Ongoing actions:
Reclamation would continue to support the NPS, FWS, GCMRC, and GCDAMP in
funding and implementing translocations of humpback chub into tributaries of the
Colorado River in Marble and Grand Canyons, and in monitoring the results of these
translocations, consistent with agencies’ plans and guidance (e.g., NPS Comprehensive
Fisheries Management Plan [CFMP], FWS Humpback Chub Genetics Management Plan
and Translocation Framework, and GCMRC Triennial Work Plan). Translocations allow
for opportunities to expand the area occupied by humpback chub and improve the overall
status of the species. Specifically, the following would occur:
- Humpback chub would be translocated from the lower reaches of the Little
Colorado River to areas above Chute Falls in an effort to increase growth rates
and survivorship.
- Monitoring would be conducted annually, or as needed, depending on the data
required, to determine survivability, population status, or genetic integrity of the
Havasu Creek humpback chub population. Intermittent translocations of
additional humpback chub in Havasu Creek would be conducted if the FWS and
NPS determine it is necessary to maintain genetic integrity of the population.
Reclamation would continue to fund a spring and fall population estimate annually, or at
a different frequency as deemed appropriate in consultation with FWS, using a mark
recapture based model for the Little Colorado River or the most appropriate model
developed for the current collecting techniques and data. Monitoring the chub population
allows us to determine its status (whether it is stable, increasing, or decreasing).
Reclamation would continue to fund control or removal of nonnative fish in tributaries
prior to chub translocations depending on the existing fish community in each tributary.
Reclamation, NPS, and FWS would lead any investigation into the possibility of using a
chemical piscicide, or other tools, as appropriate. Tributaries and the appropriate control
methods would be identified by the FWS, NPS, Reclamation, and GCMRC, in
consultation with the Arizona Game and Fish Department (AGFD). Depending on the
removal methods identified, additional planning and compliance may be necessary.
Removal of nonnative fishes improves the status of chub and other native fishes by
reducing competition and predation. The regulation and control of nonnative fish is a
management action identified in the Humpback Chub Recovery Goals (USFWS 2002a)
and Razorback Sucker Recovery Goals (USFWS 2002b).
Reclamation would continue to fund the FWS in maintenance of a humpback chub refuge
population at a federal hatchery (Reclamation has assisted the FWS in creating a
humpback chub refuge at the Southwestern Native Aquatic Resources and Recovery
Center [SNARRC]) or other appropriate facility by providing funding to assist in annual
maintenance (including the collection of additional humpback chub from the Little
Colorado River for this purpose). In the unlikely event of a catastrophic loss of the
Grand Canyon population of humpback chub, the refuge would provide a permanent
source of sufficient numbers of genetically representative stock for repatriating the
species.
Reclamation would continue to assist the FWS, NPS and the GCDAMP to ensure that a
stable or upward trend of humpback chub mainstem aggregations can be achieved by:
- Continuing to conduct annual monitoring of the Little Colorado River humpback
chub aggregation (e.g., juvenile chub monitoring parameters). Periodically, an
open or multistate model should be run to estimate abundance of the entire Little
Colorado River aggregation inclusive of mainstem fish.
- Supporting annual monitoring in the mainstem Colorado River to determine status
and trends of humpback chub and continuing to investigate sampling and
analytical methods to estimate abundance of chub in the mainstem.
- Conducting periodic surveys to identify additional aggregations and individual
humpback chub.
- Evaluating existing aggregations and determining drivers of these aggregations,
for example, recruitment, natal origins, spawning locations, and spawning habitat
(e.g., consider new and innovative methods such as telemetry or the Judas-fish
approach) (Kegerries et al. 2015).
- Exploring means of expanding humpback chub populations outside of the Little
Colorado River Inflow aggregation. Evaluate the feasibility of mainstem
augmentation of humpback chub that would include larval collection, rearing, and
release into the mainstem at suitable areas outside of or within existing
aggregations.
Reclamation would, through the GCDAMP, conduct disease and parasite monitoring in
humpback chub and other fishes in the mainstem Colorado. The GCMRC is currently
conducting parasite monitoring in the Little Colorado River. However, in order to better
understand how/if disease and parasites (primarily Asian tapeworm) are affecting chub
and how temperature differences may affect parasite occurrence, this work would be
expanded to include investigations of parasites in humpback chub (and surrogate fish if
necessary) in the mainstem. Ensuring adequate protection from diseases and parasites is
an identified management action needed in the Humpback Chub Recovery Goals
(USFWS 2002a) and Razorback Sucker Recovery Goals (USFWS 2002b).
New actions:
Reclamation would collaborate with the FWS, GCMRC, NPS, and the Havasupai Tribe
to conduct preliminary surveys and a feasibility study for translocation of humpback chub
into Upper Havasu Creek (above Beaver Falls). The implementation of surveys and
translocations, following the feasibility study, would be dependent on interagency
discussions, planning and compliance, and resulting outcomes of tribal consultation. As
stated above, translocations of chub into currently unoccupied habitat aid in expanding
the area occupied by the species. In addition, using a tributary to the Colorado River,
such as Upper Havasu Creek, protects translocated fish from the effects of dam
operations in the mainstem, but still allow for chub in Havasu Creek to contribute to the
mainstem population.
Reclamation would, in cooperation with the FWS, NPS, GCMRC, and AGFD, explore
and evaluate other tributaries for potential translocations.
Razorback Sucker
Ongoing actions:
Reclamation would continue to assist the NPS, FWS, and the GCDAMP in funding larval
and small-bodied fish monitoring in order to:
- Determine the extent of hybridization in flannelmouth and razorback sucker
collected in the western Grand Canyon.
