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minimum habitat size). This distance will vary, depending on climate, locale, density of eggs, and other factors. Depth. The relationship of water depth to suitability of striped bass habitat is unclear (Crance 1985). A minimum depth of 0.46 m (1.5 ft) is assumed to be needed for adults to swim upstream to spawning areas. Areas with depths of 1.8 to 2.1 m (6.0 to 7.0 ft) may be needed to provide temporary refuge from boat traffic and excessive current and sunlight. Spawning has been reported to occur in waters less than 1.8 m (6 ft) deep and at depths up to 15.2 m (50 ft). A depth range of about 1.8 to 9.1 m (6 to 30 ft) is assumed to be optimal for spawning. Extreme depths are not conducive to turbulence, which is usually associated with spawning areas. Loss of deep-water habitat may have been one of the reasons for the decline of striped bass in Chesapeake Bay (Price et al. 1985). If dissolved oxygen and water temperature levels are within suitable ranges, depths selected by striped bass in lacustrine habitats are determined to a large degree by food availability. Stratified lakes with a mean minimum depth less than about 6.1 m (20.0 ft) and unstratified lakes with a mean minimum depth less than about 1.8 m (6 ft) are likely to be unsuitable lacus- trine habitat for juveniles and adults during summer. Juveniles are commonly caught in seinable waters 0.6 to 1.8 m (2 to 6 ft) deep (Crance 1985). Substrate. The relationship of substrate to suitability of striped bass habitat is unclear (Crance 1985). Substrate is probably not a limiting factor except where eggs or larvae settle to the bottom. Substrate composed of particles large and/or dense enough that excessive amounts do not become I suspended often is generally considered most suitable for spawning and egg incubation. However, spawning occurs over mud/silt in some coastal streams in Georgia and in Chesapeake Bay and over peat and sand substrate in California waters (Crance 1985). Data presented by Van Den Avyle and Higginbotham (1979) indicated that juveniles in a Tennessee lacustrine habitat preferred sand substrate during October and November but showed no preference for substrate type during other months. Shoreline seining for juveniles in Oklahoma reservoirs was most productive over sandy substrate (Mensinger 1971; Harper 1982). Cover. The relationships between cover and suitability of striped bass habitat is unclear (Crance 1985). Adults and larvae likely use instream cover for resting and protection. Streambank cover (trees or vegetation) provide shade, which may. help to reduce excessive light penetration and buffer the water temperature. Larvae and juveniles in lacustrine habitat are commonly found over sandy substrate in shallow water. They may use cover, such as submersed vegetation, for foraging and protection from predators. Harper (1982) reported that juveniles were found least frequently in vegetated coves. Adults are sometimes abundant in lacustrine habitat near submersed islands or shoals, large boulders, brush, overhanging ledges, and/or old river channels. 10