8215

• UCREFRP Catalog Number: 8215
• Author: U.S. Fish and Wildlife Service.
• Title: Final Environmental Assessment
• USFW Year: 1997.
• USFW - Doc Type: Management and Control of Noonative Fish Species in Floodplain Ponds of the Upper Colorado and Gunnison Rivers.
• Copyright Material: NO

This situation is not conducive to the Recovery Program goals and objectives
to recover the endangered fishes in the Upper Colorado and Gunnison rivers.
Table 2. Summary of potential significant impacts associated with each of
the five alternatives to control nonnative fish species in
floodplain ponds along the Upper Colorado and Gunnison rivers. J
Environmental Factor Alt. 1 Alt. 2 Alt. 3 Alt. 4 Alt. 5
Ue etation and Land Use o 0 0 0 ---
Fish and Wildlife Resources o 0 0 0 0
Endan eyed Species --- +++ ++ ++ o
Historic and Cultural
Resources 0 0 0 0 0
Socio-Economic Factors o 0 0 0 ---
Indian Trust Assets o 0 0 0 0
Environmental Justice o 0 0 0 0
1/ (+) indicates some positive impact; (++) indicates a moderate positive
impact; (+++) indicates the greatest positive impact; (-) indicates some
negative impact; (--) indicates a moderate negative impact; (---) indicates
the greatest negative impact; (o) indicates no known impact.
B. Alternative 2 - Mechanical or Chemical Control of Nonnative Fish Species
From Ponds in the Floodplain. Under this alternative, mechanical (i.e.,
draining ponds, netting, electrofishing, etc.) or chemical (i.e., use of
registered piscicides) control methods would be used to remove nonnative
fish species from floodplain ponds along the Colorado and Gunnison rivers.
Mechanical or chemical control of nonnative fishes could occur in a maximum
of 25 ponds in 1997 and up to 150 ponds through the Year 2002 (Martinez and
Nesler 1996). In reality, mechanical or chemical control techniques would
be employed in about 10 ponds during 1997.
Criteria for Selecting Ponds. Ponds will be identified as to location in
the floodplain (i.e., some in 10-year and 50-year floodplains). Access for
controlling nonnative fishes would be acquired from landowners who are
willing to cooperate. One objective of the proposed control measures is to
determine if nonnative fish control in floodplain ponds within a given river
reach contribute significantly to reductions in the abundance of nonnative
fishes in riverine nursery habitats that include backwaters, embayments, and
floodplain habitats that connect with the river. Therefore, the initial
proposed control measures are considered experimental and will be carefully
evaluated.
Description of Mechanical or Chemical Control.
mechanically using large-volume pumps. The fish
trapped for removal if feasible. If the ponds were
dissolved oxygen became -low, the nonnative
Ponds may be drained
could then be seined or
pumped to the point that
fishes would die from
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