r / f t t LS "
w
fj/
fu*le'{Y*z
I
I
'1/
'e.e
e*t"oL'
y1as5(l
U F ' P q U A RIVER
B I V E R SMALLMOUTH
5}.IALLI'IT}UTH
UMPUUA
BASS
BASS INVESTIGATION
TNVESTIGATTON
1990
t 990
Kin
K i n Daily
DaiIy
O r e g o n Department
D e p a r t m e n t oF
Oregon
o f Fish
F i s h and
a n d bJildlife
t^tildlife
CT}NTENTS
CONTENTS
I N T B O D U C T IO N
INTRODUCTION
1
S T U D Y AREA
A R E A ............................................
STUDY
1
M A T E R I A L S AND
A N D METHODS
M E T H O D S .................................
MATERIALS
1
E x p l o i t a t i o n .....................................
Exploitation
1
F i s h Movement
M o v e m e n t ....................................
Fish
J
3
P
r e d a t i o n on
o n Salmonids
Salmonids
Predation
...........................
3
RESULTS
RESULTS...............................................
4
Exploitation
Exploitation
..................................... 4
F
i s h Movement
M o v e m e n t ....................................
Fish
4
P r e d a t i o n on
o n Salmonids
Salmonids
Predation
........................... 10
10
D T S C U S S I O N ............................................ 10
DISCUSSION
10
B
E F E R E N C E S............................................ 16
REFERENCES
lb
I
T A B L E S AND
A N D FIGURES
FIGUBES
TABLES
TAgLE
TABLE
PAGE
PAGE
1.
2.
3.
FIGURE
FIGURE
1.
2.
3.
4
4.
5.
5
tl6.
7.
R e s u l t s from
f r o m the
t h e tagging
t a g g i n g of
o f smailmouth
Results
s m a 1 1 m o u t h .......
.......
b
a
s
s
o
n
t h e Umpqua
bass on the
U m p q u a River,
B i v e r , 1990.
19 9 0 .
M o v e m e n t of
o f tagged
t a g g e d smallmouth
s m a l l m o u t h bass
Movement
b a s s in
i n . ........
. .
tthe
h e Umpqua
U m p q u a River,
R i v e r , 1990.
1990.
S
i m u I a t e d results
results
Simulated
of
changes
o f regulation
regulation
c h a n g e s . ......
. ,
P
r
e
s
e
n
L
b a g limit
I i m i L 12;
1 2 ; no
n o minimum
(Present
bag
I
m i n i m u m length).
length) .
S
9
i5
IS
P
AGE
PAGE
S t u d y Areas
A r e a s on
o n the
t h e Umpqua
U m p q u a and
Study
a n d South
S o u t h ..........
2
U m p q u e Rivers.
Rivers.
Umpqua
L e n g t h s of
o f smalimouth
s m a l l m o u t h bass
b a s s tagged
Lengths
t a g g e d in
i n .........
6
i n the
t h e Umpqua
U m p q u a River,
R i v e r , 1990.
in
19 9 0 .
Effects
o f bag
b a g and
Effects
of
a n d size
s i z e restrictions
restrictions
.........
7
o n harvest
h a r v e s t and
PSD.
on
a n d PSD.
Effects
o f bag
b a g and
a n d size
Effects
of
restrictions
size
restrictions
.........
8
o n yield
yield
populalion.
on
and
a n d population.
14
M
ean w
ater
temDeratures
C o w Creek
Mean
water
temperatures
Cow
C r e e k near
n e a r . .......
.
. 11
R
iddle
Riddle
(1986-1990)
.
[ 1986-1990]
M
ean w
ater
t e m p e r a t u r e s South
Mean
water
temperatures
S o u t h Umpqua
U m p q u t s.........
.
12
River
n e a r Roseburg
River
near
F o s e b u r g (1986-1990)
[ 1 e B 6 - 19 9 0 ] .
M
ean w
ater
t e m p e r a t u r e s Umpqua
U m p q u a River
Mean
water
temperatures
R i v e r . ......... 13
n
e a r Elkton
EIkton
near
(1986-1990)
[ 1986-1 oon')
IJ
I N T R O D U CITO N
INTRODUCTION
s t u d y of
o f smailmouth
s m a l l m o u t h boss
b a s s in
i n the
t h e Umpqua
u m p q u a River
F l i v e r System
A study
s y s t e m was
w€s
initiated
i n 1987
1 9 8 ? and
a n d continued
c o n t i n u e d in
i n 1988.
1gBB.
initiated
in
R
e
s
u
l
t
s
o f that
that
Results of
w o r k were
w e r e reported
r e p o r t e d in
p r o g r e s s report.
work
i n aa progress
report.
T h e study
wes
s t u d y was
The
ccontinued
ontinued
i n 1990
19 9 0 after
after
o n e - y e a r lapse.
in
aa one-year
lapse .
T
h i s report
report
This
s
u
m
m
a
r
i
z
e
s
r
e
s
u
l
t
s
w o r k conducted
o f the
t h e work
summarizes results of
c o n d u c t e d in
i n 1990.
1990.
O
bJectives
o f this
t h i s portion
portion
o f the
Objectives
of
of
t h e study
s t u d y were:
were:
1
E s t i m a t e exploitation
expJ.oitation
o f smallmouth
s m a l l m o u t h bass
b a s s in
Estimate
of
i n the
t h e Umpqua
l-.rmpqua
River.
River.
2.
2.
A s s e s s movement
m o v e m e n t of
o f smallmouth
s m a l l m o u t h bass
b a s s in
i n the
t h e Umpqua
Assess
u m p q u a River.
Fliver
3.
Obtain
additional
information
a b o u t smallmouth
Obtain
additional
information
about
bass
smallmouth
bass
p
r
e
d
a
t
i
o
n
o n salmonids
saLmonids
if
t h e effort
effort
predation on
if
the
did
d i d not
n o t interfere
interfere
w
ith
m
eeting
obJeetives
with
meeting
objectives
1 and
a n d 2.
Z.
1
S
T U D Y AREA
ABEA
STUDY
h l o r k cconducted
o n d u c t e d uunder
n d e r oObjectives
l4ork
bJectives
1 and
e n d 2 was
w a s confined
c o n f i n e d to
t o the
the
ssection
ection
o f the
t h e Umpqua
u m p q u e River
R i v e r between
of
b e t w e e n Kellogg
K e l l o g g (River
M i ] e 71)
?j)
I H i v e r Mile
a
n d Umpqua
u m p q u a (AM
1 0 3 ] (Figure
and
I B M 103)
1].
