9559

• UCREFRP Catalog Number: 9559
• Author: Martinez, A. M.
• Title: An Evaluation of Nonnative Fish Control Treatments in Ponds along the Colorado and Gunnison Rivers, 1996-2002.
• USFW Year: 2004.
• USFW - Doc Type: 18/19,
• Copyright Material: NO

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twenty-one nonnative fish species and three native fish species were collected (Table
7). Native fish represented only 1.5% of the total catch from the 191 sampled ponds.
No endangered fish were sampled.
The most abundant fish species collected was fathead minnow (11,761) followed
by green sunfish (5,509) (Table 7). Fathead minnow abundance exploded in a newly
constructed wetland at Horsethief Canyon State Wildlife Area (HTSWA) in 2001 and
accounted for 85% of all fathead minnows collected in ponds between 1996 and 2002. If
the HTSWA wetland fish data are not considered, green sunfish (5,509) was the most
abundant fish species collected during the study followed by black bullhead (1,844) and
fathead minnow (1,761).
Brook stickleback, a fish species prohibited from introduction into Colorado State
waters by CDOW regulation, was also collected and reported by the landowner to have
been stocked concurrently with a shipment of fathead minnow into a pond adjacent to
the Gunnison River. Several species, including grass carp, red shiner, creek chub,
plains killifish, yellow perch, walleye, and bluehead sucker were captured in ponds
along the Colorado River, but these species were not collected from ponds along the
Gunnison River (Tables 8, 9). Smallmouth bass and walleye were rarely collected.
Green sunfish was the most prevalent nonnative fish species and was sampled in 126
(66%) of the 191 ponds that contained fish (Table 10). Similarly, largemouth bass was
present in 82 (43%) of the 191 ponds. Green sunfish (Figures 2, 3, 4) and largemouth
bass (Figures 5, 6, 7) were most commonly collected between the towns of Palisade
and Loma where the highest concentration of riverside ponds in the study area existed.
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