U.S. Department of the Interior

U.S. Geological Survey

Michael D. Yard, GCMRC, FlagstaffJosh Korman, Ecometric Research

Natal Origins of Rainbow Trout:Glen Canyon and Marble Canyon
Natal Origin - Study Objective

1. Quantify extent of rainbow trout movement from Lees Fer

Canyon and LCR inflow

2. Determine factors that drive trout movement (density, foo

turbidity, HFEs, etc.)

3. Quantify extent of local reproduction below Lees Ferry.4. Estimate abundance of rainbow trout in LCR inflow reach 

Biological Opinion and ‘Trigger’

5. Continue monitoring juvenile humpback chub abundance

survival in the LCR inflow reach (BioOp/trigger)

6. Relate chub survival and growth to trout abundance and t

(critical uncertainty)
Overview of Presentation

Design of sampling and mark-recapture studyAbundance, movement, local reproductionGrowth and condition factorConclusions
Annual age-0 marki

from dam to Lees F

o Length >75 mm

o ~ 10,000 marked/yro Nov. 2011, Oct & D

 Quarterly trips for 

tag recovery by Re

o Apr, Jul, Sep, Jan

o LEES FERRY (I, -5.5 o HOUSE ROCK (II, 1o BUCK FARM (III, 38o ABOVE LCR (IVa, 6o BELOW LCR (IVb, 6

Sampling De
Name: Catch Lees Ferry Lees Ferry House Rock Buck Farm U/S LCR 

Reach #: All Reaches All I II III IVa RM: (-15.6 - 64.9) (-15.6 - 0) (-5.5 - -2.1) (17.2 - 20.6) (38.2 - 41.5) (60.2 - 61.1) Nov-11 16,440 11,485 929Apr-12 11,775 529 552 549 317 Jul-12 11,641 675 795 848 339 Sep-12 17,897 553 788 842 305 Oct-12 22,381 5,088 305Dec-12 12,490 4,254 278Jan-13 12,167 625 776 987 347 Apr-13 9,765 716 1,010 879 367 Jul-13 8,437 734 828 882 428 Sep-13 13,787 994 1,068 741 478 Oct-13 12,512 5,838 255Dec-13 8,175 5,536 310Jan-14 8,742 436 1,209 1,198 554 Apr-14 7,109 615 1,147 1,155 387 Jul-14 6,585 757 1,162 933 428 Sep-14 13,156 1,047 1,395 1,155 681 Total 193,059 32,201 9,758 10,730 10,169 4,631 

Summary of RBT Catch and PIT Rele

(Preliminary Data from Korman and Yard 20
Summary of PIT Recaptures

Name: Lees Ferry Lees Ferry House Rock Buck Farm U/S LCR D/S LReach #: All I II III IVa IVRM: (-15.6 - 0) (-5.5 - -2.1) (17.2 - 20.6) (38.2 - 41.5) (60.2 - 61.1) (63.4 - 

