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water during hours of darkness, presumably to feed. The spatial pattern of daytime cover use revealed a significant level of site fidelity. Most fish showed some pattern of geographic distribution at night, with most observations in a particular area of the pond, while other fish showed a random distribution. Subadult bonytail apparently occupied open water throughout the day and night and did not seek specific cover. However, all small fish are believed to have expired before the end of the field study in 2004 and their behaviors and habitat use may not have been typical. A combination of sensitivity to capture, handling, and tag attachment are believed responsible for their mortality. Methods that are not harmful to test fish should be identified and implemented to enhance reliability of future data. Selection or design ofbonytail management areas including grow-out and refugium sites should consider cover requirements for larger fish, as this may be an important limiting factor. Netting-In 2003, trammel nets were set adjacent to the high levee, up against the rip-rap just prior to sunset and a couple hours before sun rise. Over 90% of the bonytail captured were either exiting (sunset) or entering the rip-rap (dawn). To reduce the stress associated with trammel nets and handling, we attempted to capture fish using two large hoop nets that were equipped with 20-m wings. Both hoop (1.5 m) nets were double-throated and were constructed of either l-cm and or 2.5-cm meshed netting. The nets were set perpendicular to the levee, with both wings tied to the rip-rap forming a large 'V'. We believed fish found in the structure located between the wings (> 15m) had little recourse but to follow the wings and enter the throat of the trap. We were wrong. The technique only captured a total of three bonytail from four overnight sets. All three fish had become 'gilled' in the wings; two near the lead line, the other near the float line. Apparently fish were escaping by going over and under the net's wings. Bonytail proved they can easily escape hoop nets when provided sufficient time and in the absence of current. We had similarly poor results with the large minnow traps used in 2002. Tank Test-Cover preference of small bonytail was evaluated in an aquarium setting. A 114-L (30 gallon) tank was set up at Achii Hanyo and three different cover types were placed in the tanle The right hand side contained a pile of large rock (10 cm), the middle contained gravel, and the right side was a dense arrangement of plastic aquarium vegetation (Figure 13). Fourteen 7-cm bonytail were placed in the tank on 17 April. All 14 bonytail immediately hid in the rock pile where they remained overnight. The following day, 12 fish had moved into the vegetation, while two remained in the rock. When fed, fish would dart out to grab a particle and immediately return to their prospective cover. By the third day (19 April) fish moved freely throughout the aquarium unless they were disturbed or approached. When bothered they would dart and conceal themselves in cover. Gradually all 14 bonytail were using the vegetative cover instead of the rock. Snorkeling Observations-We snorkel nearly every trip, but unfortunately visibility was usually <1.5 m. Exceptionally good (> 4 m) water visibility from 26-29 July allowed us our best opportunity to observe fish. Plant growth was extensive, covering 10 to 20% of the pond's surface and possibly 40 to 60% of its volume. A dense column of spiny naiad emanated from the 10