T h i s stream
s t r e e m section
[ F i g u r e 1).
s e c t i o n was
This
was
sselected
elected
bbecause
e c a u s e it
i t is
i s the
t h e most
m o s t accessible
and
the
Bccessible
a n d receives
receives
the
highest
intensity
highest
intensity
of
o f use
u s e by
b y bass
b a s s anglers.
anglers.
0 u r rationale
rationale
was
Our
was
t h a t it
i t would
w o u l d be
b e better
b e L t e r to
that
our
t o concentrate
concentrate
o u r limited
timited
resources
resources
tto
o o
btain
g o o d estimate
a good
obtain
a
of
estimate
o f exploitation
exploitation
o n the
t h e section
s e c t i o n of
on
of
river
w h e r e it
i t is
i s likely
likely
river
where
to
t o be
b e the
t h e highest
h i g h e s t rather
r e t h e r than
t h a n to
to
o
btain
a
l e s s reliable
reliable
estimate
for a
a larger
lerger
p a r t of
obtain
a less
estimate
for
part
o f the
the
sstream
t r e a m system.
system.
1
t n l o r k uunder
n d e r oobjective
bJective
33 wwas
e s cconducted
onducted o
Ljork
on
n the
t h e South
s o u t f r Umpqua
umpqua
R i v e r from
f r o m below
b e l o w t4inston
h l i n s t o n (AM
River
2 0 ] to
t o the
t h e mouth
m o u t h of
o f Cow
c o w Creek
creek
I n M 20)
( F i g u r e 1)
4 ? . 2 ) (Figure
CAM
11.
P
redation
i R M 47.2)
o n juvenile
f
a
1
1
Predation
on
fall
chinook
c
h
i
n
ook
Juvenile
ssalmon
a l m o n is
perticular
is a
a particular
c o n c e r n in
concern
i n this
t h i s area.
drets.
A downstream
downsEream
migrant
t r a p is
i s operated
o p e r a t e d on
o n lower
l o w e r Cow
c o w Creek
migrant
trap
c r e e k to
t o monitor
m o n i t o r the
the
m
a g n i t u d e and
a n d timing
t i m i n g of
o f the
magnitude
t h e smolt
s m o f t migration.
migration.
.
M A T E R I A L S AND
A N D METHODS
MATERIALS
METHODS
Exploitetion
Exploitation
stock-size
s m a l l m o u t h bass
b a s s (7
i n c h e s and
and
Stock-size
smallmouth
{ . 1 inches
Ilength)
ength)
w
e r e ccaptured
aptured
b y angling,
angling,
were
by
tagged
tagged
t a g s , and
a n d released
r e r e a s e d at
p o i n t of
a t point
tags,
o f capture.
capture.
a g e n c y abbreviation,
abbreviation,
return
e d d r e s s n and
agency
return
address,
and
over
o v e r in
i n total
totel
with
dangler
w i t h Carlin
carlin
dangler
T
a g s bore
b o r e aa number,
number,
Togs
"$5.00
" $ S . 0 0 reward".
reward',.
1
North
OOfBAY
BAYS
4B.nd
I
=
(IJ
L
g)
u-
Figure 1.
r
+
L
,f.
-i
,1JOSE
IFCURRY 1
+
Dun. Ci4y"
Myrth C
N
Cetlag.
iey!d
+'
tn
=
o
!
(('
(t'
:
g
o-
F
(l,
+t
g
o
(n
(o
q)
L
E
5
P
V,
Study Areas on the Umpqua and South
+
A
N
Umpqua Rivers.
JCK9
L
+
an
l-
(u
e.
ro
=
a
E
q
+
E
CRATCU
+
sJ
I
ndLk.
LAKE
0 Di m
7
'ç'fl
+
KLAMATH
Mfl.
_____
MAP NO. 16.4
VUMPQUA BASIN
1977
WATER RESOURCES
DEPARTMENT
tt.Je
J e r e crecorded
orded
t hthe
e d adate,
number,
te,
t atog
g nu
r m b e r , f fish
ish
l length,
ength,
aand
n d location
location
f o r each
for
e a c h fish
f i s h tagged.
tagged.
T
aggers
a c c e s s e d the
t h e river
river
Taggers
accessed
by
to
b y dri-Ftboat
driftboat
t o tag
t a g fish
fish
tthroughout
hroughout
tthe
h e study
study
section
for
section
f o r even
e v e n distribution.
distribution.
A
target
w
a s set
s e t that
target
was
at
25%
bass
that
a t least
least
o f the
2 5 - % of
t h e tagged
tagged
b o s s should
should
e
xceed
1 o inches
inches
exceed
10
in
to
the
composition
i n length
length
t o reflect
reflect
t h e size
size
composition
population
o
f the
t h e population
of
as
during
the
i987
snorkel
observed
t s s observed
during
the
19 8 ? s n o r k e l
survey.
Tegging
w
a s terminated
terminated
survey.
Tagging
was
on
tagged
fish
o n June
June 8
B so
s o that
that
tagged
fish
w
ould
b e available
availeble
would
be
to
throughout
the
of
t o anglers
anglers
throughout
t h e majority
meJority
o f the
the
fishery.
fishery.
T h e timing
The
of
was
predicted
from
timing
o f the
t h e fishery
fishery
w d s predicted
f r o m the
the
1 9 8 8 creel
1988
c r e e 1 survey.
survey .
T
a g reporting
reFgrting
p o s t e d in
Tag
instructions
businesses,
instrurct
i o n s were
w e r e posted
i n local
local
br-rsinesFes,
published
at
sites,
and
in
newspaper.
e t access
access
newspaper.
sites,
a n d published
i n the
t h e local
Iocal
Anglers
w e r e asked
b e released,
Anglers
were
tags
to
but
t o leave
t a g s on
o n fish
fish
t o be
releesed,
but
a s k e d to
leeve
t o record
record
to
and
recovery
in-Formation
to
receive
a n d report
still
report
recovery
information
t o still
receive
tthe
h e reward.
reward.
