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4 <br />would also provide information on post-stocking dispersal. A small number <br />(about 10 to 20 per target stocking site) of adult fish of hatchery-origin <br />would be stocked in early spring and equipped with radio transmitters. After <br />release they would be monitored weekly prior to and during the spawning <br />period; monthly for the remainder of the year. Areas where radio-equipped <br />fish are located during the suspected spawning period would be sampled with <br />entanglement nets. Captured razorback suckers would be checked to note <br />spawning condition. If gametes are expressed this would indicate that water <br />temperatures are probably adequate for spawning. Furthermore, this may allow <br />investigators to delineate the type of habitat utilized by razorback sucker <br />for spawning, and monitor the behavior of these fish following spawning. <br />Radio-equipped adults would be monitored after the suspected spawning period <br />to delineate post-spawning movements and specific habitat-use patterns. In <br />reaches where upstream barriers exist, the attempted movement of <br />radio-equipped razorback suckers past these barriers would provide evidence <br />for the need to either provide passage around or over such barriers, or if <br />feasible, modify or remove such barriers. <br />To determine what effect implantation of radio transmitters might have on <br />adult razorback sucker reared in a hatchery and grow-out ponds, a small number <br />of adult razorback sucker could be radiotagged and held in captivity. <br />However, past studies (Tyus et al. 1987; Valdez and Masslich 1989; Osmundson <br />and Kaeding 1989a) have shown no ill effects of radio transmitters on wild <br />razorback sucker. <br />If the initial experimental stocking of razorback sucker is successful <br />and subsequent stocking of fish is warranted surveys would be performed <br />annually for stocked fish in late spring during runoff. Tyus et al. (1987) <br />34 <br /> <br />4 <br />4