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8 Hammerhead Cove into April, although few adult suckers were in that area and no spawning occurred there after late January. Larvae were captured in shallow (<3 m) littoral zones of Hammerhead Cove. Substrate varied from cobble-gravel to fine sand, often strewn with organic debris derived -largely from riparian saltcedar (Tamarisk). Larvae often were associated with partially submerged shoreline vege- tation, although they were not restricted to such habitat. Occasional larvae were taken in deeper (5-7 m) water away from the shoreline, but not beyond the mouth of the cove. Larvae in Arizona Bay were collected near shore in 0.5-3 m of water overlying adult sucker spawning habitat. A conical larval trawl (1 m mouth diameter, 3 m length, 1.0 mm Nitex was deployed along shorelines and in open lake areas adjacent to Hammer- head Cove and Arizona Bay (Fig. 4) between 18 February and 18 April, a period when larval suckers were readily taken from shoreline areas by light at night. The net was towed for 15 minute periods during all times of day and night at ca. 5 km/h and depths of 2 to 15 m. A single larva (13 mm TL) was taken (8 April 1985, 0745 hrs, Arizona Bay area) despite a total effort of 22.0 net-hours. Because larvae were known to be agile at avoiding capture, at least by dip net, we suspected the trawl was ineffective. However, its capability to capture larvae was convincingly confirmed for razorback larvae by experimental tows which caught ca. 5 larvae/min in the Arizona Bay backwater. We conclude that . razorback larvae were either unavailable or so few in number as to not be collected in sampled areas, and assume that if larvae are abundant anywhere in the lake exclusive of nearshore habitats, they must be at depths greater than 15 m or near bottom. Observations of larger larvae in the Arizona Bay backwater provide evidence in support of this last