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the surface) with a Marsh-McBirney current meter. Microhabitat use by adult Colorado squawfish was also evaluated by collecting depth, velocity, and substrate data 1 to 2 m inshore (shallow) and offshore (deeper) from the signal source in 1984 and 1985. Substrate type was obtained by direct observation and by probing with a wading rod. For additional information on radiotelemetry methods see Tyus {1987). LARVAL COLORADO SQUAWFISH COLLECTIONS Systematic basin-wide collections of larval Colorado squawfish were initiated in the Green, Yampa, and White rivers in 1981 to aid in locating potential spawning areas. Qualitative (presence/absence) and quantitative (catch per effort) sampling programs were continued through 1985 in Green River to confirm existence of suspected spawning sites and to establish spawning dates. Qualitative samples were also taken at weekly intervals during July and August, 1983 to 1985, in "best" backwater habitat encountered at the two confirmed Colorado squawfish spawning areas (Yampa Canyon, Yampa Aiver and Gray Canyon, Green River) in order to obtain presence/absence and growth data for Colorado squawfish. Catch per effort data were collected from shallow backwaters (water depth < 12 in), deep backwaters (water depth > 12 in), and shorelines using a systematic sampling program in 1981, 1964, and 1985: 1. At the top of each stratum, a team proceeded downstream 8 km (5 mi) and initiated sampling. One shallow and one deep backwater were2 sampled twice (two replicates) with a larval seine (about 0.8 mm mesh) in the first 0.8 km (0.5 mi) reach. If all habitat types were not available in the initial 0.8 km (0.5 mi) reach, those missing were sampled in the remaining 7.2 km (4.5 mi) of the section. Records of depth, velocity, and substrate, as well as sampling effort, were taken for each sample site. Sampling sites within 15