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Areas used for spawning can be far away from areas inhabited during the r rest of the year. Northern pike tagged on spawning grounds in a Missouri River reservoir were later recaptured up to 322 km away; most, however, were caught within 32 km of the site where they were tagged (Moen and Henegar 1971). Pike tagged during the upstream spawning run out of a Michigan lake were subsequently recaptured up to 15 km away in the lake (Carbine and Applegate 1948). The degree to which northern pike home to particular spawning grounds is unclear. Tagging and meristic studies of northern pike in Lac La Ronge, Saskatchewan, suggested the presence of separate populations within the lake, but. it is not necessary to postulate a homing instinct to account for this observation (Koshinsky 1979). The northern pike did not disperse far from the mouths of tributaries used for spawning. In spring, they may simply have moved up the nearest suitable stream (Koshinsky 1979). Frost and Kipling (1967) also gave evidence of repeated use of a spawning area in a lake in England, but their results did not conclusively demonstrate homing. Miller (1948) reported movements of several northern pike among widely separated (2.4 to 3.2 km) spawning areas within a 10-day period. He did not note whether the fish were ripe at each capture location. Franklin and Smith (1963) concluded that northern pike in a Minnesota lake do not home to particular spawning grounds. Specific Habitat Requirements Northern pike are not adapted for life in strong currents. Throughout their ,range, they occur more frequently in lakes than in rivers (Grossman 1978), where they inhabit backwaters and pools (Christenson and Smith 1965; Kamyshnaya and Tsepkin 1973; Paragamian 1976; Kallemeyn and Novotny 1977). They avoid channelized reaches (Kallemeyn and Novotny 1977). Strong currents (> 1.5 m/s) can block spawning migrations (Dryden and Jessop 1974). The availability of suitable spawning habitat is the factor which most often excludes northern pike from lakes, reservoirs, and slow moving rivers and which limits abundance where the species does occur. Shallow vegetated areas, such as flooded marshes, flooded terrestrial vegetation, or weedy bays provide suitable habitat, provided that high water levels are maintained throughout the embryo and fry stages (Hasler 1970). Strong year-classes often occur as a newly created reservoir fills and in years when exceptionally high spring water levels flood previously unflooded terrestrial vegetation (Crabtree 1969; Cooper 1971; June 1976; Groen and Schroeder 1978; Nelson 1978). Conversely, weak year-classes in impoundments and natural environments are associated with low water levels (Johnson 1957; Cooper 1971; Schryer et al. 1971; Rundberg 1977; Nelson 1978; Stewart 1978}. Northern pike do not do well in reservoirs with widely fluctuating water levels (wajdowicz_ 1964) because nearshore vegetation does not develop. Long term reductions in the abundance of northern pike have accompanied the draining and filling of wet- lands (Brynildson 1958; Threinen 1969; Baumann et al. 1974; Forney 1977), reductions in the density of aquatic plants (Hurley arrd Christie 1977; Ciepielewski 1981), and blocking of access to spawning grounds (Trautman 1957). Fishery managers in Michigan were able to substantially increase 4