9334 ‎(2)‎

• UCREFRP Catalog Number: 9334
• Author: Stickney, R. R.
• Title: Editor
• USFW Year: Series
• USFW - Doc Type: 1993
• Copyright Material: NO

APPROACH
~ The approach put forth in this plan is intended as a means of achieving the minimum viable
populations of razorback sucker and bonytail as defined by the respective recovery plans.
Currently, this plan is not intended as a means of maintaining the population sizes of the
respective species. Information used to determine stocking abundance, stocking size, stocking
location, and survival is based on the most current available data. Additional information collected
~ through monitoring efforts may contnbute to revision of this plan for a more effective approach in
the future.
Razorback sucker
~ Razorback sucker are considered a Priority 1 species for augmentation/restoration efforts (Czapla
1999). Ldcewise, the Utah stocks of razorback sucker are rated Priority 1. The Genetics
Management Plan directs the development of 25 family lots for razorback sucker propagation
efforts in the Green River sub-basin. Brood stock development began in 1989 and Ouray National
Fish Hatchery now holds the recommended number of family lots necessary to proceed with
r propagation efforts. Use of this facility and satellite locations to propagate razorback sucker in
accordance with this plan will be detailed in the Facility Operations Plan (Czapla in draft).
Razorback sucker (ir-18,500) will be stocked for five consecutive years in numbers that will allow
achievement of a minimum viable population of 5,800 fish in Year 10 (Tables 1 and 2) that has a
M muhiple age-class structure. Survival estimates used to determine number of stocked fish needed
per year are based upon monitoring of stocked razorback suckers in the San Juan River (Table 2;
Ryden 2000). Razorback sucker stocked into the Green River will be at least 300 mm in length
(Age-2+). Past monitoring efforts of stocked razorback sucker in the Colorado River and the San
Juan River may indicate greater survival in larger fish stocked (Burdick and Pfeifer 2000, Ryden
~ 2000j. Razorback sucker are expected to reach this stocking size after the third growing season.
Razorback sucker will be stocked into two reaches in the Green River: Huddle Green River and
lower Green River. The cumulative number of razorback sucker within these two reaches and
their tnbutaries will constitute the population of razorback sucker in the Green River subbasin as
~ required by the recovery goals. Each reach will be stocked with one-half the annual target
stocking objective (n-9,250). Stocking in the middle Green River will occur in the reach of River
between Jensen and Ouray (RM 302-249). Razorback sucker will be stocked into both the river
and. flooded bottomlands. Flooded bottomland stocking will occur in Above Brennan (RM 268.5)
and Johnson Bottom (RM 262.8) due to the recent documentation of increased growth of stocked
~ razorback suckers um these areas and subsequent movement into the river. These two sites are also
capable of overwintering fish. Stocking in the lower Green River will occur at both Green River
State Park (ItM 120.0) and at the mouth of the San Rafael River (RM 97.0). The river between
these two stocking sites in the lower Green River provides cobble habitat that may be suitable for
razorback sucker spawning. in addition, UDWR findings suggest that endangered species are
~ using the San Rafael for at least a portion of the year, and this river could contain one of the few
spawning azeas for razorback suckers in the lower part of the Green River basin.
~ 4