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Razorback Sucker Research and Monitoring in the Colorado River Inflow Area of Lake Mead and the Lower Grand
Canyon, Arizona and Nevada Ron Kegerries 1, Brandon Albrecht 1, Judith M. Barkstedt 2, W. Howard Brandenberg 2,
Adam L. Barkalow 2, Steven P. Platania 2, Mark McKinstry 3, Brian Healy 5, James Stolberg 5, and Zachary Shattuck 1
(1 BIO-WEST, Inc.; 2 American Southwest Ichthyological Researchers, LLC; 3 U.S. Bureau of Reclamation; 4
U.S. National Park Service; 5 Lower Colorado River Multi-Species Conservation Program)
Colorado River inflow (CRI)
2013 2014
Netting Catch Rates (CRI)
Larval Sampling (CRI)
12
13
14
15
16
17
18
19
20
0.0
0.1
0.1
0.2
0.2
0.3
0.3
0.4
11-F
eb
15-F
eb
19-F
eb
23-F
eb
27-F
eb
3-M
ar
7-M
ar
11-M
ar
15-M
ar
19-M
ar
23-M
ar
27-M
ar
31-M
ar
4-A
pr
8-A
pr
12-A
pr
16-A
pr
20-A
pr
24-A
pr
28-A
pr
2-M
ay
6-M
ay
10-M
ay
14-M
ay
Me
an
Wa
ter
Te
mp
era
ture
(C
els
ius
)
Me
an
La
rva
l R
S C
PU
E (
#/l
igh
t-m
in)
Date
Larval CPUE Mean Temperature (C)
“Active Light Sampling”N=132
220
240
260
280
300
320
340
360
380
0
20
40
60
80
100
120
193
51
93
71
93
91
94
11
94
31
94
51
94
71
94
91
95
11
95
31
95
51
95
71
95
91
96
11
96
31
96
51
96
71
96
91
97
11
97
31
97
51
97
71
97
91
98
11
98
31
98
51
98
71
98
91
99
11
99
31
99
51
99
71
99
92
00
12
00
32
00
52
00
72
00
92
01
12
01
3
Mo
nth
En
d L
ak
e E
leva
tio
n (
me
ters
ab
ove
m
ea
n s
ea
le
ve
l)
To
tal N
um
be
r R
azo
rba
ck
Su
ck
er
Ag
ed
Year
Long-Term Monitoring (through 2014) Colorado River Inflow (through 2014)
• 2014: 1 RZ aged (age-3)• Total of 26 RZ aged at CRI
YEAR Total # # NEWWILD
# RECAP # NETS
2010 3 3 0 30
2011 15 7 8 187
2012 33 13 20 183
2013 4 1 3 70
2014 6 1 5 83*
TOTALS 61 25 36 553
Movement of tagged fish from CRI into LGC.
Overview (LGC)
• For over 20 years, RBS thought to be extirpated from the Lower Grand Canyon (LGC)
• “…undertake an effort to examine the potential of habitat in the lower Grand Canyon for the species, and institute an augmentation program in collaboration with FWS, if appropriate.” (USFWS 2007 BiOP)
• Determined suitable habitat by science panel
• Razorbacks captured in Canyon by AZGFD
Objectives• Determine RBS presence and habitat use in
LGC
– Larval and small-bodied fish community sampling within the LGC
• Assess reproduction, spawning, and distribution
– Sonic telemetry
• Explore linkages between Lake Mead and LGC
LGC Small-bodied Sampling
• 7 sampling trips per year– October, March-August 2014– Lava Falls to Pearce Ferry (RM 179-280)
• Sonic Telemetry– 9 RBS released near Lava Falls– SURs deployed every 5 miles– Active Listening
• Seining• Generalized Random TessellationStratified (GRTS) • Opportunistic Sampling
GRTS Sampling Design• Well established and used by NPS
• Ensures spatially balanced, random sampling while reducing sampler bias
• 100 RM reach was divided into 800 m segments
• S-Draw selected 40, spatially balanced, segments with an additional 10 replacements
• Sampling can occur anywhere within the segment
• Repeated sampling in each of the 40 segments each trip
LGC Small-Bodied Sampling
• No Razorback Sucker
• 4-native species
• Native dominance (P=0.0000)
• Native abundance increase Jun.-Aug.
• Native fish present throughout
• Native dominance at nearly all segments
0.0
0.5
1.0
1.5
2.0
2.5
October March April May June July August
Me
an
Ca
tch
Ra
te (#/m
2)
Sampling Trip
Mean Native Mean Nonnative
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
28
8.2
29
8.5
30
2.6
31
1.1
31
8.0
32
4.0
32
7.8
33
4.2
33
7.3
34
6.2
35
4.1
35
8.9
37
0.0
38
0.9
38
7.2
39
5.3
40
4.1
40
9.4
41
8.4
42
7.2
42
9.9
43
7.6
44
4.0
Me
an
Ca
tch
Ra
te (#/m
2)
River Kilometer
Mean Native Mean Nonnative
LGC Small-Bodied Sampling• YOY suckers
dominated early
• YOY Humpback Chub present May-Aug. (N=144)
• HC abundance increased throughout the summer
• Relatively even distribution by Aug.
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
October March April May June July August
Me
an
Ca
tch
Ra
te (#/m
2)
Sampling Trip
Mean Native
Humpback Chub
Bluehead Sucker
Flannelmouth Sucker
Speckled Dace
YOY sucker
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.18
0.20
28
8.2
29
8.5
30
2.6
31
1.1
31
8.0
32
4.0
32
7.8
33
4.2
33
7.3
34
6.2
35
4.1
35
8.9
37
0.0
38
0.9
38
7.2
39
5.3
40
4.1
40
9.4
41
8.4
42
7.2
42
9.9
43
7.6
44
4.0
Me
an
Ca
tch
Ra
te (#/m
2)
RIver Kilometer
October March April May
June July August
Telemetry
• LGC
– SURs installed every 5 RM (180-280)
– 10-Razorback Suckers released April 2013 (Separation)
– 9-Razorback Sucker implanted and released March 2014 (Lava Falls)
• CRI
– Two, wild Razorback Suckers implanted 2014
Telemetry
• 25 fish, 22,100 contacts– 8 CRI released
– 17 LGC released
• 3 fish from CRI to LGC– (2) Spencer (1) 5 miles
below Lava
– (1) LGC-CRI-LGC
• 1 wild fish from CRI to OA
• 2 fish from LCG to CRI– (1) LGC-CRI-LGC-CRI-
LGC (Spencer)– (1) LGC-CRI (Iceberg)
• Additional movement upstream and downstream within the LGC
Conclusions and Considerations• Razorback Sucker were found at the CRI for the 5th year
– Relatively young (<11 years)
• No Razorback Suckers captured during LGC small-bodied sampling in 2014– Age-0 juveniles in iceberg canyon
• Likely that movement occurring above Lava Falls– Most sonic activity from Spencer to Columbine
• GRTS sampling yielded similar species composition with higher native catch rates
• Razorback and other sucker habitat likely overlaps within the CRI and LGC with movement between the two
• Capture of other small sucker species lends hope for capturing small, wild Razorback Suckers in the future
What’s Next?• Continued CRI sampling
• LGC: 7 trips in 2015– March-Sept
– Continued telemetry
– Continued small-bodied seining
– Opportunistic adult sampling
• Explore linkages between Lake Mead and LGC
Questions??
Thank You