9378

• UCREFRP Catalog Number: 9378
• Author: Nesler, T. P.
• Title: Recovery of the Colorado River Endangered Fishes
• USFW Year: 2000.
• USFW - Doc Type: Biological recovery goals and criteria for Colorado pikeminnow, Humpback chub, Razorback sucker & Bonytail.
• Copyright Material: NO

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must meet an eight-year abundance trend for delisting. Six populations or
population segments: Black Rocks, Westwater Canyon, Little-Colorado-Grand
Canyon, Yampa, Cataract Canyon, and Desolation-Gray Canyons have separate
recruitment rate and size structure goals for downlisting and deli sting. The goals
for recruitment rate and size categories are based on three-year rolling averages
of annual estimates. Recruitment rate goals increase for the Yampa Canyon,
Cataract Canyon, and Desolation-Gray Canyon populations between downlisting
and delisting.

Recovery goals for razorback sucker include 2 required populations in Lake
Mojave and the middle Green River and one additional population in either the
lower Green River, Colorado-Gunnison rivers, or San Juan River to meet
downlisting requirements. One more additional razorback sucker population is
required in one of the above locations to meet delisting criteria. Abundance trend
and recruitment goals for the riverine populations require stability in the abundance
goal for 12 years for delisting. Recruitment is specified only as being natural in
origin and no quantified rate is specified. Five and 12-year abundance trend goals
are specified for the Lake Mojave population.

Recovery goals for bony tail include 2 required populations for downlisting
and 3 for deli sting. Potential populations are expected to be located in any of the
following river reaches: the Yampa-middle Green River reach from Lodore Canyon
to Split Mountain Canyon, the lower Green River between Desolation Canyon and
the Green River confluence with the Colorado River, the upper Colorado River in
Debeque Canyon and the Grand Valley, and the Moab Canyon-Professor Valley
reach of the Colorado River. Abundance goals for downlisting and delisting are
the same. Abundance trend and recruitment goals require stable or increasing
population abundance eight years for delisting. Recruitment is specified only as
being natural in origin and no quantified rate is specified.