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18 squawfish in the Colorado River in the Grand Valley (average 1.4/year) than in the lower Colorado River (average 3.2/year) or the upper Green River (average 6.3/year); areas represented by the creel survey. Therefore, the IRO estimate of 12 adult squawfish per mile is probably conservative for the survey areas. Using this figure, an estimate can be made of 540 adults on the 72 km of the Green and 624 on the 84 km of the Colorado within the survey sections. Despite the fact that all Colorado squawfish were reportedly released, hooking mortality is probably the fate of some of those captured. More than 90% of the anglers were fishing with bait, and bait fishing produces the most mortalities. Behnke (1991) reported an average, gleaned from several other studies, of 40% mortality on salmonids caught with bait, compared to 5% for artificial lures. Other studies on walleye (Stizostedion vitreum) caught with bait report lower mortality rates than for the salmonids (2 to 23%) (Payer et al. 1989; Schaefer 1989). No hooking mortality studies have, been conducted on Colorado squawfish, but we will assume 25% hooking mortality for the squawfish in this study caught on bait. Since all squawfish caught in the Green River were caught with artificial lures, hooking mortality may be lower. Some previous records of incidental angler catches and mortalities of squawfish are available. In the years from 1980 to 1991, a total of 112, or 10/year, squawfish were reported