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10 to come only from deeper, off shore habitat toward the middle of the backwater. These observations were consistently repeated, and are evidence that razorback larvae assume a benthic habit in deeper water as they increase in size beyond ca 12 mm. Five larvae, all >15 mm TL, were taken by larval trawl from the deepest portion of the backwater on 18 April. We further attempted to rear suckers in small enclosures to examine larval growth. Cages of wooden frames (15x15x30 cm) covered with 0.25 mm-mesh mosquito netting were suspended at a given depth or anchored to shoreline vegetation. In early March 1985, larvae were collected from Hammerhead Cove and the Arizona Bay Backwater and placed in cages at the former (N = 3 replicates) and latter (N = 2) sites. Initial mean larval TL was 10.4 to 10.6 mm (N = 25 to 50 per replicate). Eighty percent of larvae survived the first 2-3 weeks of restraint and showed modest growth to 11.5 mm. While only a few larvae survived as long as a month, they showed mean increase in length as great as 3.1 mm, nearly 30% of initial sizes. We attribute most mortality in cages to poor experi- mental control: repeated acts of vandalism and/or tampering, escape of agile larvae through small tears or loose areas of the mesh covering, and wave action washing cages onto shore. Despite these problems, it is clear that larvae reared in cages survived long enough to attain total lengths significantly greater than any collected from the lake. On 10 April, 10 relatively large (18 mm TL) sucker larvae were collected in the Arizona Bay backwater and placed in a cage in Hammer- head Cove. Three larvae died within 24 hours, but remaining fish survived more than 3 weeks and attained lengths of up to 34 mm TL, the largest we have seen outside of hatchery situations.