Mark McKinstry, Ph.D.

U.S. Bureau of Reclamation

and

Richard Valdez, Ph.D.

SWCA

RAZORBACK SUCKER IN LAKE MEAD, 

LAKE POWELL, AND LOWER GRAND 

CANYON—WHAT’S NEW AND 

WHAT’S NEXT
1) Background on razorback sucker

2) 3 BiOps for Grand Canyon and Lake Mead

3) Overview of work in Lake Mead and Lake 

Powell—Brandon Albrecht, Ron Kegerries, 

(Bio-West) Travis Francis (USFWS)

4) Science Panel Recommendations

5) Present potential future activities in Lower GC

6) Questions and discussion—5-10 minutes

Outline
Overview Razorback Sucker

• Listed ESA 1991

• Critical Habitat 

designated 1994

• Recovery plan 1998

• Recovery goals 2002
Review of Biological Opinions for RBS

• 1995 BiOp (Reclamation, Operation of Glen Canyon 

Dam)— “sponsor a workshop, develop a management 

plan for RBS in Grand Canyon.”

• 2006 BiOp (NPS-Colorado River Management Plan)—

“...conduct surveys in the Lower Gorge-Lake Mead 

interface for spawning razorback suckers...”

• 2008 BiOp (Reclamation, Shortages and Coordinated 

Reservoir Operations)—“...examine the potential 

habitat in the lower Grand Canyon for RBS and 

institute an augmentation program in collaboration 

with FWS, if appropriate.”
What is Lower Grand Canyon?

Lava Falls (RM 179.5)

South Cove

*

*

*

Current inflow area (~RM 293)

Whitmore Wash (RM 188)

Diamond Creek (RM 226)

Full Pool Lake Mead (~RM 240)

Pearce Ferry (RM 280) *

Quartermaster (RM 260) *

Spencer Crk. (RM 246) *
Douglas and Douglas (2000): 

hybrid larvae at mouth of Havasu 

and LCR

Records of 

Razorback Suckers 

in Grand Canyon
Lake Mead

Study Area

Colorado River 

Inflow area (CRI)
Overview of RBS in Lake Mead

• 16 years of study (1996-2012)

• 92 sonic-tagged individuals in Lake Mead 

• 1,123 total individuals captured or stocked

– 710 unique individuals, 

– 413 recaptures

• 4 areas of known, established reproduction in Lake Mead (Las 

Vegas Bay, Echo Bay, Overton Arm, Colorado River Inflow)

• 412 individuals aged, 2-36 years old

• 2012 Lake-wide population estimate 596 (CI 468-786) adult fish (it 

depends on the estimate and model; the CIs range from 234-992)

• Documented population of recruiting fish in Colorado River Basin

Data courtesy Brandon Albrecht and Ron 

Kegerries, Bio-West
RBS Records From Colorado River 

Inflow Area of Lake Mead

• 2000 and 2001—larvae found

• 2008—adult in Gregg Basin (near CRI)

• 2010—3 untagged (wild) adults captured, 7 

larvae

• 2011—7 untagged (wild) adults, 8 recaps, 65 

larvae 

• 2012—13 untagged (wild) adults, 13 recaps, 12 

Larvae, 2 fish moved upstream to Quartermaster 

or beyond, 3 fish moved up past Pearce Ferry, 1 

wild fish (male, ripe) captured at Spencer Creek

Data courtesy Brandon Albrecht and Ron 

Kegerries, Bio-West
Lake Mead and CRI Habitat
65 miles

Lake Mead 

Study Area

Data courtesy Brandon Albrecht and Ron 

Kegerries, Bio-West
Piute Farms-waterfall

Neskahi Wash (LM 22)

Inflow

Lake Powell Study Area 2011-2012
Neskahi Canyon – Mile 24.5 No 

Turbidity End of 

Critical Habitat

Spencer’s Camp –

Inflow Area - Mile 38.5

Waterfall –

Mile 54
• Large stocking program for RBS upstream in 

SJR, BUT 53/148 (36%) captured without PIT 

tag (Recruitment??)

• One RBS Larvae (Reproduction)

• Age of fish 4 to19 years old

• RBS captured in Lake portion of inflow

Key Findings Lake Powell

Razorback Sucker TL (mm)

0

2

4

6

8

10

12

14

16

18

300320340360380400420440460480500520540560580600620640

Total Length (mm)

Frequency
Summary of Razorback Sucker 

Sampling in Lake Powell

2011 2012

Number of PITtagged Fish 

Captured

48 47

Number of 

Untagged Fish 

Captured

27 26

Total Number of 

Fish Captured

75 (36% untagged) 73 (36% untagged)

Number of Larvae 

Captured

1 Samples in lab—more 

than last year

* 24 Colorado pikeminnow also captured 
Lake Powell Habitat
San Juan River Waterfall 2008 vs 2011

3 fish, 45, 64, and 165 

miles miles
Science Panel 2010

• Kevin Bestgen

• Chuck McAda

• Gordon Mueller

• Dale Ryden

• Melissa Trammel

• Rich Valdez
Recommendations For the Future

(Science Panel Review of RBS in Lower Grand Canyon)

• Continue work on RBS at CRI and Lake Mead

• Is augmentation necessary?

• Use translocated wild fish (wild larvae from lake 

pop’n) if augmentation is done

• Integrate all information on fish and foodbase in LGC 

and CRI

• Expand fish surveys in LGC, esp. for RBS

– Larval and small-bodied fish study

• Potentially sonic-tag large adult RBS and release in 

Lower Grand Canyon

– Look at habitat use, movements, other fish
Proposed Future Work—2013>

• Downstream of Lava Falls/Whitmore Wash to CRI 

area

• Larval and small-bodied fish sampling

– Larval fish community (known, unknown?)

• Composition, Timing, abundance, location, periodicity of spawn

– Small-bodied fish community

• Composition, relative numbers, habitats

• Sonic telemetry (captive adult fish-’Judas’ fish)

• Trammel netting

• Continue monitoring at CRI area
Thanks
Acknowledgements

Lake Mead Workgroup