9699

• UCREFRP Catalog Number: 9699
• Author: Brunson, R.E., and K.D. Christopherson.
• Title: Larval razorback sucker and bonytail survival and growth in the presence of nonnative fish in the Baeser floodplain wetland of the middle Green River.
• USFW Year: 2005.
• USFW - Doc Type: Utah Division of Wildlife Resources, Vernal, Utah.
• Copyright Material: NO

nonnative species composition of this enclosure when compared to that observed in the
other enclosures. Enclosures with significant differences in nonnative species
composition included one in which larvae were introduced at a density of 4,000
larvae/acre. This enclosure had a significantly higher (Student's t, P < 0.01) composition
of adult black bullhead and adult carp and the abundance estimate represents over 19%
survival of larval razorback sucker while the replicate enclosure indicated survival at
14%. Survival of larval razorback sucker ranged from 6 to 23% in the four enclosures,
including the two control enclosures, where larvae were introduced at a density of 400
larvae/acre. These enclosures also had a significantly lower (Student's t, P < 0.01)
composition of fathead minnows than the other enclosures (Table 7).
Estimated final densities of nonnative species in each enclosure ranged from
48,705 fish acre to 209,819 fish acre in 2004. Estimated razorback sucker survival in
each enclosure indicates that higher nonnative fish densities did not negatively affect
survival in 2004 (Table 6 and Figure 2). The highest razorback sucker survival was
detected in the enclosure with the fourth highest density of nonnative fish.
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