Nov-11 221 43

Apr-12 82 144 206 149 42

Jul-12 105 219 315 137 60

Sep-12 67 193 211 124 60Oct-12 344 41

Dec-12 173 52

Jan-13 99 201 202 132 66

Apr-13 91 255 228 133 43

Jul-13 120 200 234 135 59

Sep-13 82 178 128 126 41Oct-13 429 29

Dec-13 133 41

Jan-14 50 244 214 119 94

Apr-14 33 187 215 125 48

Jul-14 41 220 160 93 52

Sep-14

Total 1,300 976 2,041 2,113 1,273 56

Percent of Tags Recapture

(Preliminary Data from Korman and Yard 20
Proportion of Population that is Mar

Reach I

Apr12

Jul12

Sep12

Jan13

Apr13

Jul13

Sep13

Jan14

Apr14

Jul14

Sep14

0.000.010.020.030.040.050.060.07

Reach II

Apr12

Jul12

Sep12

Jan13

Apr13

Jul13

Sep13

Jan14

Apr14

Jul14

Sep14

0.000.050.100.15

Reach III

Apr12

Jul12

Sep12

Jan13

Apr13

Jul13

Sep13

Jan14

Apr14

Jul14

Sep14

0.000.050.100.150.20

Reach IVa

Apr12

Jul12

Sep12

Jan13

Apr13

Jul13

Sep13

Jan14

0.000.050.100.150.200.250.30

Reach IVb

Apr12

Jul12

Sep12

Jan13

Apr13

Jul13

Sep13

Jan14

0.00.10.20.3

Trip

Proportion of Population that is Marked

(Preliminary Data from Korman and Yard 2014. Do Not Cite.)
Abundance By Reach

Reach I

Apr12

Jul12

Sep12

Jan13

Apr13

Jul13

Sep13

Jan14

Apr14

Jul14

Sep14

1015202530

Reach II

Apr12

Jul12

Sep12

Jan13

Apr13

Jul13

Sep13

Jan14

Apr14

Jul14

Sep14

468

1012

Reach III

Apr12

Jul12

Sep12

Jan13

Apr13

Jul13

Sep13

Jan14

Apr14

Jul14

Sep14

2.02.53.03.54.0

Reach IVa

Apr12

Jul12

Sep12

Jan13

Apr13

Jul13

Sep13

0.51.01.52.0

Reach IVb

Apr12

Jul12

Sep12

Jan13

Apr13

Jul13

Sep13

0.10.20.30.40.50.60.7

Trip

Abundance ('000s per km)

(Preliminary Data from Korman and Yard 2014. Do Not Cite.)
Tag-Based Movement

All Recaptures (n=8301)

Distance between release and recapture locations (km

-10 -5 0 5 10

Lower 2.5% = -2.6 kmUpper 97.5% = 5.2 km

(Preliminary Data from Korman and Yard 20
Longer Distance Movement Among R

GC II III IVa IVb # of Recaps 

GC 2228 8 1 0 2 11 

II 13 1999 12 8 6 39 

III 1 8 2087 10 7 26 

IVa 0 0 2 1153 67 69 IVb 1 0 1 11 541 13 

Outside of 

Release 

Reach

Recapture Reach

Recaptures from Sep 2014 Trip

# of Recaps 

Outside of 

GC II III IVa IVb

Release Reac

h 

GC 214 2 1 0 1 4 

II 5 590 8 4 4 21 

III 0 3 365 4 3 10 

IVa 0 0 0 201 15 15 IVb 0 0 0 4 71 4 

Recapture Reach

Release 

Reach

(Preliminary Data from Korman and Yard 20
IVa IVb

I 0.01 0.02

II 0.14 0.05

III 0.20 0.18

Destination Reac

Source 

Reach

Estimated Percentage Movement from 

Ferry and Marble Canyon Reaches t

Reaches

(Preliminary Data from Korman and Yard 20
System-Wide Abundance Based 

Interpolation Between Reaches

Apr12

Jul12

Sep12

Jan13

Apr13

Jul13

Sep13

Jan14

Apr14

Jul14

Sep14

Glen CanyonUpper Marble CanyonMid Marble CanyonLower Marble CanyonBelow LCR

Trip

Abundance (millions)

0.00.20.40.60.81.01.2

(Preliminary Data from Korman and Yard 20
(Preliminary Data from Korman and Yard 20
Reach IVa

Apr2012

Jul2012

Sep2012

Jan2013

Apr2013

Jul2013

Sep2013

Jan2014

Apr2014

Jul2014

Sep2014

0

100200300400

Year

Fork length (mm)

Local Recruitment

(Preliminary Data from Korman and Yard 20
Reach I

Apr2012

Jul2012

Sep2012

Jan2013

Apr2013

Jul2013

Sep2013

Jan2014

Apr2014

Jul2014

Sep2014

0

100200300400

Reach II

Apr2012

Jul2012

Sep2012

Jan2013

Apr2013

Jul2013

Sep2013

Jan2014

Apr2014

Jul2014

Sep2014

0

100200300400

Reach III

Apr2012

Jul2012

Sep2012

Jan2013

Apr2013

Jul2013

Sep2013

0

100200300400

Reach IVa

Apr2012

Jul2012

Sep2012

Jan2013

Apr2013

Jul2013

Sep2013

0

100200300400

Year

Fork length (mm)

