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I I I I I I I I I I I I I I I I I I I length of channel catfish significantly (p < 0.05) decreased and fewer large channel catfish were collected. Few changes in distribution, abundance, and size class of common carp were observed. Additional removal efforts were concentrated on a discrete eight mile reach of the San Juan River between two water diversion structures. These intensified efforts have led to seasonal declines in both channel catfish and common carp abundance and significant declines in mean size class of channel catfish. Significant reductions in distribution and abundance of large bodied non-native fishes in the San Juan River by mechanical removal may reduce negative interactions with native fishes and assist in the recovery of both the Colorado pikeminnow and razorback sucker. Research and Monitoring Translocation of humpback chub (Gila cypha) above Chute Falls, Little Colorado River Sponholtz, Pamela J.1, Dennis M. Stone I, and Kara Hilwig2 I USFWS, AZFRO-Flagstaff; 2 Northern Arizona University. In summer 2003, the Arizona Fishery Resources Office, along with personnel from the Arizona Game and Fish Department, released 283 humpback chub (HBC) into the Little Colorado River (LCR), above Chute Falls, near river kilometer 16.2. HBC were captured via baited hoop nets and seining near the confluence of the Colorado River. All translocated fish were implanted with a yellow elastomer tag near the dorsal fin insertion on the left side to identify them from downstream populations. This action was part of the December 6, 2002, Biological Opinion on the proposed experimental releases from Glen Canyon Dam and removal of nonnative fish. As a conservation measure for this project, the U.S. Bureau of Reclamation, Grand Canyon Monitoring and Research Center, arid the National Park Service agreed to relocate approximately 300,50-100 mm HBC to upstream areas of the LCR in an attempt to increase survivorship ofHBC. It is hoped that this translocation will increase HBC recruitment to adulthood by allowing them an opportunity to exploit the abundant food resources, warmer water temperatures, and reduced competition/predation by fewer large-bodied fishes associated with this area. DUling post-translocation monitoring efforts in October 2003, we captured (42) HBC during three days using baited hoopnets from river kilometer 14.5 to 16.8. Of the 42 HBC captured, 9 individuals had no elastomer tag. However, significant fading of the elastomer tag occurred in nearly all HBC captured that retained the tag. One of the larger individuals (1 43mm) was found 0.5 Ion upstream of the release site and had no visi,ble tag. This suggests either upstream movement by HBC from below Chute Falls or significant growth and subsequent loss of the elastomer tag. In addition, the largest marked individual was I 34mm, which indicates that this fish experienced at least 34mm of growth between the release date, August 1, and the monitoring date of November 1 (92 days). All HBC captured were implanted with a 134.2Khz PIT tag and released back into 13