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

Bright Angel Creek 

Non-Native Trout Reduction

Grand Canyon National Park

Brian Healy, Clay Nelson, Emily Omana Smith, Shannon Blackbu

Ward 

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

Joe Tomelleri Illustrations
E X P E R I E N C E Y O U R 

Cooperators

•Funded by Reclamation and NPS

•Volunteers (several thousand hours)
E X P E R I E N C E Y O U R 

Project Background

 Trout initially introduced to GCNP,1920’s and 

 Greatest concentration of Brown Trout occurs in 

Angel Creek and its confluence with the Colora

 Brown Trout prey on and may compete with nat

(Whiting et al. 2014, Yard et al. 2011)

 Non-native trout control: Conservation Measur

Humpback Chub in Biological Opinion (USFW2011) 

 NPS Comprehensive Fisheries Management P

(CFMP) 2013
E X P E R I E N C E Y O U R 

Goals and Methods

 Conduct comprehensive trout reduction efforts 

and the BACI for 5 consecutive years.

 Through the reduction of non-native fish:

 Enhance and restore native fish populations in B Contribute to overall conservation of Humpback 

 Components

 Installing and operating a weir  Electrofishing for monitoring and removal in BAC Electrofishing for monitoring and removal in BAC
Monitoring Metrics

 Non-native fish:

 Overall reduction of the non-native fish population in  Changes in abundance and size structure over time

 Native fish:

 Maintain or increase native fish Evaluated by abundance,

recruitment & survival

 Adaptive Management Strategy

 Evaluation project results  Possible adaptation of methods to 

achieve desired outcomes
E X P E R I E N C E Y O U R 

Weir 

BNT 

2012-2013 NPS 176 2013-2014 NPS 13 2014-2015 NPS (As of 1/12/2015) 71 

 October 1st –M

 Checked twice 
E X P E R I E N C E Y O U R 

Project Background/Method

 Comprehensive trout reduction efforts will occu

consecutive years-as an experiment.

 Evaluate project results  Possible adaptation of methods to achieve desi

outcomes (reduced nonnatives/maintain or incrnative survival, recruitment, and abundance)

 Actions 

 Installing and operating a weir  Electrofishing for monitoring and removal in BA Electrofishing for monitoring and removal in BA

Bright Angel Creek Annua

Electrofishing Effort

 October –Febr

 8-10 people, ~
E X P E R I E N C E Y O U R 

Bright Angel Creek Annua

Electrofishing Effort
Population Estimates

Estimated Fish Density/1000m

Meters x 1000 from the Mouth to Headwaters
Population Estimates

Estimated Fish Density/1000m

Meters x 1000 from the Mouth to Headwaters

In progress
Brown Trout Size Structure

* Incomplete data for 2014-2015-
Brown Trout Size Structure

* Incomplete data for 2014-2015-
Brown Trout Size Structure

Compensatory response = shclasses* Incomplete data for 2014-2015-
Rainbow Trout Size Structu

* Incomplete data for 2014-2015-
Rainbow Trout Size Structu

* Incomplete data for 2014-2015-
Biomass of Trout Removed

985,592

124,603

640,347

79,835

438,675

0

200,000400,000600,000800,000

1,000,0001,200,000

Brown Torut Rainbow Trout

Biomass (g)

Species and Year

2012-2013 2013-201
Biomass of Trout Removed

985,592

124,603

640,347

79,835

438,675

0

200,000400,000600,000800,000

1,000,0001,200,000

Brown Torut Rainbow Trout

Biomass (g)

Species and Year

2012-2013 2013-201

35% and a 31% in biomass betweyears 1 and 2, and 2 and 3 for BNT55% reduction from year 1 to year (January 12th)
Biomass of Trout Removed

985,592

124,603

640,347

79,835

438,675

0

200,000400,000600,000800,000

1,000,0001,200,000

Brown Torut Rainbow Trout

Biomass (g)

Species and Year

2012-2013 2013-201

35% and a 12% in biomyears 1 and 2, and 2 and 44% reduction from year (January 12th)
Bluehead Sucker Size Structu

* Incomplete data for 2014-2015-
Bluehead Sucker Survival

0.5

0.55

0.6

0.65

0.7

0.75

0.8

0.85

0.9

0.95

1

Nov.2010 to Jan. 2011 Jan. 2011 to Nov.2011 NOv.2011 to Jan. 2012 Jan. 2012 to Nov. 2012 Nov

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

 2011-2015:

 52 Recaptured Trout in BAC-40 records of init

tagging location

Trout Recaptures –

05

101520253035

0 20 40 60 80 100 120 140 160 180 20

Number of Fish

River Mile of First Tagging
E X P E R I E N C E Y O U R 

Bright Angel Inflow– Electrofis Cooperative effort with GCMRC

 2013-2014 Pilot study Goal of 80% trout reduction = 10 depletions (20 

with 

 November-early December (trout aggregated) High Flow Experiment – cut removal trip in half Flooding in tributaries = muddy water Result = 2 nights/1 pass of clear water electrof

 10 total nights
Bright Angel Inflow– Electrofis
Bright Angel Inflow– Electrofis

BNT, 332

RBT, 1375

CRP, 18

FHM, 3

PKF, 1

BBH, 1

FMS, 

90

BHS, 31

HBC, 1

SPD, 1

 52 Recaps

 11 RBT tagged i 1 BBH-75 mile 1 CRP-Inflow 31 BNT tagged i 1 at 102 mile 1 at 138 mile to 
E X P E R I E N C E Y O U R 

Bright Angel Inflow– Electrofis 2014-2015 Cooperative effort with GCMRC Modified sampling

 Sampling moved to February to avoid HFE conflicts Trip is focused on areas with highest abundance

 Bright Angel Creek to Horn Creek Rapid

 A goal of 80% trout reduction = 10 depletions (

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

Beneficial Use

 To date: > 40,000 

trout to beneficial use
E X P E R I E N C E Y O U R 

Summary –

 Nearing completion of 3rd year of comprehens

reduction efforts, with 2 more years left.....

 Efficiently removing trout in BAC using electro-

 Evidence of compensatory response 

 Size class shift Decreased biomass

 Electro-fishing doesn’t appear to be impacting 

fish negatively

 Bluehead Sucker survival is high Speckled Dace abundance remains high

 Future

 Continue reduction efforts for 2 more years an

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

Phantom Ranch Boat Beach, circa 1911 

Questions? 
Bright Angel Inflow– Electrofis

0

200400600800

10001200

Above Confluence Below Confluence

66% BNT and 71% of RBT were

captured downstream of BAC

Confluence