9384

• UCREFRP Catalog Number: 9384
• Author: Valdez, R. A. and R. J. Ryel.
• Title: Summary of Recovery Goals for the Four Endangered Fishes of the Colorado River Basin.
• USFW Year: 2000.
• USFW - Doc Type: Logan.
• Copyright Material: NO

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Bonytail - 2

1. Stock hatchery-reared bonytail in historic habitats to establish new populations.
2. Procure and protect habitats necessary to recover the bonytail.
3. Develop and implement agreements to regulate stocking and releases of nonative
fishes that may prey on or compete with bonytail.
4. Implement nonnative fish control, as needed, to recover the bonytail.

B. Objective, Measurable Recovery Criteria

Downlisting Criteria
Downlisting of bonytail from endangered to threatened will be considered when the
following criteria are met:

Lake Mohave
1. Maintain at least 50,000 adults for genetic viability for at least 5 years as wild
genetic refugia,

Green River Subbasin
1. A minimum estimated population of 3,500 adults for a period of 5 years, such
that:
a. the lower 95% confidence interval of the estimated population of adults
exceeds 3,500,
b. a trend in adult population point estimates for the same 5-year period that
does not decline significantly, and
c. a proportion of age 3 fish for each year that is not significantly higher than
30% or lower than 20% ofthe adult population for the same 5-year period.
2. Provide flows necessary to recover the bonytail.
3. Regulate nonnative fish releases in the main river, flood plain, and tributaries
through agreements.
4. Implement nonnative fish control, as needed, to recover the bonytail.

Upper Colorado River Subbasin
1. A minimum estimated population of 3,500 adults for a period of 5 years, such
that:
a. the lower 95% confidence interval of the estimated population of adults
exceeds 3,500,
b. a trend in adult population point estimates for the same 5 year period that
does not decline significantly, and
c. a proportion of age 3 fish for each year that is not significantly higher than
30% or lower than 20% of the adult population for the same 5-year period.
2. Provide flows necessary to recover the bonytail.
3. Regulate nonnative fish releases in the main river, flood plain, and tributaries
through agreements.
4. Implement nonnative fish control, as needed, to recover the bonytail.