WSP00625

• File Number: 8240.200.10.B
• Description: UCRBRIP Annual Reports
• Basin: Colorado Mainstem
• Date: 1/12/1995
• Author: UCRBRIP
• Title: 1994 Annual Reports Package Part 1
• Water Supply Pro - Doc Type: Publication

COLORADO RIVER RECOVERY PROGRAM
FY 94 ANNUAL PROJECT REPORT

RECOVERY PROGRAM
PROJECT NUMBER: 25

1, Project Title: Development of a Bony tail Chub Reintroduction Plan with
Emphasis on Evaluation and Management of Non-native/Bonytail Chub
Interactions

II, Principal Investigators:
Leo Lentsch
Utah Div. Wildlife Res.
1596 West North Temple
Salt Lake City, UT 84116
801/538-4756 Fax: [phone]
"NRDOHAIN.nrdwr.LLentsch@email.
state.UT,US"

Dr. Todd Crowl
Fisheries & Wildlife
University of Utah
Logan, UT 84321
801/797-2498,
Fax: [phone]
[e-mail]

III, Project Summary: (Study Goals, Objectives and End Products)

The overall goal of this study is to determine how to best address
reintroduction of bony tail chub into the Upper Colorado River.
Objectives are to: 1) develop a bony tail chub reintroduction plan
(which will address stocking needs, facility requirements, and
essential studies for successful reintroduction); 2) determine optimum
size for stocking bony tail chub; 3) evaluate the role
nonnativefish/bonytail chub interactions on successful stocking; and
4) evaluate the role of physical conditioning of captive-reared
bony tail chub before release into upper basin rivers,

IV. study Schedule:
A. Initial year: 1992
B, Final year: 1995

V, Relationship to RIPRAP: General Recovery Program Support Action Plan
IV. Manage genetic integrity and augment or restore populations,
IV,a,5, Develop basinwide bony tail chub restoration plan and seek
Program acceptance.

VI. Accomplishment of FY 94 Tasks and Deliverables, Discussion of Initial
Findings and Shortcomings:

Summarv of Initial FindinQs:

Bony tail (300) were transported from Dexter to Utah State University
and reared under different experimental conditions. First, three
different batches of 15 fish were raised in a no-flow environment and a
medium-flow environment (.IS m/sec). These conditions were maintained
for 8 months, at which time muscle plugs were taken from the caudal
area of individual fish and analyzed for white/red muscle fibre
development, The hypothesis for this experiment is that bony tail
raised in pond environments (e.g, Dexter) will not develop the
appropriate tail musculature for successful reintroduction into a large
river system. A second set of experiments were performed to determine
habitat preferences by l-yr old bony tail , The experiment consisted of
artificial streams with simulated backwaters with variable flow
regimes, Finally, artificial streams were used to allow enumeration of
bony tail feeding preferences. Possible preferences include drift