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lower Virgin River. These authors also made an important observation that showed that dietary overlaps between woundfm and nonnative red shiners (Cyprinella lutrensis) changed directly with abundance of food. Dietary overlaps were greatest when food was abundant and less evident during periods of low food availability. Some information on the reproductive biology of woundfm is presented by Peters (1970), Greger and Deacon (1982), and from recent reseazch conducted at Dexter NFHTC. The reproductive cycle of the woundfm appears to be initiated by some combination of increasing water temperatures, lengthening daylight, and declining spring runoff. It would appear advantageous for woundfm to spawn as the high spring runoff is declining because eggs spawned prior to this would likely be carried away by the current or buried in silt. Limited spawning may occur in sheltered areas during high spring flows. Gonad maturation has been documented in March, April, and May (Peters 1970), and larvae have appeared in May, June, July, and August (Cross 1975, Deacon 1977a, Hickman 1987b, Hazdy et al. 1989). Spawning occurs during April to July depending on the timing of the snowmelt runoff; late summer spawning in August has also been observed (Hickman 1987a, Hardy et al. 1989). This second spawn may consist of late maturing adults and be precipitated by increased flows associated with Late summer thunderstorm events (Virgin River Fishes Data Base). Deacon and Hardy (1984) and Hardy et al. (1989) found that spawning success increased as the magnitude of flows during the spawning period increased from 2.83 to 22.66 cubic meters per second (m3/s) [100 to 800 cubic feet per second (cfs)]. Observations by Deacon (1977a) indicate woundfin in downstream reaches of the Virgin River begin spawning more than- one month earlier than fish in the upper reaches near La Verkin Creek. This variation of spawning time is probably related to warmer water temperatures downstream. In 1977, the fast appearance of young woundfm in the lower river occurred in early June and in the upper river in late July. Deacon (1977a) reported apparent spawning activities on April 17, 1977, in the Virgin River south of Mesquite, Nevada, when the water temperature was 14.5°C (59°F). Greger and Deacon (1982) observed spawning behavior in an artificial stream at water temperatures ranging from 20 to 25°C (68 to 77°F). These investigators observed spawning behavior similaz to Lockhart and Schumann as reported by Deacon (1977a). A female would leave a pool to join a group of males in swifter flowing water over cobble to gravel-sized substrates. Following spawning, the female returned to the pool. Hickman (1987b) noted that gravid females congregated in deeper water adjacent to riffle habitats during spawning periods. Greger and Deacon (1982) found that spawning in an artificial stream system occurred at velocities from 0.06 to 0.09 m/sec (0.20 to 0.30 ft/s) and at depths ranging from 0.07 to 0.10 m (0.23 to 0.33 ft). The choice of substrates appeared to be fairly specific to cobble or gravel. When larvae appear they are generally found in shallow areas lateral to the main current. Larvae are less abundant in pools containing,predators such as mosquitofish (GamBusia aff~nis), green sunfish (Lepomis cyanellus), largemouth bass (Micropterus 19