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6. MANAGEMENT RECOMMENDATIONS " It is difficult to overestimate the importance of CHLP in the conservation and potential recovery of the bonytail and razorback sucker. The discovery that these fish can complete their life cycle in isolated ponds provides the first glimmer of hope that these species can be effectively managed. The self-sustaining nature of the community provides an opportunity to examine complex ecological issues on a scale that is realistic, economical, measurable and most importantly manageable. Currently, this opportunity does not exist anywhere else in the basin. Efforts to establish additional native communities have thus far proved unsuccessful (Brouder and Jann 2004). While the success of natural recruitment at CHLP is often described as something that we need to duplicate, there has not been any attempt to actually duplicate the physical conditions found at CHLP. How To Build a Native Fish Refugia-The factors that have contributed to the success of CHLP are undoubtedly many, but there are obvious ones that should be considered in the construction of new habitats. These include: 1.. Absence of Predatory Fish The initial renovation of CHLP appears to have been successful. Stocked fish not only survived but were able to mature and produce young in a relatively predator-free environment. Remarkably, it took 5 years (1993-1998) before bonytail and razorback sucker young were noticed. Recolonization by unwanted fishes is inevitable. Small numbers (<20) of shad, bluegill, largemouth bass, and channel catfish have been removed during the past decade, however, their numbers have remained quite low and only adults were found. We believe the majority--if not all of these fish--were introduced by anglers. Overall predation has not been eliminated; it has simply been reduced to a level that allows natural recruitment at a level where the community is able to sustain their number. Native fish eggs, larvae and fry are taken by crayfish, predatory insects, tadpoles, bullfrogs, and birds; even larger (>40 cm) natives fall victim to herons and osprey. It is quite possible non-fish predators could suppress natural recruitment and even the stocking of small fish if adequate cover (e.g., water depth, turbidity, structure) was not available. Regardless of structural safeguards and monitoring, predation will remain a daunting challenge. It is not a matter of if, but when, predators invade these habitats and that influences if and for how long natural recruitment will occur. Therefore it is critical that mature fish be included in the initial stocking to allow spawning to occur as soon as possible. For instance, bonytail become sexually mature in the first or second year, but it takes razorback females 3-4 years to become sexually active. If only juvenile suckers are stocked, it provides non-natives ample time to recolonize and expand their populations to thwart any change of native recruitment. This is not an issue if ponds are only being used to rear or hold relatively large individuals. 18