T a g recovery
recovery
w e r e received
received
p e r E o n at
Tag
reports
were
in
reports
i n person
al
t h e Roseburg
Roseburg
the
Regional
Office
of
and
Begional
0ffice
o f the
t h e Department
Department
a n d by
b y mail.
mail.
Reports
Reports
were
w e r e logged
w h e n received.
l o g g e d when
received.
fInformation
nformation
about
a b o u t the
the
pro3ect
a n d the
t h e individual
given
project
and
fish
was
or
individual
w a s given
fish
o r sent
s e n t to
t o each
each
reporting
reporting
angler.
angler.
Anglers
w e r e asked
Anglers
also
aa
a l s o were
a s k e d to
t o complete
comptete
f o r m with
w i t h catch
c a t c h in-Formation
form
and
information
a
nd a
a map
m t s p showing
s h o w i n g catch
catch
llocation.
ocation.
P
ostpaid
provided
Postpaid
envelopes
envelopes
were
w e r e provided
to
t o mail
mail
rrespondents.
espondent
s.
Information
Information
requested
included
tag
requested
included
t a g number,
number,
date
caught,
Iength,
whether
date
caught,
length,
and
the
was
a n d whether
t h e fish
fish
w a s kept
k e p t or
or
rreleased.
eleased.
A
n n u a l exploitation
exploitation
Annual
to
from
t o date
d a t e was
w a s estimated
estimeted
f r o m the
t h e ratio
r a t i o 0-F
of
tagged b
a s s harvested
harvested
tagged
bass
to
tagged
bass
in
the
t o total
total
t agged bass in the
population.
population.
U e a sassumed
s u m e d t hthat
L.Je
by
a t a all
ll
t atagged
gged
bbass
a s s ccaught
aught
by
anglers
a n g l e r s were
w e r e reported.
reported.
t J e u used
s e d t hthe
e eestimate
UJe
as
stimate
oof
f eannual
nnual
eexploitation
xpl"oitati-on
t s s an
d n additional
additiona
iinput
nput
tto
o simulate
simulate
the
of
regulation
potential
t h e effects
effects
o f potential
regulation
c h a n g e s on
o n the
population
t h e bass
changes
and
b a s s population
fishery.
a n d -Fishery.
population
The
T h e population
m
o
d
e
l
i
n
g
p
r
o
g
r
d
m
u s e d was
modeling program used
1988).
w a s MOCPOP
M O C P O F(Beamesderfer,
1988J .
I Beamesderfer,
Other
m o d e l inputs
inputs
w e r e unchanged
Other
model
were
from
unchanged
f r o m what
w h e t was
w a s previously
previously
reported.
reported.
F i s h Movement
Fish
Movemen!
Recovery
location
for
Recovery
location
for
each
bass
by
e a c h reported
reported
b a s s was
w a s obtained
obtained
by
a
s
k
i
n
g
t h e angler
angler
p o i n t o-F
t o mark
m a r k the
asking the
to
on
t h e point
apture
o f ccapture
o n a detailed
deteiled
map
m a p of
o f the
t h e river
r j - v e r system.
syst em.
These
were
T h e s e locations
locations
w e r e then
then
cconverted
onverted
t o river
to
mile.
river
mi Ie.
Tagging
Tagging
and
r e c c l v e r y locations,
a n d recovery
locations,
dates,
a n d fish
fish
I e n g t h s at
dates,
and
lengths
and
a t time
t j . m e o-F
o f ttagging
agging
a
n d recapture
recapture
w e r e then
t h e n entered
entered
were
on
for
o n a€ computer
c o m p u t e r spreadsheet
spreadsheet
f o r analysis.
analysis.
P
redation
Predation
on
o n Salmonids
Salmonids
U e aattempted
ttempted
t to
o ccapture
ppredator-size
redator-siz
LJe
apture
e (>7
l>?
b a s s from
f r o m the
t h e South
S o u t h Umpqua
bass
U m p q u a River
B i v e r to
t o check
check
f o r the
t h e presence
p r e s e n c e of
o f juvenile
f e 1 1 chinook
for
chinook
J u v e n i L e fall
salmonids.
salmonids.
T h e sampling
s a m p l i n g effort
The
consisted
effort
consisted
3
inch)
smollmouth
inchJ
smal lmouth
stomach
s t o m a c h contents
content s
salmon
s a L m o n or
o r other
other
of
for
o f angling
angling
for
b a s s below
b e l o w the
t h e mouth
m o u t h of
bass
o f Cow
C o w Creek,
C r e a h dduring
u r i n g April
A p r i 1and
o n dMay
l . 1 swhen
y when
l a r g e numbers
n u m b e r s oof
f fingerling
f i n g e r l i n g salmon
large
s a l m o nwere
w e r emigrating
m i g r a t i n g downstream
downstream
t h r o u g h the
through
t h e area.
area.
T i m i n g of
Timing
o f the
t h e salmon
s a l m o n migration
m i g r a t i o n was
was
determined
ffrom
r o m ccounts
o u n t s aat
t aa downstream
determined
d o w n s t r e a m mmigrant
igrant
ttrap
r a p on
o n lower
lower
Cow
Creek.
Cow C
reek.
[ ^ J eaassessed
s s e s s e d t hthe
tential
e po
Lie
potential
for
f o r smalimouth
s m a l l m o u t h bass
p r e y on
o prey
b a s s tto
on
ssalmonids
a l m o n i d s f from
r o m tthe
h e relationship
relationship
between
bass
feeding
between bass feeding
a c t i v i t y and
activity
a n dwater
w a t e r temperature.
temperature D i s t r i c t fishery
f i s h e r y managers
District
managers
r e p o r t that
t h a t significant
s i g n i f i c a n t numbers
n u m b e r s of
report
o fjuvenile
m a y be
s a l m o n i d s may
be
J u v e n i l esalmonids
p r e s e n t in
i n stream
s t r e a m sections
s e c t i o n s inhabited
present
i n h a b i t e d by
b ysmalimouth
s m a l l m o u t h bass
b a s s from
from
March
M
a r c h 1 tthrough
h r o u g h June
J u n e 30.
30.
