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Given the above cautions, there is a term called "conservation aquaculture" or "conservation reintroduction" (Anders 1998, Brown and Day 2002). Conservation aquaculture is the use of aquaculture for conservation and recovery of endangered fish populations. Its goal is to conserve wild fish populations and their locally adapted gene pools, including the characteristic phenotypes and behaviors (Anders 1998). In theory, it differs from standard hatchery production practices that traditionally focus on production of large numbers of fish. Conservation aquaculture is considered justified by some when fish populations in the wild become too small (i.e., when Ne in the wild becomes too small; Anders 1998). However, this potential for gain is accompanied by genetic and behavioral risks to the wild population. Ideally, conservation aquaculture should be performed before populations in the wild reach critically low levels (i.e., low Ne). The practice should be complimentary (rather than in lieu of) other conservation measures designed to improve seriously degraded habitat (Anders 1998). Furthermore, if hatchery programs ignore the risks associated with aquaculture (inbreeding depression, domestication selection, disease, etc.), failure is certain (Brannon 1993, Anders 1998). Conservation aquaculture should (in theory and in practice) reduce common risks associated with standard hatchery procedures, such as competitive feeding behaviors, reduced growth rates, domestication selection, and increased incidence to disease (Anders 1998). Brown and Day (2002) discuss some specific techniques that can be used to overcome some of these problems, including environmental enrichment, life skills training, and soft release protocols. Basically, these techniques are used to overcome ethological (behavioral) problems rather than genetic problems. Fish that are held in captivity for a substantial portion of their lives are removed from natural learning experience that would ordinarily be gained in the wild. Consequently, their behavior can be altered in ways that severely impact survivorship and ability to reproduce upon release into the wild (Brown and Day 2002). The most important effects appear to be lack of development of anti-predator responses (Vincent 1960, Olla et al. 1998, Brown and Day 2002), lack of ability to feed efficiently (Ersbak and Haase 1983, Brown and Day 2002), and reduced reproductive performance (Jonsson et al. 1990, Fleming et al. 1997). For instance, early life experience for migrating salmon has been shown to be important for ascending their natal river to spawn (Hasler and Scholz 1983, Hansen and Jonsson 1994, Jonsson et al. 1994), and for locating breeding sites (Jonsson et al. 1990). These types of effects might be particularly relevant to humpback chub in Grand Canyon, since a large portion of the population migrates (Valdez and RyeI1995). To offset some of these concerns, conservationists are calling for an interface between ecology and behavior, particularly in reintroduction biology (Olney et al. 1994, Clemmens and Buchholz 1997, Caro 1999a,b, Gosling and Sutherland 2000). Olla et al. (1994, 1998) suggested it is critical for hatcheries to implement methodologies that improve post-release survival. Brown and Day (2002) suggest that environmental enrichment, pre-release training programs, and soft release protocols can assist in making fish more ecologically viable once release occurs. Environmental enrichment 15