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compass direction) relative to the listening stations (Fig. 4). Some directional error was caused by the acoustical dampening nature of aquatic vegetation and false readings caused by signal reflection of large rip-rap. . Fish numbers 6T333, 6T357, 6T364, 6T375 and 6T555 tended to be located in the southeastern portion of the pond. This was an area characterized by patches of submerged aquatic vegetation in moderately deep (1-2 m) water, a relatively abrupt, open sandy shoreline, and woody riparian vegetation (Figs. 1 and 4). Fish numbers 6T345 and 6T666 tended to be located in the northwest portion of the pond. This was an area with little submerged vegetation, relatively shallow (< 1 m), a gently sloping shoreline with dense cattail, and woody riparian vegetation (Figs. 1 and 4). Contacts with fish numbers 6T246 and 6T444 showed little geographic pattern (Fig. 4) and 6T777 was never contacted in open water. 2004 Data. Tracking of smaller fish tagged in 2004 was performed continuously after fish were released on April 8, but results were disappointing and generally uninformative. Although data acquired during the initial days after release suggested that smaller fish were present in open water throughout the day and night and did not enter cover of the high levee during daylight, most fish appeared to become stationary within a few days post release. This was interpreted as indicating either tag loss or fish mortality. Two carcasses and body parts of a third were associated with stationary signals, and two tags were recovered. All fish were presumed expired when field studies were concluded on 05 May, and most or all likely were dead at least a week prior. Subsequent experimental investigations of tagging small bonytail in hatchery raceways resulted in mortality within 14 days for all treatments, including those fitted with caudal tags and control groups. (Mueller et al. 2004). Small bony tail clearly were more fragile than larger ones and new methods of affixing transmitters that do not harm or kill the fish must be identified if reliable telemetry data are to be acquired. Additionally, sonic tags in our situation provided only a gross approximation of open-water habitat use. Rebounded signals often were diffuse, and the number of valid coordinates was consequently reduced. Preliminary investigations indicated that Lotek radio tags utilizing nano- technology were unsatisfactory for use in the Cibola HLP because signals were weak and detection radius was shorter than 10m for a tag suspended only 1 m below the surface (Marsh and Mueller, unpublished data). Conclusion Telemetry studies at the Cibola High Levee Pond indicate that adult bony tail are active during nighttime and spend the daylight hours dormant and hidden under cover amongst large boulders. This observation is consistent with stomach contents and proportion of empty guts, which indicated the most intense feeding occurred at night (Marsh et al. 2004). Adult bony tail in Lake Mohave, a mainstream Colorado River reservoir, showed a similar spatial distribution in 6