CMs & Triggers

(LTEMP BO)

Kirk Young, Jessica Gwinn, Brian Healy,

Marianne Crawford
• Today:

1) Conservation Measures ‐ overview

See CMs in BO, highly abridged he

lots and lots of coordination/plann

ID’d).

2) Action Triggers – overview/Q&A

(if there is time) see details in doc!

<Handouts for both in back and pos
Conservation Measures (CM) are desig

minimize or reduce the effects of theproposed action or benefit or improve 

status of listed species. Becomes a par

proposed action.CMs address 5 listed species: Humpbac

Razorback Sucker, Southwestern Willo

Flycatcher, Yuma Ridgway’s Rail, and K

Ambersnail.
Humpback Chub ‐‐ Ongoing actions

Translocations & Translocation Monitoring:

• Marble & Grand canyon tributaries

• LCR above Chute Falls• Control or removal of nonnative fish in

tributaries prior to translocations

• Explore means to expand aggregations 

LCR; Evaluate feasibility of mainstem

augmentation
Humpback Chub Ongoing Actions cont.

Monitoring LCR:

• LCR ‐ Annual Spring and Fall population 

• LCR mainstem aggregation ‐ annual monit• LCR mainstem & LCR ‐ periodic multistate 
Humpback Chub Ongoing Actions cont.

Monitoring/Evaluating Mainstem HBC:

• Mainstem – annual aggregations monito

(status & trends, investigate pop. est. m

• Mainstem – periodic surveys to identify n

populations

• Mainstem – evaluate and determine drive

aggregations

• Mainstem – continue & expand parasite

monitoring (HBC or surrogates)
Humpback Chub Ongoing Actions cont.

Misc:

• Maintenance of HBC refuge population
Humpback Chub New Actions

• Feasibility study for translocation of HBC 

Upper Havasu Creek incollaboration wit

Havasupai Tribe

• Explore and evaluate other tributaries fo

potential translocations
Razorback Sucker Ongoing/New actions:

• Extent of hybridization in Flannelmouth 

Razorback Sucker larvae in western Gra

Canyon;

• Determine habitat use and distribution o

stages

• Assess the effects of TMFs and other da

operations
All Native Aquatic Species Ongoing Action

• Feasibility of renovating Bright Angel an

Shinumo creeks with a chemical piscicidother tools, as appropriate

• Fund removal of Brown Trout and other

nonnative species from Bright Angel Cre

inflow, and from other areas (2017 eval

5‐year effort)
All Native Aquatic Species ‐ New Actions

• Efficacy of a temperature control device 

dam

• Pursue means of preventing the passag

deleterious invasive nonnative fish throuCanyon Dam

• Alter the backwater slough at RM‐12, ma

unsuitable or inaccessible to warmwatenonnative species
All Native Aquatic Species ‐ New Actions

• Rapid response control efforts for newl

establishing or existing deleterious invanonnative species

• Consider experimental use of TMFs to in

brown trout spawning and recruitment Canyon, or other mainstem locations
Southwest Willow Flycatcher & Yuma Rail

• Partially fund Southwestern Willow Flyc

(every 2 years) and Yuma Ridgway’s Raiyears) surveys throughout the life of the 
Kanab Ambersnail Ongoing

• Ongoing monitoring of population
QUESTIONS...?
Action Triggers for the

Management of Humpback C
Previous Triggers (HFE BO):

I. RBT>760 (MS @ LCR reach)

BNT>50 (MS @ LCR reach)

HBC<7000 (ASMR)‐‐‐OR‐‐‐

II. RBT>760 (MS @ LCR reach)

BNT>50 (MS @ LCR reach)

150‐199mm HBC <910 3 of 5 years (LCR)

Water Temp < 12 C 2 Consecutive Years40‐99mm HBC decline 25% from preceding 

@ LCR reach)
Why Change?

• Mechanical Removal

o Controversial ‐ taking of life

o Expensiveo Efficacy?

• Challenged to reduce reliance on MR

Concept proposed – to use conservation ac

to bridge temporary population declines du

predators Two Tier Approach
Who’s We?

Developed by an Ad Hoc group of Grand Canyon Aqu

Biologists from USFWS, USGS‐GCMRC, AZGFD, NPS, U

(Kirk Young, David Van Haverbeke, Scott Vanderkoo

David Ward, Charles Yackulic, Mike Yard, Brian Heal

Melissa Trammel, David Rogowski, Marianne Crawfo

Submitted

November 2015
Tier 1 Trigger – Early Intervention Through Conservation A

1a. Adult HBC (LCR & Agg) point estimate <9,000 (e.g., mult

‐OR‐

1b. Recruitment of sub‐adult HBC (150‐199mm) does not e

exceed estimated adult mortality:

‐OR‐

1) LCR sub‐adult abundance 3‐year running ave

(Spring LCR estimate)

2) JCM Sub‐adult abundance 3‐year running ave

(JCM annual fall population estimate; RM 63.45
Tier 1 Response: Conservation actions implement

LCR or in the adjacent mainstem. Conservation ac

focus on increasing growth, survival and distributiin the LCR & LCR mainstem aggregation area.
Tier 2 Trigger ‐ Reduce threat using mechanical removal if

conservation actions in Tier 1 are insufficient to arrest a p

decline:

Adult HBC point abundance estimate (LCR & Agg) <7,00estimated by the currently accepted HBC population mo

Tier 2 Response:Mechanical removal will ensue and terminate if:

Predators depleted to less than 60 RBT/km for at least t

the JCM reach and immigration rate is low (the long ter

of using immigration rates as a metric still needs to be 

‐‐OR ‐‐

Adult HBC population estimates exceed 7,500 and recru

sub‐adult chub exceed adult mortality for at least two y
Caveats

• Assumes predation is 1o driver in HBC decline

• Intended to be adaptive – reviewed as neede

less than every 5 years

• Actions and triggers will need to adapt if HBC 

found to be impacted by other factors

• Re‐evaluation if a new deleterious nonnative 

species is detected in or adjacent to the LCR 

mechanical removal likely necessary
Thank You

Photo by D. Van Hav