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Razorback suckers thrive in ponds or raceways. Nutritious hatchery feeds have been developed and when practical, ponds are enriched to encourage zooplankton. Feeds are administered by hand or from trickle feeders. Hatcheries are able to produce large numbers of razorback suckers cheaply, but the poor survival of hatchery-introduced suckers raises questions regarding their ability to compete and survive. Pond reared suckers are unaccustomed to swimming in currents or foraging for natural foods. I question whether hatchery produced razorback suckers possess the necessary survival skills and stamina to survive. It must be remembered that native fish are being stocked upon existing nonnative fish communities that are at carrying capacity. Recreational stocking on the other hand, is normally conducted to bolster depleted stocks. Site Acclimation and Physical Conditioning Tests Stocking dispersal (30 day) was examined during the past 5 years using eight test groups (15 fish each) of razorback sucker and telemetric equipment. Fish were released in three different habitats: (1) Lake Powell, (2) a small seasonal backwater on the Green River, and (3) Laughlin Lagoon (>30 ha) on the Colorado River. Subgroups were released after being: (1) thermally acclimated to local water conditions, (2) site acclimated 3 to 7 days prior to release, and (3) physically conditioned to flow. Post-stocking dispersal was rapid and declined with time for all tests. Most movement was detected within 2 weeks of release. Dispersal in the Green River was pronounced (x = 69.5 lan/month) and significantly (Kruskal- Wallis, P<O.O 1) greater than either the Lake Powell (x = 3.73 lan/month) or Laughlin Lagoon (x = 7.72 lan/month) groups. Fish sought and resided in slack water habitats that provided adequate cover. Site- acclimation tests were inconclusive but downstream dispersal was significantly (Wilcoxon P<0.05) less for flow-conditioned fish (x = 1.89lan/month) compared to pond-reared fish (x = 7.73 k/month). I believe that pronounced downstream drift is a symptom of chronic stress that degrades performance and the chances for survival. Data suggest razorback sucker dispersal can be significantly reduced if fish are preconditioned to flow and stocked in moderately large (>30 ha) backwater habitats. Literature suggests physical conditioning may have other attributes, including: increased growth, better stamina, and more mucus production. Better swimming skills and increased stamina may reduce predation. While our site acclimation tests were inconclusive, a recent study on the Green River suggests longer periods of acclimation may improve survival. Modde (FWS, oral communication) recently reported that razorback suckers held in backwaters for one year had nearly three times the return rate, compared to suckers released directly into the river. Based on these studies, we recommend that razorback suckers be preconditioned to flow prior to release. Downstream dispersal may not be a concern in reservoir releases; however, physical conditioning also improves growth and swimming stamina that may increase their ability to escape predators. Fish should be stocked in large backwater complexes and jf possible held for several weeks, if not months before being released. A more detailed description of this test can be found in: Mueller, G.A., Marsh, P.C., Foster, D., and Burke, T., 2003, Factors influencing post-stocking dispersal of razorback sucker: North American Journal of Fisheries Management, vol. 23, p. 270-275. 21