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brood stock management plan, and clearly defined methodologies and protocols should be included in the document to prevent or to minimize these risk factors. A suitable hatchery must possess adequate staff, and personnel expertise in genetics and methodologies for the culture of humpback chub. In addition, a suitable hatchery must have committed and long-term funding. To even attempt to do so without adequate funding would be placing the humpback chub in danger. Ideally, a suitable hatchery should be in a closed basin where accidental release of fish and risk of introgression with other Gila spp. will not be a problem. In addition, the hatchery should possess the necessary safe guards to prevent accidental introgression with other Gila spp. being held on station (such as G. elegans). This implies completely isolated space requirements with separate raceways or holding tanks and completely separated plumbing components from other Gila spp. holding facilities on station, as well as no chance for accidental placement of fish. A suitable hatchery should be large enough to hold from 2,500 to 3,000 fish (M. Ulibarri and C. Keeler-Foster, USFWS, DNFH & TC, pers. com.). This should allow for the incorporation and maintenance of sufficient genetic variability. This implies large space requirements that need to be fully explained in a brood stock management plan. Primary physical hatchery qualifications for the culture of humpback chub are water availability and quantity, and the ability to regulate water temperature. Requirements for adequate water supply and water quality are identified in Piper et al. (1989). To induce spawning, water temperatures should be 18 to 19 oC, and optimal temperature for hatching and survival of swim up fry are between 19 to 22 oC (Hamman 1982). Optimal temperatures for growth of humpback chub are between 16 to 22 oC (SWCA 1997); although in temperature growth studies at 12, 18 and 24 oC Gorman and VanHoosen (2000) found the optimal temperature for growth was at 24 oC. It is suggested that methods (reviewed in Brown and Laland 2001, Brown and Day 2002) are followed to help reduce domestication. This implies that flowing water will be needed to raise the fish or at least to condition them prior to release. Finally, any receiving facility would have to be sufficiently large to ensure each individual lot of fish brought in would remain in isolation until health and genetic concerns are fully addressed. For example, all fish brought into a hatchery will need to be quarantined and treated for Asian tapeworm (Bothriocephalus acheilognathl), and any other health issues. This factor by itself could add enormously to the budget. Summary In summary, we suggest the following for establishing captive broodstock(s) of humpback chub in Grand Canyon: 1. Complete genetic studies being performed on humpback chub, and develop a formal brood stock management plan. 22