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9 assumption (see below). It is inconceivable that densities would be so low as to result in catch of only 0.045 larvae per net-hour when hundreds could readily be taken by dip net near shore. We thus generated no new quantitative information on dispersal of larvae from areas of known abundance, nor of_ t.heir presence elsewhere in Lake Mohave proper. Larvae disappeared from the Hammerhead Cove area, and presumably from surface waters of the entire lake, by mid-April. Sucker larvae captured in Lake Mohave averaged 10.6 mm total length (TL) from early February through early April (Fig. 5), indicating continuous spawning and cohort production during the period. Because neither mean nor maximum length increased, there was no evidence of larval growth; the largest captured was 12.2 mm. Since swimup is achieved near 8.5 mm (Marsh 1985) and larval growth rates are known to be rapid at obtaining temperatures (Papoulias 1985), we estimate maximum age of the largest specimens at only a few weeks. A contrasting situation occurred in the Arizona Bay backwater. Larvae were first captured on 7 March, approximately 2 months after adults were stocked. Larval numbers increased quickly, and remained high into April (see below). Mean total length of backwater larvae was initially similar to that of fish from Lake Mohave (Fig. 5), but the former attained lengths greater than 16 mm by 28 April, when the largest specimen was 20.3 mm TL, similar to sizes attained by hatchery fish in a . comparable period (Hamman 1985, Papoulias 1985). Habitat use changed as sucker larvae increased in size. Small (<12 mm) larvae occupied shallow margins of the backwater. A bright light directed toward water ca 20-50 cm deep attracted these larvae from all directions but most were from near shore. In contrast, larger (> 15 mm) larvae so attracted appeared