M e a n d daily
aily
Mean
water
w a t e r temperatures
ffor
or
temperatures
t h i s time
p e r i o d were
t i m e period
w e r eobtained
this
o b t a i n e d from
f r o mCow
C o w Creek,
C r e e k , the
t h e South
South
U
m p q u a F l iRiver,
v e r , a and
n d t hthe
e UUmpqua
Umpqua
m p q u a R i vRiver
e r f o rfort hthe
e a r s ssince
e yyears
i n c e the
the
operation
8 a l e s v i l 1 e Reservoir
o
operation
off Calesville
flows
B e s e r v o i r began
b e g a n aaffecting
ffecting
f l a w s and
and
t e m p e r a t u r e s (1986-1990)
temperatures
lot ted
T h e s e ttemperatures
These
were
emperatures
w
e r e pplotted
[ 1 9 8 6 - 19 9 0 ] .
a n d aanalyzed
n a l y z e d i nin rrelation
elation
and
to
feeding
t o smalimouth
s m a l l m o u t h bbass
ass fe
eding
aactivity
ctivity
1
.
as reported in the literature (Coble, 1975)
as reported
( Coble,
in the Iiterature
19?51 .
Ulater
tJater
temperature
r e c o r d s were
w e r e obtained
temperature
records
o b t a i n e d from
f r o m the
t h e Douglas
D o u g l e s County
County
W a t e r Resources
B e s o u r c e s DDepartment
e p a r t m e n t a and
(4ater
n d t hthe
e UU.S.
. S . Geological
G e o l o g i c a l Survey.
Survey.
R
E S U LT S
RESULTS
Exploitation
Exploitation
U e ttagged
a g g e d aa ttotal
Lie
o t a l of
o f 287
2 A ?smalimouth
s m a l l m o u t h bass
1].
Of
b a s s (Table
0f
I T e b 1 e 1)
t h e s e , 76
? 5 were
w e r e reported
r e p o r t e d caught
these,
c a u g h t by
b y anglers
a n g l e r s and
w e r e kept.
a n d 60
kept.
5 0 were
T h e eestimated
stimated
aannual
n n u a l e xexploitation
ploitation
The
rate
r a t e through
t h r o u g h the
t h e end
e n d of
of
% con
1 9 9 0 wwas
* or
a s 2 21%
1 % w i twith
h a ag 5
1990
95%
confidence
4.7%.
fidence
4.2%.
i n tinterval
erval
oof
f +
or
L e n g t h s oof
tagged a
f bass
b a s s tagged
Lengths
are
in Figure
r e shown
Forty-one
shown in
F i g u r e 2.
2.
Forty-one
p
e r c e n t of
b a s s tagged
percent
o f the
t h e bass
t a g g e d measured
m e a s u r e d 10
1 O inches
more.
i n c h e s or
o r more.
Fifty-three
p e r c e n t of
o f the
Fifty-three
percent
t h ebass
b a s s reported
r e p o r t e d by
were
b yanglers
a n g l e r s were
f i s h that
fish
t h a tmeasured
m e a s u r e d 10
1 Oinches
i n c h e s oro rmore
w h e n tagged.
m o r ewhen
tagged.
.
Model outputs from simulations 0f the effects of possible
angling regulations on population structure and harvest are
They indicate that at the current
exploitation rate, more restrictive bag and length limits
would have little effect on population size, but could
affect numbers harvested, yield in weight, and population
size structure.
Model outputs
from simulations
of the effects
of possible
angling
regulations
on population
are
strueture
and hervest
s h o w n Lin
shown
Figures
n F
igures 3
3 and
a n d 4.
4.
They indicate
that et the current
exploitation
rate,
more restrictive
bag and length
limits
would have little
effect
on population
size,
but could
affect
numbers harvested,
yield
in weight,
and population
size structure.
F i s h Movement
Fish
Movement
U e wwere
e r e a bable
l e t otooobtain
btain
Lie
of'
l location
ocation
o
f ccatch
a t c h ffor
? gtagged
o r all
a l 1 75
tagged
b a s s tthat
( T a b I e 2).
h a t were
w e r e rreported
bass
(Table
eported
( Z O % ) were
2).
Of
0 f these
t h e s e 15
were
1 S(20%)
r e p o r t e d caught
reported
c a u g h t 1 mile
m i l e or
L e s sfrom
f r o m where
o r less
w h e r e they
t h e y were
w e r e tagged.
tegged.
T h e s e f ifish
s h were
w e r e cconsidered
onsidered
These
because
sstationary
tationery
potential
b e c a u s e oof
f potential
e r r o r in
i n accurately
t s c c u r a t e l y locating
error
catch
location.
loeating
catch location.
The
T h e rremaining
emEining
(Bo%l w
5
0 bass
b a s s (80%)
e r e rreported
60
were
e p o r t e d caught
c a u g h t more
m o r e than
f r o m the
t h e n 1 mile
the
m i l e from
1
1
llocation
o c a t i o n where
w h e r e they
t h e y were
w e r e tagged.
tagged.
T
h e mean
The
m e 6 n ddistance
i s t a n c e moved
moved
w a s ?7.2
. 2 miles.
was
F o r t y - t w o percent
miles.
p e r c e n t moved
Forty-two
m o v e dupstream
58%
u p s t r e a m and
a n d58%
4
TABLE
TABLE 11
R E S U L T SFROM
RESULTS
F R O MTHE
T H E TAGGING
T A G G I N GOF
O F SMALLMOUTH
S M A L T M O U T BASS
HA S S
B
ON
O N THE
RIVER,
T H E UMPQUA
UMPOUA
R I V E R , 1990
1990
LOCAT
LOCAI
T I ON
ON
( R M 71-103)
K E I I O G G TO
T O UMPQUA
KELLOGG
U M P O U A(RN
71-103)
DATES
DATES
A P R I L 21
2 1 TO
APRIL
T O JUNE
JUNE 8
8
TYPE OF
TYPE
OF TAG
TAG
CARLIN
C A R L I N DANGLER
DANGLER
I N F O R M A T I O NON
INFORMATION
O N TAG
TAG
A G E N C Y , RETURN
R E T U R N ADDRESS;
AGENCY;
A D D R E S S , TAG
TAG
8 5 . 0 O REWARD
N
U M B E R T$5.00
NUMBER;
REI{ARD
NUMBERTAGGED
NUMBER
TAGGED
287
247
S I Z E RANGE
R A N G EOF
SIZE
O F BASS
B A S S TAGGED
TAGGED
-
7 TO
T O 16
1 6 INCHES
INCHES
(26X>
75
7 5 (26%)
NUMBERREPORTED
NUMBER
REPORTEDCAUGHT
CAUGHT
(TO D
(TO
DECEMBER
E C E M B E18)
R
18)
FISH
F I S H KEPT
KEPT
(80N)
60
6 0 (80%)
FISH RELEASED
RELEASED
(20X'
15
1
5 (20%)
E S T I M A T E OF
ESTIMATE
O F EXPLOITATION
EXPLOITATION
9 5 X CONFIDENCE
CONFIDENCE
95%
LIMITS
LIMITS
=
=
=
60/287
60/287
=
+ OR
4.7%
OR - 4
.7%
5
-
21%
2L%
FIGUREa.
