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550 biweekly until deemed necessary. We feel that the most information (e.g., the duration that fish are retained within low-velocity habitats in each reach) will be gained within the few weeks following stocking for the following two reasons: I) the numbers offish in the system may quickly decrease following stocking (e.g., fish may quickly move downstream) and/or 2) captures will quickly decrease because of natural dispersal. Three sampling trips will be completed for this experimental stocking (see Table 1). Additional trips will be completed if the number offish caught in the third trip warrants additional trips; this will be the judgement ofUDWR and the San Juan Program. If this project is funded in FY98, an additional trip will be competed in late March/early April 1998 to determine if there was any overwinter retention of the stocked YOY Colorado squawfish. A secondary objective is to determine the effects of diversion canals on Colorado squawfish movement and survival (e.g., stranding, etc.). By stocking Colorado squawfish above the upper most riursery habitat reach (Below Hogback), we will be able to determine the affect ofCudei diversion (RM 142) on YOY fish movement and survival (e.g., stranding). Field work for this objective will take place immediately following the stocking ofYOY Colorado squawfish below Hogback (the first two weeks). Methods for this objective include the placement of drift nets and or hoop nets at the entrance of the diversion and at the exit of the diversion (where the diversion exits back to the river). This will allow us to determine the relative number of Colorado squawfish entering the diversion, as well as the relative number that may be transported back to the river. Drift nets and/or hoop nets also will be placed in the river channel parallel to the diversion to determine the relative number of Colorado squawfish that proceed downstream (e.g., fish that do not enter the diversion). Experimental stocking ofiuvenile Colorado sguawfish Note: this component was covered under FY96 funds. On November 4, 1996, 100,000 juvenile sized Colorado squawfish (50-55 mm TL) obtained from Dexter National Fish Hatchery were stocked into the San Juan River. The otoliths of these fish were previously marked with a tetracycline hydrochloride (TC) stain in late May/early June 1996. Half(50,000) of these fish were stocked at the Shiprock Bridge and 50,000 at Mexican Hat. These reaches were chosen to represent two different habitat types. The two lots of fish were spray marked in October 1996 to allow field researchers to differentiate between the two stocking groups. The spray mark colors were blue and magenta and these colors should last into the spring/summer of 1997, when sacrificing fish may be necessary to determine between stocked (e.g., looking for a TC mark) vs wild. The primary objectives of this experimental stocking is to determine 1) overwinter survival of experimentally stocked age-l sized Guvenile sized) Colorado squawfish. This stocking will allow us to determine overwinter survival during a low flow winter and 2) what habitats juvenile Colorado squawfish utilize. This information is lacking in the San Juan River system as well as the entire upper basin. Very little information is available for juvenile (50 mm) Colorado squawfish and the San Juan River offers the opportunity to determine the habitat requirements of this size of Colorado squawfish and fill a data hole for this species. The first two sampling trips looking for these fish have been completed and are summarized below. 10