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(Templeton, 1990), or inbreeding may arise and further complicate the situation. A second alternative lies in the use of cutoff bays in Lake Mohave as semi-natural breeding sites. This requires removal of predators from isolated backwaters, stocking adults to spawn unattended, and releasing both adults and their progeny back into the lake (Marsh and Langhorst, 1988; Hinckley ~et al., 1991). Repetition of this procedure in several cutoff bays over a number of years (using different adult individuals directly obtained from the lake each year) will result in production of a diverse group of cohorts. Five, one-year pilot bays used a total of 145 females between 1984 and 1992. Progeny of sizes large enough to escape predation were produced and freed into the lake in two of those five years. If 10 such bays were established and 40% successful (as above), approximately 120 different females could contribute progeny each year. Continuation over a number of years would thus maintain far more genetic variability than possible under most hatchery conditions, but again, space availability (i.e., number of hays) limits the number of fish contributing each year. Another disadvantage of this alternative is a lack of control over reproduction, making it impossible to equalize contribution within and among bays or insure that all individuals actually reproduce. A third option is the direct capture and short-term husbandry of wild-spawned larvae from Lake Mohave, followed by their reintroduction into the reservoir. Larval razorback suckers appear along shorelines of Lake Mohave in December-Ianuary and may persist to April-May (rarely into Iune). They are positively phototactic and readily collected, manually or by light traps (Marsh and Langhorst, 1988; Bozek et al., 1991; Mueller et al., in press). Numbers captured vary with absolute number of larvae present, weather and lake conditions, light sources, personnel, etc. Two dedicated collectors can nonetheless harvest hundreds to thousands in a few favorable nights. There is evidence based on tag-recapture data that a large proportion of the individuals in Lake Mohave reproduce each year (Marsh„1994), so 2b