FIGURE 2. LENGTHS
LENGTHS OF
OF SMALLMOUTH
SMALLMOUTH BASS
BASS
TAGGED
THEUMPQUA
TAGGED
IN
RIVER
INTHE
UMPQUA
RIVER.
- 1990
1990
r.T.
I
Cl)
UU-
0
w
z
7
8
9
9
10
10
11
11 12
14
12 13
13 14
(|NCHES)
FORKLENGTH
FORK
(INCHES)
LENGTH
6
15
15
16
FIGURE
FIGURE 3. EFFECTS
EFFECTS OF
OF BAG
BAG AND
AND SIZE
SIZE
RESTRICTIONS
RESTRICTIONS
ON HARVEST
AND PSD*
HARVESTAND
ON
PSD*
1
1]
I
P1
51
:D1
cci
F1
0
trr
w
El
cci
I8
0
o
I
o
a
ao-
F
U,
cc
E
w
UJ
aolCN
w
UJ
e
I
1
BAG12;NO
BAG1
BAG
l2;1O'MIN
BAGl2;lCMlN
BAG
MIN
BAG5;NO
S;NOMIN
BAG
BAG5;SLOT
5;SLOT
REGULATION
REGUIATION
T
Notes:
Notes:
Ia NEST I
PSD*
P
o r Proportional
P r o p o r t ' i o n a l Stock
p e r c e n t a g e of
PSD
S t o c k Density
i s the
D e n s it y is
t h e percentage
o f stockstock' l S D or
( l inches
e n g t h bass
b a s s (7
i n c h e s and
length
a n d over)
o v e r ) that
t h a t equal
e q u a ' l or
o r exceed
e x c e e d11
I I inches
i nches
i n length.
in
I ength.
T
h e s e slot
s l o t limits
l i m i t s would
These
w o u ld require
r e q u i r e anglers
a n g l e r s to
t o release
r e l e a s e bass
bass
m e a s u r in g 10
l 0 to
t o 14
I 4 inches
i n c h e s in
measuring
i n length.
length.
7
FIGURE4.. EFFECTS
BAGAND
FIGURE
EFFECTS OF
OF BAG
AND SIZE
SIZE
RESTRICTIONS
RESTRICTIONS ON
ON YIELD
YIELD AND
AND POPULATION
POPUI.ANON
19m
1800 IJJ
w
a
N
17m N
Co
a
1600z
cC]
z
z
3
o
0
o
0
0
g
1500 t14m
5
o
J
J
UJ
w
f
1300
t2,o
1100
BAG 12;NOMIN
BAG l4SLOT
5;lCIMIN
BAc 1210"MIN
1410MIN BAG
BAG
BAGS;NOMIN
5;NO MIN
BAG
S;SL,IOT
BAG5;SLOT
REGUI.ATION
REGULATION
V%
YIELD
MYELD
N
ote:
Note:
I
1m
POPUIATTON
S|ZE
POPULATION
SIZE
T
h e s e slot
s l o t limits
l i m i t s would
w o u ld require
r e q u i r' lee nanglers
These
agnt h
g .l e r s to
t o release
r e l e a s e bass
bass
m e a s u r in g 10
l 0 to
t o 14
i n c h e s in
l 4 inches
measuring
i n length.
o-
o
o-
TABLE
TABLE 22
M O V E M E NOF
T
O F TAGGED
T A G G E DSMALLMOUTH
S M A L L M O U TBASS
H
MOVEMENT
BASS
IN T
H E UMPQUA
UMPOUA
R I V E R , 1990
IN
THE
RIVERS
1990
A R E A OF
O F TAGGING
TAGGING
AREA
-
( R M 71-103)
K E T L O G GTO
T O UMPQUA
U M P O U A(RM
71-103)
KELLOGG
NUMBER
OF BASS
BASS TAGGED
NUMBER OF
TAGGED
=
=
287
287
NUMBER
RECOVERED
NUMBER RECOVERED
=75
=
75
DAYS AT
AT LARGE
LARGE
DAYS
M
INIMUM
MINIMUM
=
-3
3
t'tAxIMui{
MAXIMUM
=
=
125
MEAN
MEAN
=
= 55
55
BASS MOVEMENT
MOVET'IENT
BASS
N
O.
NO.
M I L E S MOVED
MOVED
MILES
MAX.
MAX.
MEAN
MEAN
NO MOVEMENT*
NO
MOVEMENT*
FISH
FISH
15
15
20
20
t{OVEMENT
MOVEMENT
60
60
8
800
32.7
32.7
7.20
7.20
UPSTREAM
UPSTREAM
25
25
42
42
26.O
26.0
5.44
5.44
DOT'NSTREAM
DOWNSTREAM
35
35
58
58
32.7
32.7
8.45
8.45
TOTAT
TOTAL OR
OR AVERAGE
AVERAGE
7
755
1
00
100
RATE OF
OF MOVEMENT
RATE
MOVEMENT
M I L E S PER
P E R DAY
DAY
MILES
MAX.
MAX.
MEAN
MEAN
UPSTREAM
UPSTREAM
..50
50
.L2
.12
DOT{NSTREAI'I
DOWNSTREAM
..61
61
.L7
.17
A
L L FISH
FISH
ALL
..61
61
.15
.15
* ANY MOVEMENT
I,IOVEMENT OF LESS THAN
*
THAN 1 MILE
M I L E WAS
T I A S DISREGARDED
DISREGARDED
I!]
