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with peak hatching at 120 hours. Following swimup, fry are stocked in ponds at the same rate as razorback sucker. Ham man (in press) reported Colorado squawfish spawning for 1983 and 1984. In 1984 nine domestic Colorado squawfish females averaging 3.2 pounds produced a total of 595,672 eggs. Mean egg take was 66,185 and number of eggs per pound of body weight was 20,656. In 1985 they averaged 3.6 pounds and 18 females produced 1,490,006 eggs fora mean egg take of 82,778 and 22,921 eggs per pound of body weight. In 1984 107,951 swimup fry were stocked and 102,774 1.5" fingerlings harvested fora 95% return. These fish were restocked to produce larger fingerlings and 8b,060 (83.7%) were harvested in the fall. They were held over the winter in an attempt to stock larger fish in 1985. Due to cannibalism, predation by birds (particularly gulls), and perhaps other unknown factors (pond conditions were good), only 220 fish (.0025%) survived the winter. On July 24, 1985, the final rule determining "experimental population" status for certain reintroduced populations of Colorado squawfish and woundfin was published in the Federal Register. On August 26, under this new designation, 196 four- year-old Colorado squawfish were released into the Verde River near Perkinsville, AZ. An additional 30,000 2" fingerlings were stocked in Cherry Creek (tributary of the Salt River, AZ) on August 28. A total of 116,789 1.5-4.5" fingerlings and 301 14-16" subadults were released in Arizona waters in 1985. We are maintaining 200 twelve-year-old broodfish and 300 five-year-old future brood. Bonytail Of all .the unique native Colorado River fishes, bonytail has come the closest to extinction. Apparently only a few old fish remain in the lower basin (W. L. Minckley, "pers. comm.), and only an occasional collection has been made in the Gray Canyon area of the Green River in the upper basin (Tyus et al. 1982). Extensive collecting efforts during the past 11 years to obtain bonytail for culture purposes produced only 24 fish and all are now dead. Bonytail also are long-lived. Recent age determinations made from otoliths of two Lake Mohave specimens by Bruce Taubert (pers. comm.),, Arizona Game .and Fish Department (AGED), placed their age at 40 and~42 years. Ham man (1982) successfully spawned bonytail at Willow Beach NFH in 1981. Some of the resulting fry were reared at Dexter NFH and now constitute a captive held broodstock. Spawning trials on two and three-year-old domestic bonytail broodfish were carried out in .1983 and 1984 (Hamman 1985b). During April and May 1983, 24 -39-