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in a squawfish stocking program are areas of.research of high priority. First, the magnitude of the predation problem must be determined. Predation probably varies greatly between backwater sites due to the difference in the number of predaceous fish present, the availability of buffer prey species, presence of cover or means of escape, and addi- tional mortality-factors. Stein et al. (1981) found that bass predation accounted for 26% of the mortality of tiger muskellunge (Esox masquin- o_ngy x E. lucius) after stocking at one lake and 45% at another. Time of stocking, environmental stresses and disease were other mortality factors. There is little information on improving survival of stocked fish by stocking them in semi-controlled riverside ponds. Unsuccessful attempts have been made to condition stocked fish in pens (Johnson 1973). Pacific salmon are often reared in flood control reservoirs rather than hatcher- ies or streams and emmigration is induced by drawdown (Korn and Smith 1971). Isolation coves have been suggested as a means of increasing the survival of stocked tiger muskellunge (E. masquinongy), and have been employed to monitor post stocking mortality (Belusz 1978). The semi-con- trolled pond could be considered a type of extensive culture that has been historically practiced when rearing coolwater species (Webster et al. 1978), and which-is now becoming important in commercially rearing cool- water species (Nickum 1978). Abundance, vulnerability, palatability, behavior.and size of prey organisms affect the feeding behavior of largemouth bass. Stomach con- tents of wild largemouth bass can reveal the types of fo-od'comronly eaten but the cause of selection for particular items is generally unknown. Whether an item is eaten because it is more abundant, more easily caught, or simply-is more preferred has remained a question. It is an important question because the most desirable and easily obtained foods are likely to be eliminated first (Lewis et al. 1961). Lewis et al. (1961) found that largemouth bass in small tanks fed more heavily upon golden shiners (Notemigonus,crysoleucas) than on tadpoles (Rana catesbeiana and R. pipizns) and crayfish (Orconectes immunis); in small ponds, however, they utilized more tadpoles and crayfish than fish (Lewis and Helms 1964). The change in utilization in the two envir- onments was thought to be due to the differences in vulnerablity of the forage organisms. Under tank conditions (confinement-no escape cover), 27