5.85
5.85
m o v e d downstream.
downstream.
moved
T h e macimum
m a x i m u m distance
d i s t a n s B moved
m o v e d upstream
The
u p s t r € 6 m was
w6E
2 6 . 0 miles
m i r e s with
w i t h aa mean
m e a n of
26.0
miles.
o f 6.4
s.4 mires.
T h e maximum
m e x i m u m distance
distance
The
m
o v e d downstream
d o w n s t r e e m was
g . s miles.
w t s s 32.9
3 2 - ' ) miles
moved
m i r e s with
with a
a mean
m e a n 0f
o f 8.6
miles.
T
here w
n o correlations
e r e no
correlations
b e t w e e n size
There
were
between
s i z e of
o f bass
b a s s and
and
direction
o r distances
d i s t a n c e s moved.
direction
or
moved.
T a g g e d bass
b a s s that
t h a t were
w e r e reported
reported
c a u g h t were
w e r e at
Tagged
caught
a t large
f o r from
from
l a r g e for
3 to
t o 126
1 2 5 days.
days.
T
h
e
3
m
e
a n time
t i m e at
a t large
l a r g e was
The mean
w a s 66
s s days.
days.
Meximum
Maximum
rrate
ate o
f m
o v e m e n t , calculated
calculated
f o r the
t h e entire
entire
of
movement,
for
time
t i m e at
a t large,
1arge,
w
E
s
p
e
r
0
.
5
0
m
i
l
e
s
d a y upstream
u p s t r e a m and
a n d 0.61
was 0.60 miles per day
0 . 6 1 miles
p e r day
m i l e s per
day
downstream.
M e a n rate
r a t e of
downstream.
o f movement
m o v e m e n t was
w d s 0.12
p e r day
o . 1 2 miles
Mean
m i l e s per
day
u
p
s
t
r
e
a
m
,
A
.
1
?
p e r day
m i l e s per
d a y downstream
d o w n s t r e a m and
per
upstream, 0.17 miles
a n d 0.16
O . 1 S miles
m i l e s per
d
a y for
f o r all
a l I bass
b a s s that
day
t h e t moved.
moved.
Predation
o n Salmonids
Salmonids
Predation
on
Efforts
predator-size
t o capture
c a p t u r e predator-size
s m a r l m o u t h bass
f r o m the
Efforts
to
smailmouth
b a s s from
the
sSouth
o u t h Umpqua
U m p q u a River
F l i v e r when
w h e n juvenile
s a l m o n i d s were
w e r e migrating
migrating
J u v e n i l e salmonids
w
e r e unsuccessful.
unsuccessful.
were
T
he p
j . n relation
lots
o
f m
e a n daily
daily
w
a t e r temperatures
The
plots
of
mean
water
in
to
temperatures
relation
to
ssmallmouth
m a r l m o u t h bass
b a s s feeding
f e e d i n g activity
activity
s h o w that
show
t h a t bass
b e s s are
a r e actively
actively
feeding
d u r i n g about
a b o u t one-half
o n e - h a 1 f of
o f the
t h e three
t h r e e month
period
feeding
during
m o n t h time
t i m e period
t h a t juvenile
s a l m o n i d s may
p r e s e n t (Figures
m t s y be
b e present
that
salmonids
B and
S, 6
a n d 7)
?J.
Juvenile
I F i g u r e s 6,
D I S C U S S IO N
DISCUSSION
T h e estimate
estimate
o f annual
a n n u a r exploitation
exploitation
The
of
will
w i r l probably
p r o b a b l y not
not
increase
s i g n i f i c a n t r y ' F r o mfrom tag
t e g reports
r e p o r t s that
increase
significantly
t h a t come
c o m e in
through
i n through
t h e end
e n d of
o f the
t h e study
the
s t u d y year.
year.
T h e estimate
estimate
o f 21%
2 1 % is
f o r the
The
of
i s for
the
s t r e a m section
section
w h i c h receives
receives
stream
which
the
t h e heaviest
heaviest
use.
Therefore
use.
Therefore
iit
t
s h o u l d represent
represent
t h e high
h i g h end
should
the
e n d of
o f what
w h a t is
i s occurring
occurring
o n the
the
on
u m p q u a River
R i v e r as
t s s aa whole.
Umpqua
whole.
a y not
rt m
n o t represent
It
may
exploitation
represent
exploitation
o n the
t h e South
S o u t h Umpqua
u m p q u a River
B i v e r because
on
b e c a u s e of
o f major
m a j o r differences
differences
b
e t w e e n the
t h e two
t w o streams
s t r e a m s and
between
a n d their
t h e i r fisheries.
fisheries.
T h e exploitation
exploitation
r a t e of
o f 21%
2 1 % is
i s low
l o w compared
The
rate
c o m p a r e d tè
t b rates
o f 26%
26%
r a t e s of
t o 46%
4 5 % reported
reported
f o r John
J o h n Day
to
for
D a y and
a n d Brownlee
B r o w n l e e Reservoirs
Fleservoire
e t al,
a 1 , 1987,
1 9 A ? , and
IBeamesderfer,
a n d Rohrer,
R o h r e r , 1984
(Beamesderfer,
et
1 9 8 4 and
a n d 1986)
1985)
Ue
Lie
h a v e no
n o estimates
e s t i . m a t e s for
f o r streams
s t r e a m s in
have
for
i n the
t h e northwest
northwest
for
c6mparison comparison.
.
T w o opposing
o p p o s i n g factors
factors
c o u l d bias
b i e s the
Two
could
t h e estimate.
estimate.
nonOne
O n e is
i s nonrreporting
eporting
o
f
t
a
g
g
e
d
f
i
s
h
,
w
h
i
c
h
w
o
u
l
d
of tagged fish, which would cause
to
c a u s e exploitation
exproitation
to
b
e underestimated.
underestimated.
be
T h e other
o t h e r is
i s retention
retention
bass
The
of
o f tagged
t a g g e d bass
w h i c h would
w o u l d not
n o t otherwise
o t h e r w i s e be
which
b e kept.
kept.
T h i e would
w o u l d cause
This
cJuse
e
xploitation
t o be
b e overestimated.
exploitation
to
overestimated.