(Preliminary Data from Korman and Yard 2014. Do Not Cite.)
Length-at-Age Curve

Age (yrs)

Fork length (mm)

100150200250300350

1234567

(Preliminary Data from Korman and Yard 2014. Do Not Cite.)
Reach I

0

1020

Reach II

0

1020

Reach III

0

1020

Apr12-Jul12

Jul12-Sep12

Sep12-Jan13

Jan13-Apr13

Apr13-Jul13

Jul13-Sep13

Sep13-Jan14

Jan14-Apr14

Apr14-Jul14

Jul14-Sep14

Reach IVa

0

1020

Reach IVb

0

1020

Apr12-Jul12

Jul12-Sep12

Sep12-Jan13

Jan13-Apr13

Apr13-Jul13

Jul13-Sep13

Sep13-Jan14

Monthly Growth (mm) for 200 mm Fish

Trends in Growth (@ 200 mm)

(Preliminar

Korman and 

Do No
Trends in Condition Factor

Reach I

0.8 0.9 1.0 1.1 1.2

Reach II

0.8 0.9 1.0 1.1 1.2

Reach III

0.8 0.9 1.0 1.1 1.2

Apr2012

Jul2012

Sep2012

Jan2013

Apr2013

Jul2013

Sep2013

Jan2014

Apr2014

Jul2014

Sep2014

Reach IVa

0.8 0.9 1.0 1.1 1.2

Reach IVb

0.8 0.9 1.0 1.1 1.2

Apr2012

Jul2012

Sep2012

Jan2013

Apr2013

Jul2013

Sep2013

Relative Condition Factor

(Preliminar

Korman and 

Do No
Conceptual Model

Lees Ferry

Marble Canyon

LCR

LCR Inflow Reach

Paria

RecruitmentSurvivalGrowthEmigration rate

Immigration/EmigratioSurvivalGrowth

Immigration/Emigration, Survival,Growth, Local Recruitment

Returning Spawners?

Local Recruitment
Sampling Des

Reaches I - IVa

o 2 nights of effort per reacho 32 250 m sites are sampleo 16 sites (2 km) are sample

(robust design section).

o Marks released in robust do IVa consists only of robust 

Reach IVb (below L

o 2.4 km long (heart isl. – cao Robust design section onlyo 5 passes of effort which inc

slow (3) passes of electrofpasses of hoop netting

n = 16

n = 16

n = 16

HOUSE ROCK (17.2-20.6 RM)
Nov11-Apr12

Size Class (mm)

