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centered in a large cove over a gradual slope with similar substrate typical of Lake Powell shoreline. Groups of fish spawned on or near the surface from 2300 h until dawn. Dead striped bass eggs were collected in the area the next day. Live eggs were not found and thought to have settled on the substrate (Gustaveson et al. 1984). In subsequent years, as average size of fish declined collection of mature fish ceased. Many previously mature females suffering the effects of malnutrition had senescent ovaries incapable of emitting viable eggs. From 1985 to 1995 no 4-8 pound females with viable eggs (Bonn et al. 1976) were found. Striped bass females exceeding 10 pounds, though few in number, were healthy and responsible for producing each succeeding annual year class of striped bass. Young ripe males were found every year sometimes in greater abundance than others. Small females less than 4 pounds never developed viable eggs, regardless of age, in the forage-poor era that marked the late 1980's. The prespawning aggregation of striped bass near the dam persisted despite the lack of sexually mature fish. Spring prespawn staging striped bass have been absent only 3 years out of the last 17. Those absences occurred following threadfin shad population peaks when forage was readily available in uplake locations. Apparently attraction to current in the spring time is an overriding stimulus triggering striped bass migration even when fish are not sexually viable. The only environmental stimulus stronger for most of the population is food availability. When food is available in a specific location, striped bass will spawn in place without extensive migration. Spawning movements have evolved with subsequent generations of striped bass. The first striped bass were stocked in Wahweap Bay (1974-78). with maturity they returned to Wahweap to spawn as described previously. Subsequent generations seemed to exhibit a more nomadic tendency and have spawned in the backs of many canyons where small flowing streams entered. Spawning now is 29