T h e r e is
i s some
s o m e evidence
There
e v i d e n c e of
of
this
ratter
s o u r c e of
o f bias
b i a s because
b e c a u s e anglers
this
latter
source
in
a n g l e r s interviewed
interviewed
in
1
9 8 8 rreported
eported
rreleasing
eleesing
4
6 0 / oof
o f the
t h e bass
1988
46%
b a s s caught,
c a u g h t , whereas
w h e r e a s they
they
released
o n l y 20%
Z o Y oof
o f the
t h e tagged
t a g g e d bass
released
only
b a s s reported
r e p o r t e d in
study.
i n this
t h i s study.
1
100
FIGURE5. MEAN
FIGURE
MEANWATER
WATERTEMPERATURES
TEMPERATURES
cow
GREEK
(1986-1990)
COW CREEK
NEAR
(1986-1990)
NEARRIDDLE
RTDDLE
65
ll.
;
Ill
BASS ACTIVELY FEEDING
E
I
:)
tf,
w
UJ
ao=
UJ 55
l- 55
E
IJJ
BASSFEED
FEEDSPARINGLY
BASS
SPARINGLY
w
L
>
E
:5o
BASS LETHARGIC 1
04/15
04/30 05/15
5
DATE
DATE
11
05/30
FIGURE
6.
MEANWATER
FIGURE
6. MEAN
WATER
TEMPERATURES
TEMPERATURES
SOUTH
UMPQUA
R.NEAR
NEARROSEBURG
SOUTH UMPQUA
A.
ROSEBURG
(i986-90}
(1986-90)
TL
U-
il
w
-
E
a:
:)
lI-
<L
IL
ut
o=
tu
w
65-
BASS ACTIVELY FEEDING
lE
lTJ
F
BASSFEED
FEEDSPARINGLY
SPARINGLY
BASS
55
'-55>
50
LBASS LETHARGIC7
i4.5
45ffi
03/or
03/01
03fie
03/16
II 11111111 I I III
111111111 (1111111 JUl11
111111111 liii
03/31 04/15
03/31
o4/rs 04/30
o4,lw 05/15
DATE
12
III I
05130
I 11111 I I
06114
06129
FIGURET.
MEANWATER
FIGURE
7. MEAN
TEMPERATURES
WATER
TEMPERATURES
UMPQUA
RTVER
NEAR
(1986-1990)
UMPQUA RIVER
NEAR ELKTON
ELKTON (1986-1990)
,7O
g
LL
IJJ
LU
TE
f
l-
65
E-
BASS ACTIVELY FEEDING
IU
o- 60
=
UJ
F
E 55
IJJ
F
BASS FEED SPARINGLY
5
[BASS LETHARGIC
I I I I III I I I 111111 I I I I Ii I I
03/16
03/16
I 11111 I 11111 I
03/gr
03/31
I
I III III III I I I
04/15
0/tl15
I I I
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04/30
DATE
DATE
13
t3
05/15
05/30
06/14
T h e results
results
o f population
populetion
The
of
modeling
m o d e l i n g shows
shows a
E range
r 6 n g e of
ef
rregulation
eguration
o
p
t
i
o
n
s
,
d
e
p
e
n
d
i
n
g
options, depending upon
u p o n management
m a n a g e m e n t objectives
obJectives
( T a b l e 3)
(Table
31.
A d o p t i o n of
o f the
t h e standard
s t a n d a r d statewide
Adoption
daily
statewide
o a i r y bag
bag
limit
of 5
limit
o-F'
fish,
nnot
o t mmore
o r e t than
h a n 33 oof
f w
S -Fish,
which
h i c h eexceed
x c e e d 15
1 s inches,
inches,
h a s been
proposed.
b e e n proposed.
has
M o d e r output
o u t p u t indicates
indicates
t h a t this
Model
that
t h i s would
wourd
rreduce
e d u c e the
t h e number
n u m b e r of
o f bass
b a s s harvested
h a r v e s t e d by
b y 20%
z 0 % but
b u t increase
increase
the
the
p
ercentage
o f bass
b a s s over
percentage
of
o v e r 11
1 1 inches
i n c h e s by
b y 14%.
14%.
.
T a g recovery
r e c o v e r y locations
locations
s h o w e d that
Tag
showed
t h a t most
m o s t bass
b a s s moved
moved
s
i
g
n
i
f
i
c
a
n
t
d
i
s
t
a
n
c
e
s
d
u
r
i
n
g
significant distances during the
t h e summer.
summer.
M o r e bass
b a s s moved
More
moved
d o w n s t r e a m than
t h a n upstream,
u p s t r e B m , but
downstream
b u t there
t h e r e was
w a s considerable
considerable
m o v e m e n t in
i n both
b o t h directions.
movement
directions.
T
a g returns
returns
t o date
Tag
to
d a t e have
h a v e been
been
t o o few
f e w to
p r o v i d e reliable
t o provide
too
information
reliabre
information
o n movement
m o v e m e n t during
during
on
ffall
aIl
a n d winter.
and
winter.
The m
a n a g e m e n t implication
The
management
implication
o f the
t h e information
information
o n bass
of
on
bass
m
o v e m e n t is
i s that
that
movement
bass
have
b a s s h a v e tthe
h e ccapability
apability
to
t o rapidly
rapidly
rrepopulate
epopulate
localized
areas
localized
areas
f r o m wwhich
hich
tthey
hey
m
ight
-From
might
be
be
depleted.
depleted.
T h e work
w o r k on
o n smallmouth
s m a r r m o u t h bass
predation
The
b a s s predation
o n salmonids
s a l m o n i d s was
was
on
iinconclusive.
nconcrusiver t did
d i d show
s h o w that
t h a t bass
b a s s are
It
a r e not
n o t actively
actively
feeding
dduring
uring
t the
h e eearly
ppart
a r t oof
arly
-Feeding
f the
t h e juvenile
salmonid
salmonid
Juvenile
m
lgration.
migration.
T h i s presents
p r e s e n t s the
t h e opportunity
opportunity
This
to
t o minimize
m i n i m i z e bass
bess
p
redation
b y releasing
rereasing
h a t c h e r y smolts
predation
by
hatchery
s m o l t s before
before b
a s s become
become
bass
active.
active.
14
t4
TABLE
3. SIMULATED
SIT'IULATEDRESULTS
RESULTSOF
O F REGULATION
R E G U L A T I O N CHANGES
TABLE 3.