90 Day Survival Rate

100 150 200 250 300

0.50.60.70.80.9
Survival and Turnover

90 Day Survival Rate

I II III IVa 

0.60.70.80.91.0

Reach

Turnover Rate

I II III IVa 

0.20.30.40.50.60.7
Trends in Growth (@ 200 mm)

Reach I

-10

0

102030 Length Weight

Reach II

-10

0

102030

Reach III

-10

0

102030

Apr12-Jul12

Jul12-Sep12

Sep12-Jan13

Jan13-Apr13

Apr13-Jul13

Jul13-Sep13

Sep13-Jan14

Jan14-Apr14

Apr14-Jul14

Jul14-Sep14

Reach IVa

-10

0

102030

Reach IVb

-10

0

102030

Apr12-Jul12

Jul12-Sep12

Sep12-Jan13

Jan13-Apr13

Apr13-Jul13

Jul13-Sep13

Monthly Growth (mm or g) for 200 mm Fish
0 50 100 150 200

0.040.050.060.070.080.09

75-125mm

Apr12

Jul12

Sep12

Oct12

Dec12

Jan13

Apr13

Jul13

Sep13

Oct13

Dec13

Jan14

Apr14

Jul14

Sep14

0 20 40 60 80 100

0.020.030.040.050.06

125-175mm

Apr12

Sep12 Jul12

Dec12Oct12

Jan13

Apr13

Jul13

Oct13 Sep13

Dec13

Jan14

Apr14

Jul14

p

20 40 60 80 100

0.020.030.040.05

175-225mm

Apr12

Jul12

Sep12

Oct12

Dec12

Jan13

Apr13 Jul13

p

Oct13

Dec13

Jan14

Apr14

Jul14

Sep

50 60 70 80 90 

0.010.020.030.040.05

225-275mm

O

Dec12

Jan13

Apr13Jul13

Sep13

Oct13

Dec13

Jan14

Apr14

Jul14

Sep14

60 80 100 120 

0.010.020.030.04

275-325mm

Jul13 Apr13

p

Oct13

Dec13

Jan14

Apr14

Jul14

Sep14

Abundance ('000s)

Capture Probability
Movement: 2012-2014 vs. 2003-20

Natal Origins (n= 4023)

-10 -5 0 5 

Lower 2.5% = -2.2 kmUpper 97.5% = 5.3 km

Mechanical Removal (n= 1564)

Distance between release and recapture locations (km)

-10 -5 0 5 

Lower 2.5% = -6.4 kmUpper 97.5% = 21.6 km
Within-Reach Movement (summa

Apr2013-Jul2013

-2 -1 0 1 2

Jul2013-Sep2013

-2 -1 0 1 

Sep2013-Jan2014

-2 -1 0 1 2

Jan2014-Apr2014

-2 -1 0 1 

Distance between Release and Recapture Locations (km)

Density
Age (yrs)

Fork length (mm)

200250300

3 4

Fast growth Apr-Jul, all re

Growth in LF Jul-Sbut not in MC
0 5 10 15 20 25

0.000.050.100.15

Abundance ('000s 

per km)

Capture Probability

IIIIIIIVIV

Capture Probability
0 200 400

-10

0

1020

Nov11-Apr12

0 200 400

-10

0

1020

Apr12-Jul12

0 200 400

-10

0

1020

Jul12-Sep12

0 200 400

-10

0

1020

Sep12-Oct12

0 200 400

-10

0

1020

Oct12-Dec12

0 200 400

-10

0

1020

Dec12-Jan13

0 200 400

-10

0

1020

Jan13-Apr13

0 200 400

-10

0

1020

Apr13-Jul13

0 200 400

-10

0

1020

Jul13-Sep13

0 200 400

-10

0

1020

Sep13-Oct13

0 200 400

-10

0

1020

Oct13-Dec13

0 200 400

-10

0

1020

Dec13-Jan14

0 

-10

0

1020

J

0 

-10

0

1020

0 

-10

0

1020

J

Size-at-Release (mm)

Observed and Predicted Monthly Growth (mm)
Growth (mm/30 days)

05

1015202530

Nov11-Apr12

Apr12-Jul12

Jul12-Sep12

Sep12-Oct12

Oct12-Dec12

Dec12-Jan13

Jan13-Apr13

Apr13-Jul13

Jul13-Sep13

Sep13-Oct13

Oct13-Dec13

Dec13-Jan14

Jan14-Apr14

Apr14-Jul14

Jul14-Sep14

Trend in Growth in Lees Ferry
Conclusions

1. Abundance

a) High abundance in Lees Ferry and Upper Marbb) Much lower abundance near LCRc) Declining abundance in upstream reaches and 

abundance at LCR reaches

2. Movement

a) Very limited movement for the vast majority of b) The small fraction of fish from upstream reach

downstream are sufficient to explain the increaabundance at the LCR
Conclusions

2. Movement (con’t)

c) Movement of trout from Lees Ferry to Marble Canyon can 

and most fish had probably emigrated before our study b

d) Recaptures show that both small (age-0) and large (older

move from Lees Ferry to Marble Canyon

e) Recent increased downstream movement may be driven 

condition of fish

f) There is local reproduction in middle and lower Marble C

variable across years. 
Conclusions

3. Growth

a) Variable over space and time. b) Fastest growth in Marble Canyon in springc) Limited growth in Marble Canyon during m

season.

d) Very limited growth in fall and winter in all 

4. Condition

a) Seasonal differences in condition.b) Declining inter-annual trend in condition in 

with biggest reduction in Lees Ferry