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Glen Canyon Dam Technical Work Group 

Agenda Item Information 

October 29, 2014

Agenda Item 

2014 Shinumo Creek Flood 

Presenter 

Jan Balsom Grand Canyon National Park 

Previous Action Taken 

N/A 

Relevant Science 

N/A 

Background Information 

Recent flash flooding in the Shinimu Creek drainage has led to dramatic changes to creek 

morphology, vegetation and physiography. Coupled with the flash flood/debris flow effects are the 

effects from the Galahad Fire. This presentation will provide a review of past translocation activities, 

current conditions in Shinimu Creek and possible next steps for ecological restoration. 

In September, NPS crews determined that only a few dace remain in the stream as a result of the 

flood. Crews went into the headwaters and surveyed the Merlin Abyss Creek area, a tributary to 

main Modred Abyss Creek and main Shinumu and found a remnant trout population in about 1/2 

mile of Merlin Abyss Creek. On October 29, crews will return and attempt to eliminate the trout 

using electroshocking gear. 
NPS Shinumo Creek Updates

Fires, Floods, and Humpback ch

Translocations

National Park ServiceU.S. Department of the InteriorGrand Canyon National Park

Jan Balsom

Deputy Chief, Science and Resource Management
Shinumo Creek- Translocation

 Valdez et al. (2000): Considered Havasu and 

Shinumo creeks priorities for translocations

 Conservation measure: 2008, 2011 Biological 

Opinions:

 Shinumo, Havasu, Bright Angel (following trout 

 Goals/Objectives established in NPS Fish 

Management Plan:

1. Primary: Develop second spawning population2. Provide rearing (grow-out) opportunities, 

augmentation of mainstem aggregations 

E X P E R I E N C E Y O U R 
Shinumo Creek - Project Histo

 Translocated 1,102 

(total) humpback chub:

 2009: 302 2010: 300 2011: 300 2013: 200

 June 2014 Chub 

Population:



≈ 125 – 190 (preliminary)

 All years represented

E X P E R I E N C E Y O U R 
Shinumo Results – 2009-2013

 Meeting Objectives for Rearing/”grow-out” Annual growth greater than Colorado River, les

LCR 2 out of 3 years (2013-14 results pending)

 Large portion of mainstem captures = transloca

fish

 No reproduction

E X P E R I E N C E Y O U R 

Comparison: Annual Growth (total length, millimetersColorado River Little Colorado 

River

Shinumo Creek

27 mm 52-58 mm 2009: 33 mm

2010: 37 mm2011: 65 mm
Galahad Point Fire – May-July 

E X P E R I E N C E Y O U R 
Fire on the Ground; Smoke in th

E X P E R I E N C E Y O U R 
 Shinumo Creek flooding (containing ash) repor

July and August

 PIT tag antenna destroyed in July September monitoring results:

 No humpback chub, bluehead sucker, rainbow t

captured

 >99% decline in fish, overall (some speckled da

found)

 Few aquatic insects Archaeological site damaged Significant channel alteration, pools filled 80-90% loss of riparian vegetation

E X P E R I E N C E Y O U R 

Galahad Point Fire – May-July 
E X P E R I E N C E Y O U R 

The new normal?
E X P E R I E N C E Y O U R 
E X P E R I E N C E Y O U R 

Bass Winter Camp at ShinumoOccupation dates 1900-1920
E X P E R I E N C E Y O U R 

BEFORE AND AFTER
E X P E R I E N C E Y O U R 

BEFORE AND AFTER
E X P E R I E N C E Y O U R 

BEFORE AND AFTER
E X P E R I E N C E Y O U R 

BEFORE AND AFTER
Continued.....

 Reconnaissance of Upper Shinumo Watershed

 Extensive flood and ash impacts Merlin Abyss Creek:

 High density of rainbow trout, 1⁄2 mile of undamag

 No fish observed elsewhere (Modred Abyss 

Creek/Shinumo Creek)

 Bluehead sucker and humpback chub = extirpat

Illustration by 
Next steps....

 Remove remaining trout in Merlin Abyss

 Action needed before spawning/dispersal

 Monitor habitat recovery (if possible):

 Aquatic macroinvertebrates Riparian vegetation Stream channel geomorphology Fish(?)

 In 3-5 years(?):

 Restore native fish community throughout water

 Humpback chub, speckled dace, bluehead sucke

E X P E R I E N C E Y O U R