CHANGES
( P R E S E N TB
AG L
I M I T 12;
L 2 i NO
N O MINIMUM
(PRESENT
BAG
LIMIT
M I N I T l t U t tLENGTH
L E N G T H ))
HARVEST
HARVEST
YIELD
YIELD
PSD
PSD
CATCHABLE
CATCHABLE
POPULATION
POPULATION
B A G 12;
L 2 , 10"
BAG
1 0 ' MINIMUM
} I I N I M U ! ! LN
tN
D
O T N 31%
31X
DOWN
u P 6%
6X
UP
u P 10%
UP
10x
U P 6%
UP
6I
B A G 12;
L2i
BAG
DOttN 53%
DOWN
53X
DOT{N5%
5T
DOWN
uP 34%
34X
Up
U P 9%
9X
Up
BAG L
2, 1
BAG
O-14i S
IOT
12;
10-14"
SLOT
DOIIN 40%
DOWN
40r
DOTN 45%
DOWN
45X
UP 34%
342
UP
u P 6%
6X
UP
B A G 5;
5 , NO
BAG
N O MINIMUM
M I N I M U I I I LN
LN
DOWN20%
DOWN
20t
DOI{N 15%
DOWN
15X
U P 14%
J.4X
UP
U P 3%
3%
UP
BAG 5
BAG
, 1
0 ' MINIMUM
I I I N I M U I { LN
5;
10"
LN
DOtfN
45r
DOWN 45%
D O T N 13%
DOWN
13X
U P 21%
21X
UP
u P 8%
8X
Up
BAG
5:
BAG 5:
LZ'' MINIMUM
MINIITIUM LN
LN
12"
D O W N6
3r
DOWN
63%
DOLN 25%
DOWN
25/
UP 34%
34/
UP
U P 11%
UP
lIX
B
A G 5;
BAG
5;
1 O - 1 4 i SLOT
SIOT
10-14"
DOtfN 55X
DOWN
55%
DOI{N 57%
DOWN
57r
u P 38%
38X
UP
U P 8%
Up
8U
t12"
2r U
I N I T ' t U t t LN
LN
MINIMUM
15
S
BEF
E REN
E N CT ]ES
TS
RE
FER
Beamsederfer,
e t al,
198?.
a f , 1987.
Beamsederfer,
et
Distribution,
abundance,
Enct
Distribution,
abundance,
and
p
o
p
u
l
a
t
i
o
n
d
y
n
a
m
i
c
s
o
f
n
o
r
t
h
e
r
n
population dynamics of northern squaw-Fish,
walleye,
squawfish,
wa1leye,
ssmailmouth
mal lmouth
bass,
a n d channel
channel
catfish
bass,
and
catfish
in
i n John
J o h n Day
Oey
R e s e r v o i r - 1 1985.
19 8 6 .
O
r
e
g
o n Department
Reservoir;
0epertment
o f Fish
F i s h and
Oregon
of
and
p
roject
uildlife,
FFish
ish
HResearch
esearch
D E A179-829P35097,
Ar?g-gaBp3sogz,
Liildlife,
Project
DE
A
n
n
u
a
l
P
r
o
g
r
e
s
s
R
e
p
o
r
t
t
o
Annual Progress Report to Bonneville
Power
Bonneville
Fower
ACministration,
Portland,
Administration,
Portland,
Oregon.
Oregon.
Beamesderfer,
R . C . 1988.
lgBB.
Beamesderfer,
R.C.
M O C p O p : aa flexible
flexihrle
simulator
MOCFOP:
simulator
-For
for
a
n
a
l
y
s
i
s
o
f
a
g
e
s
t
r
u
c
t
u
r
e
d
popurati.ns
analysis of age-structured populations
and
a n d stockstockrrelated
elated
functions.
functions.
oregon
Department
o f Fish
F i s h and
and
Oregon
Department
of
{ J i l d 1 i f e , P oPortland,
nt land,
O
regon.
1.Jildli-Fe,
Oregon.
C o b 1 e , D.LJ.
Coble,
D.U.
19?5.
1975.
Smallmouth
b a s s In:
In:
Smailmouth
bass
E
l
a
c
k
B
e
s
s
B
i
o
l
o
gy
a n d Management.
Menagement.
Black Bass Biology
and
Institute,
Uashington,
D.C.
Institute,
tJashington,
0.0.
Clepper,
H . fed.)
Clepper,
H.
{ed.l
Sport
Fishing
Sport
Fishing
Rohrer,
F l . L.
Rohrer-,
R.
L.
1
984.
sStudy
t u d y I:
1984.
r:
Brownlee
Beservoir
fish
Brownlee
Reservoir
fish
p
o
p
u
l
a
t
i
o
n
s
ciynemics,
community
structure
a n C the
the
populations dynamics,
community
structure
and
fishery.
fishery.
Federal
A i d in
i n Fish
F i s h Restoration
Federal
Aid
Job
Flestoration
Job
P e r f o r m a n c e Report,
F l e p o r t , Project
P r o j e c t F-73-R--5.
Performance
F-?3-R-6.
r d a h o Department
fJepartment
Idaho
o
f Fish
Fish
a n d Game,
of
and
Idaho.
G a m e , Boise,
Boise,
Idaho.
Rohrer,
R - L.
Rohrer,
R.
L.
1985.
1985.
s t u d y I:
Study
r:
Brownlee
Reservoir
Brownlee
Reservoir
fish
fish
p
o
p
u
l
a
t
i
ons
dynamics,
community
strueture
populations
dynamics,
community
structure
and
a n d the
the
ffishery.
ishery.
Federal
A i d in
i n Fish
F i s h Restoration
Federal
Aid
Job
Flestoratian
Job
Ferformance
Report,
Project
Performance
Report,
Project
F-73-R-7.
F-?3-A-?.
r d a h o Department
Department
Idaho
o
f Fish
F i s h and
a n d Game,
of
G a m e , Boise,
B o i s e , Idaho.
fda ho .
Snedecor,
Snedecor,
C.
G.
ItlethocsMethods.
tUJ.
^ .,
l , i . G.
a
n d tJ.
and
G . Cochran.
Cochran.
1967.
196?.
Statistical
Statistical
press,
T h e Iowa
l o w a State
state
university
The
University
Press,
Ames,
A m e s , Iowa.
rclwa.
l6
16