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. DRAFT . time. They often left the area and returned a week or a month later. Several fish used two different locations up to several miles apart, moving between these locations once or twice during the winter (Table 5). . During the 1986-87 winter, 6 fish (razorbacks GR-6116, GR-6119 and GR-6121 and squawfish GR-2229, GR-2227 and GR-6104) were observed moving and returning to the same locations on at least one occasion. Eight fish exhibited the same homing pattern in the 1987-88 winter including 4 razorbacks (GR-2417, OR-3231, OR-3232 and OR-3234) and 4 squawfish (OR-3236, OR-3238, OR-3245 and GR-2287). . The idea that these endangered fishes have an affinity for very localized reaches of river is also supported by observations of movement patterns from the point of release to the point of capture. Data on movements of razorback sucker and Colorado squawfish were examined to determine if the fish exhibited any tendencies to remain in or return to the area where they were captured. Any observations where a fish was located within one mile of its original capture site was noted. . During the 1986-87 winter, 2 squawfish and 5 razorbacks were located at least once within one mile of the original capture site. One squawfish (GR-6105) was first contacted 3.3 miles below it's capture site in December, and then remained wi thin 0.7 to 0.2 miles of the capture site from January through March. The other squawfish (GR-6118) was first located 1.7 miles downstream of it's capture site and slowly moved upstream through the course of the winter to within 0.9 miles of the site. . Razorback GR-6119 was located within one mile of its capture site from December through February, while GR-2417 remained near its capture site through December. Razorbacks GR-6116 and GR-6117 remained wi thin one mile of their capture site throughout the winter and razorback (GR-6121) was located within one mile of it's capture site from January through March, including one time when the fish remained at its original capture site. . . During the 1987-88 winter, 7 squawfish and 8 razorback suckers were located within one mile of their capture site at least once. squawfish GR-3422 and GR- 6365 remained near their capture sites for 2 and 3 months, respectively, then moved from the area later in the winter . One fish (GR-2287) slowly moved upstream during the winter and was located within one mile of its capture site during March. Colorado squawfish OR-3235 remained within one mile of its capture site for the entire 4 months of this study, while OR-3245 was located wi thin one mi Ie of it's capture site in late February then returned to a location downriver that it had occupied during January. The remaining two squawfish (OR-3236 and OR-3238) returned to locations within one mile of their capture sites at least twice during the study. One of these fish (OR-3236) occupied its capture si te for 2 months and remained wi thin 0.1 mile for the remainder of the study. . . Additional observations that suggest homing behavior by both razorbacks and squawfish were made during the 1987-88 winter on fish that were radio-tagged the previous winter. Five AVM radiotransmitters implanted, in 4 razorback suckers and 1 Colorado squawfish in October 1986, unexpectedly remained active through both winters of the study. The squawfish (GR-6104) was located three 27 .