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Aerial surveys using wing mounted directional antenna were conducted during each observation week to determine approximate fish locations within the river. Fish and Wildlife Service personnel obtained the fish locations by air in 1996. 1996 air surveys were usually conducted on the second or third day of the observation week. The location procedure in 1996 consisted of an upstream flight over the entire river reach followed by a downstream flight to obtain fish transmitter signals. Miller Ecological Consultants personnel obtained the fish locations by air in 1997. The 1997 air surveys were conducted on the first day of each observation week. The suspected fish locations were confirmed by repeated circling of the aircraft over suspected fish locations to confirm the transmitter signal in 1997. Ground contact surveys began immediately after the air surveys to confirm fish locations. Fish locations in the river were obtained during ground surveys by walking the shoreline or floating the river in a canoe or drift boat. After signal contact was made, the Miller Ecological crew would locate the fish position using triangulation method from positions along the shore. When ever possible the crew would obtain a strong signal and a null at a location upstream of the fish location, then the crew would move to a position directly across from the fish and obtain a second null signal. The fish position was the intersection point on the lines from the two null signals. Usually this location was verified by obtaining third null signal at a downstream location. This exact procedure was inhibited at times by fish position, topography or private property restrictions. In those instances, fish position was estimated from at least one shore or boat position. RESULTS Colorado Squawfish Colorado Squawfish were monitored in the summer of 1996 and 1997. In 1996, Colorado squaw-fish remained approximately at the locations they were tagged except for CS663 which moved approximately 7 miles upstream and 7 miles downstream at the end of the year (Figure 2). In 1997, one Colorado squawfish from 1996 was monitored and five new fish tagged in 1997 were monitored and showed the same pattern of remaining within a short river reach for most of the fish. In 1997, one fish, CS513, moved approximately 60 miles upstream from the point of initial contact in August through September 1997 (Figure 3). Colorado Squawfish #40:7810 (CS781) CS781 was captured by electrofishing at RM 94.6 on July 25, 1996. This fish was captured about ten feet offshore immediately downstream from a man-made rock outcropping. CS781 was not located by ground crews again until September 11, 1996 (Week 5) at RM 89.9. The FWS aerial surveys placed the fish between RM 91 and RM 87 during each week after it's original capture. These locations could not be confirmed by ground crews. Ground crew surveys consisted of a minimum two mile canoe float upstream and downstream of the air location. Since ground crew surveys were negative on all occasions, these air locations were not considered valid. Fish CS781 was located from the air at RM 89.8 by a member of the Miller Final Report - Colorado squawfish habitat Page 7 Miller Ecological Consultants, Inc. December 17, 1997