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This implies supplementing the small original captive populations with wild fish. This also implies using genetic techniques with high resolution, such as micro-satellite' technology, or a combination of mtDNA and micro-satellite technology (Cross 2000). Provided that either the Willow Beach NFH or the 30-mile fish are used to begin an initial broodstock(s), the next step might entail augmenting these broodstocks at a facility yet to be identified to increase genetic variability. In order to build a brood stock of several thousand individuals that equal the genetic constitution of the wild population, more fish would be needed, regardless of what existing or new captive propagation facility is utilized. If the Willow Beach NFH fish are selected as an initial broodstock, we suggest capturing up to several thousand age-O humpback chub from all 14 km of the LCR, over a period of several years. Using age-O fish will avoid depletion of wild adult fish, which are crucial for recovery by means of natural recruitment. The main purpose of temporal spacing would be to maximize the probability of capturing genetic variability, since humpback chub are long lived and not all fish may spawn each year. In addition, it may be advisable to collect fish over a series of months within each year. Gorman and Stone (1999) reported that spawning activity of humpback chub in the LCR commenced in March, peaked in April and waned in May. We know that the LCR hydrograph is variable from year to year, and assume that peak abundance of spawning fish is variable from year to year. Selecting fish in a manner that could disrupt timing of natural migration and spawning patterns should be avoided. For instance, if all age-O fish collected came from a March spawn, this might select for fish that will only spawn in March. Such imposed changes in natural migration and spawning patterns have been documented, and shown to be detrimental for salmonid broodstock (Flagg et al. 1995, Fleming et aI., 1997). Much as the potential problem that could result from not capturing fish on an appropriate temporal protocol, selective changes could occur from not capturing fish in an appropriate spatial manner. For instance, Douglas and Marsh (1996) hypothesized that the altered regime of the mainstem may be forcing humpback chub to adjust its life history, and that fish are being selected to be residents in the LCR. It could be possible that age-O fish collected in the lower reaches of the LCR may be more representative of mainstem migrants, while age-O fish captured in the upper reaches of the LCR may be more representative of humpback chub locally adapted to being residents in the LCR. We suggest a first year attempt to capture an equal number of fish from Boulders, Coyote and Salt reaches (0 - 5 km, 5 - 10 km and 10 - 14.2 km respectively). Capture of age-O fish may be easiest in the Boulders or Coyote reaches, as catch-per-unit-effort of age-O humpback chub has been higher in these reaches in the past (Van Haverbeke and Coggins 2003). We suggest keeping the number of fish captured low (e.g., 300 fish) during any given capture event to accommodate a temporally spaced collection protocol, and to minimize impact on the wild population. Before the first fish is captured, aI/logistics, protocols, methods, etc. must be in place. The broodstock facility must also 19