Lees Ferry Fish Monitoring Lees Ferry Monitoring How

Lees Ferry Fish Monitoring

Lees Ferry Monitoring • How do Glen Canyon Dam operations influence the rainbow trout fishery? • Annual sampling • Electrofishing • Abundance, Size • Angler Surveys • Catch rates

Mean peak discharge = 18, 823 ± 2, 518 cfs Mean discharge = 12, 816 ± 683 cfs Modified low fluctuating flows 1991 -2010

1996 -HFE Max-45, 600 cfs Mean-15, 235 ± 529 cfs

2000 -LSSF Max-30, 900 cfs Mean- 8, 355 ± 22. 4 cfs

2003 -TSF

2004 -TSF

2004 -HFE Max-41, 900 cfs Mean- 11, 789 ± 395 cfs

2005 -TSF

2008 -HFE Max-42, 500 cfs Mean- 12, 830 ± 326 cfs

2011 -Eq. F Max-26, 200 cfs 2011 Mean- 19, 326 ± 380 cfs May-Aug Mean-24, 280 ± 257 cfs

• 1991 -2010 - 3. 1 ± 0. 52 fish/min • 2011 – 6. 9 ± 1. 35 fish/min 2000 LSSF 1996 HFE 2003 -2005 TSF 2004 HFE 2011 Eq. F 2008 HFE

Lees Ferry Standardized Monitoring Juveniles

306 -405 Lees Ferry Standardized Monitoring 306 -405 mm

Lees Ferry Standardized Monitoring >405 mm

2008 -HFE 2011 -Eq. F

Rainbow trout <152 mm 2008 HFE 2011 EQ

Rainbow trout <152 mm 2008 HFE 2008 Cohort 2011 EQ

Average total length by year

Lees Ferry Creel 1991 -2011

Low Angler Catch Rate High Angler Catch Rate 0. 4 fish/hr 1. 4 fish/hr 0. 6 fish/hr 1. 5 fish/hr

Additional species captured during sampling Total Captured Native Species Flannelmouth sucker Bluehead sucker Speckled dace 334 4 1 Brown trout Brook trout 43 12 Common carp Walleye Channel catfish Green sunfish Striped bass Smallmouth Bass Red shiner 180 12 5 3 2 2 1 Cold-water Nonnative Warm-water Nonnative

Native Fish in the Tailwater to Glen Canyon Dam

Mainstem Fish Monitoring

Rainbow trout

Rainbow trout 2000 -2011 GCD

Rainbow trout 2000 -2011 GCD

Rainbow trout 6 -fold decrease in CPUE from RM 58 63 GCD

Brown trout

Brown trout 2000 -2011 GCD

Common carp

Common carp 2000 -2011 GCD

Flannelmouth Sucker

Flannelmouth Sucker 2000 -2011 GCD

Bluehead Sucker

Bluehead Sucker GCD

Fish Management? • Vision – DFC… Desired Future Conditions – ORV… Outstanding and Remarkable Values • Compromise – Do you want big fish or a lot of fish? – Fish are not the only resource being managed for downstream of GCD • Feasibility – Fiscal – Legal – Logistical – Political

Fish Management? • Implementation (a few tools) – Add fish • Translocation • Augmentation • Stocking – Remove Fish • Mechanical Removal • Chemical Removal • Change in regulations – Habitat manipulation • Advantageous or disadvantageous for certain species – Flows – Temperature – Sediment – Food base • Feasibility

Fish Management? • • • Uncertainty/Patience – Adaptive management • Utilize best available information to design experiments to drive resource towards desired condition • Experiment • Monitor resource/resources • Analyze data and compare current resource/resources to that of desired condition • Go back to step 1 as necessary to reach desired conditions • Continue to monitor Feasibility Public Outreach – Throughout the process