- Determine habitat use and distribution of different life stages of razorback sucker
to assist in future management of flows that may help conserve the species.
Sensitive habitats to flow fluctuations could be identified and prioritized for
monitoring.
- Assess the effects of TMFs and other dam operations on razorback sucker.
Actions to benefit all native aquatic species
Ongoing actions:
Reclamation, in collaboration with the NPS and FWS, and in consultation with the
AZGFD, would investigate the possibility of renovating Bright Angel and Shinumo
Creeks with a chemical piscicide, or other tools, as appropriate. Additional planning and
compliance, and tribal consultation under Section 106 of the NHPA, would be required.
This feasibility study is outlined in the NPS CFMP (2013; see “Feasibility Study for Use
of Chemical Fish Control Methods”). The action benefits humpback chub and other
native fish by removing nonnative fish that can predate upon and compete with
humpback chub. The regulation and control of nonnative fish is a management action
identified in the Humpback Chub Recovery Goals (USFWS 2002a) and Razorback
Sucker Recovery Goals (USFWS 2002b).
Reclamation would continue to fund efforts of the GCMRC and NPS to remove brown
trout (and other nonnative species) from Bright Angel Creek and the Bright Angel Creek
Inflow reach of the Colorado River, and from other areas where new or expanded
spawning populations develop, consistent with the NPS CFMP. After 5 years of removal
efforts are completed (in 2017), an analysis of success would be conducted. Piscicides
may be considered for removal of nonnative species if determined to be appropriate and
following completion of the necessary planning and compliance actions. The regulation
and control of nonnative fish is a management action identified in the Humpback Chub
Recovery Goals (USFWS 2002a) and Razorback Sucker Recovery Goals (USFWS
2002b).
New actions:
Reclamation would explore the efficacy of a temperature control device at the dam to
respond to potential extremes in hydrological conditions due to climate conditions that
could result in nonnative fish establishment. Evaluations would be ongoing for all
current and evolving technological advances that could provide for warming and cooling
the river in both high- and low-flow discharge scenarios, and high and low reservoir
levels. These studies should include evaluating and pursuing new technologies, an
analysis of the feasibility, and a risk assessment and cost analysis for any potential
solutions. The regulation and control of nonnative fish is a management action identified
in the Humpback Chub Recovery Goals (USFWS 2002a) and Razorback Sucker
Recovery Goals (USFWS 2002b).
Reclamation would pursue means of preventing the passage of deleterious invasive
nonnative fish through Glen Canyon Dam. Because Glen Canyon Dam release
temperatures are expected to be warmer under low reservoir elevations that may occur
through the LTEMP period, options to hinder expansion of warmwater nonnative fishes
into Glen and Grand Canyons would be evaluated. Potential options to minimize or
eliminate passage through the turbine or bypass intakes, or minimize survival of
nonnative fish that pass through the dam would be assessed (flows, provide cold water,
other). While feasible options may not currently exist, technology may be developed
during the LTEMP period that could help achieve this goal. The regulation and control
of nonnative fish is a management action identified in the Humpback Chub Recovery
Goals (USFWS 2002a) and Razorback Sucker Recovery Goals (USFWS 2002b).
Reclamation would, in consultation with the FWS and AGFD, fund the NPS and
GCMRC on the completion of planning and compliance to alter the backwater slough at
River Mile (RM) 12 (commonly referred to as “Upper Slough”), making it unsuitable or
inaccessible to warmwater nonnative species that can compete with and predate upon
native fish, including humpback chub. Depending on the outcome of NPS planning and
compliance, Reclamation would implement the plan in coordination with the FWS,
AGFD, NPS and GCMRC. Additional coordination would be conducted to determine
and access any habitats that may support warmwater nonnatives. The regulation and
control of nonnative fish is a management action identified in the Humpback Chub
Recovery Goals (USFWS 2002a) and Razorback Sucker Recovery Goals (USFWS
2002b).
Reclamation would support the GCMRC and NPS in consultation with the FWS and
AGFD on the completion of planning and compliance of a plan for implementing rapid
response control efforts for newly establishing or existing deleterious invasive nonnative
species within and contiguous to the action area. Control efforts may include chemical,
mechanical, or physical methods. While feasible options may not currently exist, new
technology or innovative methods may be developed in the LTEMP period that could
help achieve this goal. Rapid response to new warmwater fish invasions may become a
more frequent need in the future with lower reservoir elevations and warmer dam
releases. The regulation and control of nonnative fish is a management action identified
in the Humpback Chub Recovery Goals (USFWS 2002a) and Razorback Sucker
Recovery Goals (USFWS 2002b).
Reclamation, will consider, in consultation with the GCDAMP, the experimental use of
TMFs to inhibit brown trout spawning and recruitment in Glen Canyon, or other
mainstem locations. Inhibiting brown trout spawning and recruitment will benefit chub
by reducing the potential for brown trout to predate upon humpback chub. The
regulation and control of nonnative fish is a management action identified in the
Humpback Chub Recovery Goals (USFWS 2002a) and Razorback Sucker Recovery
Goals (USFWS 2002b).
Southwestern willow flycatcher and Yuma Ridgway’s rail
Reclamation would partially assist in funding NPS to conduct Yuma Ridgway’s rail
surveys once every three years for the life of the LTEMP.
Reclamation would partially assist in funding NPS to conduct southwestern willow flycatcher
surveys once every two years for the life of the LTEMP.
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