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One pikeminnow that was captured and released at RM 183.0 on 13 April was contacted first by a LOTEK~ land-based, automated data logger located on the Gunnison River at RM 1.4 on 14 June. It was contacted five times following release from a jet boat. It was next contacted from a jet boat in the Gunnison River at RM 2.7 on 18 June and again at RM 1.4 by the land-based data logger on 19 June. It was then contacted at the confluence of the Gunnison and Colorado rivers on 23 June. After that, this fish moved downstream and was contacted at the mouth of Salt Creek in Ruby Canyon (RM 144.2). It was later contacted 15 July downstream from Westwater Canyon at RM 109. It was last contacted at RM 112 in early-August moving upstream. This upstream movement was presumed to be during the post-spawning period. The other transmitter-tagged pikeminnow was released at Pike's Bar (RM 178.8) 20 April. It was contacted four times from a jet boat and once from a land-based data logger. It was not contacted until 23 June and had moved about 2 miles upstream and was still in the 15-mile reach of the Upper Colorado River. It then moved downstream i n the Colorado River and upstream i n the Lower Gunnison River as it was recorded by the data logger at RM 1.4 in the Lower Gunnison on 27 June. On 31 July. it was located at Colorado River RM 162.2, immediately downstream from Walter Walker State Wildlife Area. On 24 July it was contacted at the head of Horsethief Canyon, RM 150.1, immediately downstream from the Loma boat landing. It then moved upstream and was last contacted 27 October near its release point, RM 178.8. Both radiotagged pikeminnow exhibited downstream movement prior to and during the presumed spawning season. CONCLUSIONS The following were concluded from this evaluation: There was no documentable evidence obtained from this evaluation to conclude that sub-adult or adult Colorado pikeminnow or other native fish used the fish passage at the GVIC Diversion Dam. Certainly, more field data needs to be collected at this site before any meaningful conclusions can be made as to the usefulness of this type of fish passage for Colorado pikeminnow and other native fishes. LITERATURE CITED Burdick, B. D., and L. R. Kaeding. 1990. Biological merits of fish passage as part of recovery of Colorado squawfish in the upper Colorado River basin. Final Report. U. S. Fish and Wildlife Service, Colorado River Fishery Project. Grand Junction, CO, USA. FLO Engineering, Inc. 1997. Concept Development Report for the Grand Valley Irrigation Company (GVIC) Diversion Dam Fish Passage Structure. USBR Contract No. 1425-6-CA-40-1730A. Hart, L. G., and R. C. Summerfelt. 1975. Surgical procedures for implanting ultrasonic transmitters into flathead catfish (Plyodictis olivaris). Transactions of the American Fisheries Society 104:56.59. 12