females
ii
43
58
90
--InG.---a--eariiMarkek.-
32
58
165
223(148) y
MMIN1.10111=1111
/ On 12/12/56 1 unmarked male, no length given; not listed in above tabulations.
On 12/12/56 1 unmarked fish, no sex given; not listed in above tabulations.
2/ Jacks, included in total, are listed separately in parentheses.
66.
Appendix Table II.
Fork Length
(in Inches)
Length-Frequency Tabulation of Marked and Unmarked
Wild Silver Salmon at Gnat Creek, 1957-58.
Jacks
Adult Males
(20" and Over) (Under 20")
M.
ilnm.
M.
Unm,
Total combined
Females
M.
Dine.
M.
Unm.
Total
11
1
1
1
12
2
2
2
13
3
14
2
15
6
16
3
1
4
2
0
2
7
6
7
13
8
8
8
8
is
17
11
6
11
6
17
18
6
12
6
12
18
19
5
5
5
5
10
1
1
2
0
0
3
4
2
2
20
1
1
1
21
22
1
23
2
24
3
25
2
5
26
3
27
28
6
29
30
2
31
32
Total
1
3
2
3
2
5
1
1
3
6
9
5
2
14
5
19
24
2 ,
3
6
3
8
11
8
6
10
12
18
30
5
5
6
5
la
16
2
1
7
3
9
12
3
3
i
2
2
1
1
1
19
34
included
1
1.04.
39
18
49
are listed separately in
122
parentheses.
203(83) 1/
67.
Appendix Table III.
lorlc
Length
(in Inches)
Length-Frequency Tabulation of Marked and Unmarked
Wild Silver Salmon Adults at Gnat Creek, 1958-59.
Adult *lee
lacks
(20" and Over) (Under 20")
Mr.
Unm.
Unm.
Peealos
117----0;67
'Tata
Combined
Total 1/
12
2
1
2
1
3
13
1
3
1
3
4
14
3
3
3
3
6
15
2
16
2
16
18
21
21
16
21
17
2
23
2
23
25
18
1
8
1
8
9
6
6
2
4
1
1
1
1
1
1
1
3
3
3
3
3
9
9
6
19
20
2
2
2
21
22
23
0
4
4
2
1
24
25
1
1
1
3
2
6
26
3
27
4
10
2
10
6
16
28
4
1
0
3
4
4
6
29
3
2
1
4
4
6
10
30
1
1
1
1
2
2
4
0
0
1
0
1
40
119
31
32
Total
1
16
14
11
el
13
24
303rinspea;irroiiirica
trligfit additional fish with no length.
eluded.
3/ Jacks, included in total, are listed separately in parentheses.
159(92) 2/
not i;:---
68.
Appendix Table
Length-Frequency Tabulation of Marked and Unmarked
Wild Silver Salmon Adults at Gnat Creek, 1959-60.
or
ngth Adult Males
(in Inches) 41AnootEl
Jacks
(Under 20")
Females
M.
--Total
WIT
M.
Unm.
Conbined
Total
Unm.
m,
12
13
1
1
1
14
3
15
1
4
1
4
5
16
4
9
4
9
13
17
1
10
1
10
11
5
5
3
5
1
1
3
4
2
3
1
1
2
18
3
5
19
2
20
1
21
2
2
3
1
1
23
24
26
1
1
1
27
1
1
1
25
1
3
1
2
2
2
4
1
1
3
1
4
5
1
4
7
5
8
13
1
1
3
1
4
5
2
7
2
7
9
28
29
2
4
,5
6
30
1
5
6
6
1
1
1
77
102
31
32
33
Total
3
11
11
32
11
34
25
69.
Appendix Table V.
so
th
(in Inches)
Length-Frequency Tabulation of Marked and Unmarked
Wild Silver Salmon Adults at Gnat Creek. 1960-61.
A
acka
(20" and Over) (Under 20")
M.
[fire.
K.
Unm.
11
otal
emales
M.
Urn.
M.
1
Untr.
Combined
Total
1
1
1
3
12
13
2
1
2
14
2
1
2
15
5
3
5
3
8
16
6
7
6
7
13
17
4
9
4
9
13
18
4
9
4
9
1)
19
3
12
3
12
15
1
1
1
2
20
1
21
1
22
1
1
1
23
0
24
25
1
1
1
1
1
2
2
1
2
26
27
1
0
1
1
2
2
2
4
28
0
29
0
30
1
2
3
3
31
1
2
3
3
57
87
Total
3
5
26
45
1
7
30
70.
Appendix Table VI.
Pork Length
Langtb-Prequenoy Tabulation of Marked and Unmarked
Wild Silver Salmon Adults at Gnat Creek, 1961-62.
Jacks
Adult Male.
Pemales
'total
N.
Unm.
an Inotm) To and Over) Pinder 20")
K.
13
Combined
Total
Unm.
1
1
1
3
1
3
1
4
15
7
3
7
3
10
16
11
2
11
2
13
17
6
6
6
6
12
18
5
2
5
2
7
19
2
6
2
6
8
2
t
20
2
21
0
22
0
23
1
1
24
25
0
1
1
1
2
26
0
27
28
1
1
29
1
1
3
1
4
5
1
2
4
3
5
8
1
1
2
1
)
it
3o
1
1
1
31
1
1
1
32
Total
0
2
6
35
20
5
11
42.
37
79
Males
1
l,.
R R---117
2
1
D
Teta1
40
39
38
-3
2
0
2
)7
1
2
1
1
2
l
36
35
311
13
32
31
30
iii
1
2
i3
1
3
2
2
1
2
Females
D-LM
D-RM
1
RV
-I
1
1
Sex Unknown
D
0 -LM
2
3
'dotal
z
1
7
0
3
6
5
3
7
3
0
3
0
1
i5=14
29
1
1)-1,14
0
1
D
Length- Frequency Distribution of Adult Fall Chinook Salmon in
the 1960 Run at GnaL Creak Weil. by Sex and Mark.
28
27
22
Fork Length
in Inches
Appendix Table VIL