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the upper Colorado and Gunnison river, long-term recapture rates were 4.7% (Burdick 2002), and Ryden (2000) also reported much higher return rates in the San Juan River. The mean RCR values for each monitoring method were lower on the Green River than on the Colorado River (Table 3). This would suggest an overall lower survival rate of individuals stocked in the Green River. Electrofishing, which was the only method used each year, produced the largest number of recaptured bonytail on both the Colorado (385) and Green (391) rivers (Table 3). In terms of raw numbers of recaptures, seining was the next most effective technique followed by fyke and hoop nets (Table 3). Electrofishing appeared to be the most effective method of recapture when considering the combination of man hours, area sampled, and range of fish sizes collected. Recaptures by stocking event 1996 - Eighteen of the bonytail stocked in the Colorado River on October 18, 1996 were collected in October and November (Table 5). Electrofishing yielded 12 bonytail and an RCR of 0.45. Only two of the stocked bonytail were collected in the backwater in which they were stocked. Most others were collected outside the mouth of this particular backwater. Subsequent sampling throughout the stocking area in spring and fall of 1997 for ISMP did not reveal any of the bonytail stocked in 1996. 1997 - Following the October 1997 stocking, only five bonytail were collected the next month (Table 5). Electrofishing yielded three of the bonytail with an RCR of 0.61. The other two fish were captured with fyke nets. One of the bonytail stocked in October 1997 (1996 cohort) was collected on June 30, 1998. This fish had grown from 116 mm to 121 nun and moved two miles upstream. 1998 - In the four months following the spring 1998 stocking, 221 bonytail were collected (Table 5). The majority (171) of these fish were collected during seining trips. Electrofishing yielded an additiona122 of the 1997 cohort (RCR=1.51) and three of the larger bonytail (1996 cohort) stocked in March 1998 were also recaptured during the April electrofishing trip (RCR=5.56). Of the large fish, one was a tuberculated ripe male (TL=31 0 mm) and one had been radio tagged. Additionally, USFWS-Grand Junction collected one of the large-sized bonytails on May 28, 1998 at RM 63.9 on the Colorado River. No monitoring was conducted on the Green or Colorado rivers after the 1998 fall stockings. Note: Catches and related catch rates based on specific cohorts of origin after the spring 1999 monitoring represent estimations based on stocked size classes. The actual cohort of origin could not be definitively determined for fish stocked after the spring 1999 monitoring due to use of coded wire tags and non-lethal sampling. This combination only reveals that recaptured fish are hatchery-reared. 1999 - In the Colorado River, a total of38 bonytail were collected between May 4 and August 12 (Table 5). Seventeen bonytail were collected during electrofishing surveys. Thirteen of these fish 10