BOARD00038 ‎(2)‎

• Board Meeting Date: 9/20/2006
• Description: WSP Section - San Juan River Recovery Implementation Program Document Revisions
• Board Meetings - Doc Type: Memo

Cudei project to the Hogback canal to improve upstream passage for endangered fish species in .
the river.

In addition to the Cudei diversion, other structures had the potential to impede fish movement,
particularly during low flow periods. In 2002, the Hogback diversion dam was reconstructed to
provide for improved fish passage as well as improved irrigation diversion control. The Program
funded that portion of the Hogback diversion reconstruction assignable to fish passage. The
Program also funded the construction in 2003 and operation of a selective fish passage facility at
the San Juan Generating Station diversion weir, located just downstream of Fruitland. The
Program each year provides funding to the Navajo Nation to operate the selective fish passage
facility. The Fruitland canal, located just above the confluence of the San Juan and La Plata
rivers, and the Four Comers Power Plant diversion weir also may pose an impediment to
endangered fish migration. Concerns regarding potential entrainment of endangered fish into the
diversion structures located below the confluence of the San Juan and Animas rivers are being
evaluated. In 2005, the Program funded the addition of fish screens to address entrainment of
endangered fish at the Hogback Diversion.

Non-native Fish Control

Over 40 nonnative fish species now occur in the Upper Colorado River Basin, compared to 14
native fish species. Nonnative fishes can be numerically predominant in riverine fish habitats
and communities, and negative interactions with certain warm-water nonnative fish species
(particularly sportfishes) have contributed to declines in native fish populations. The August 1,
2002 Colorado Pikeminnow (Ptychocheilus lucius), and Razorback Sucker (Xyrauchen texanus)
Recovery Goals identified predation or competition by nonnative fish species as a primary threat .
to the continued existence or the reestablishment of self-sustaining populations of these
endangered fishes.

The recovery goals require that management actions to address threats posed by nonnative fishes
be implemented in two steps: (1) develop management programs to identify the levels of
management needed to minimize or remove the threat for selected species in selected river
reaches (requirement for downlisting), and (2) implement the identified levels of nonnative fish
management (requirement for deli sting). Nonnative fish management actions conducted by the
Recovery Program are consistent with these requirements.

The goals of the Program and its participating partners, with respect to nonnative fish
management, are:

1.

Nonnative fish management will occur to attain and maintain fish communities where
populations of the endangered and other native fish species can persist and thrive, and the
recovery goals for the endangered fishes can be achieved.

Management of nonnative fishes will be conducted as needed. Implementation of an
effective nonnative fish management program is an adaptive process. As strategies are
developed and implemented, they will be evaluated and revised based on results of
research and monitoring.

Because nonnative fish species targeted for management may have sportfish value to the
angling public, the dual responsibilities of State and Federal fish and wildlife agencies to

.

2.

3.

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