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Division of Wildlife (CDOW). Utah Division of Wildlife Resources (UDWR) provided capture data on individual fish from the lower reach that FWS had either initially captured or subsequently captured. Both CDOW and UDWR conduct annual electrofishing surveys of the river during April and May as part of the Interagency Standardized Monitoring Program (ISMP). Capture data from the lowermost 3.5 km of the Gunnison River were supplemented with those from a concurrent FWS electrofishing survey of that river (see Burdick 1995). Though no systematic, river-wide searches for marked fish were made during 1995, we utilized recapture data available from other surveys. This data was from four sources: lower Gunnison River surveys, a FWS survey of ponds near RK 263 in the Walter Walker Wildlife Area (see Mourning 1995), and the aforementioned ISMP surveys by CDOW and UDWR. Body Condition Relative body condition (Kn) was calculated for each fish for which we had lengths and reliable weights (those measured with an electronic balance). As noted by Hawkins (1992), relative condition (Kn) is a better statistic than is the more widely used Fulton's condition factor (K) because relative condition is comparable between fish of different lengths; Fulton's condition factor does not account for allometric growth and therefore varies by fish length making comparisons among sizes inappropriate (see Le Cren 1951). Relative condition is the observed mass of a given fish divided by the expected mass for a fish of its length: Kn = M * 100 A The expected mass (Me) is calculated using constants derived from mass-length regressions: Log„Me = ((Log,, length) slope) + y-intercept Because Hawkins (1992) showed that Colorado squawfish condition changes monthly, we first developed mass-length relationships specific to the month during which the fish were captured. Though Hawkins provided weight-length regression coefficients for Colorado squawfish captured from the Colorado River during 1978-1989, we used our own data to derive new coefficients because 1) our monthly sample sizes were larger, 2) we used juvenile as well as adult sized fish (z 181 mm TL as opposed to _> 428 mm TL used by Hawkins), and 3) our weights were presumably more accurate (because of the use of a balance as opposed to spring scales that were widely used in the past). We calculated mass-length relationships separately for the months of April, May and June using 1990-1994 capture data. Only fishes weighed with an electronic balance were included. Excluded from the June calculations were 1994 data because early gonadal maturation that B-5