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An effort should be made to track the abundance of the founding population. Thus far, translocated fish have only been batch marked with fluorescent elastomer tags, and there appears to be some tag loss (21 %; Stone and Sponholtz 2003). This precludes mark-recapture efforts to track the population. Once fish reach 150 mm, they can be PIT tagged; allowing mark-recapture studies to precede, however, a funded program to do so must be established, and we recommend that Chute Falls monitoring be a part of the routine monitoring in the LCR. Generally, managers respond to a potential threat of decreasing a wild Ne by artificially imposing gene flow into the smaller population (i.e., the One Migrant Per Generation rule [OMPG]; Mills and Allendorf 1996). For example, 1 to 10 fish might be moved each generation above Chute Falls. Although such remedial tactics appear to prevent fixation or further loss of heterozygosity within the small population (Mills and Allendorf 1996), it does not appear to address the initial problem (i.e., a very small founder population will likely have decreased initial heterozygosity). Additionally, the OMPG assumes no natural selection is occurring in either population (i.e., only drift and gene flow are in operation). Swamping the translocated fish with a high number of fish from the main LCR population each generation may be an alternative to using the OMPG. Managers could repeat the movement of fish above Chute Falls for several years and then continue to move smaller numbers of fish (say 100 age-1 fish) once a fish generation. This approach is suggested by P. Hedrick (ASU, pers. com.), who believes that the OMPG is inappropriate in this instance and that the numbers should be higher. Some effort should be made to monitor for potential inbreeding (loss of heterozygosity in either the translocated population or the main LCR population). Since the processes of inbreeding takes generations, it should be possible to monitor for these changes, should they occur. However, tissues must be taken to genetically analyze the fish and a funding mechanism identified to analyze samples. It will be difficult (if not impossible) to accurately measure downstream levels of movement from the resulting offspring above Chute Falls. Attempts could be made to monitor downstream drift of larvae with drift nets, batch mark age-O fish, or PIT tag fish once they reach 150 mm, but these efforts will likely contain a high degree of uncertainty. For example, most offspring should be expected to move downstream (below Chute Falls) at small sizes (before they can be batch marked or tagged) during flood events, which is also when drift nets become problematic (e.g., currents become too strong and nets very quickly fill up with debris; D. Van Haverbeke, pers. obs.). However, if genetic samples are obtained, it may be possible to detect changes in the populations. Summary In summary, uncertainties exist about potential genetic impacts to the main population of humpback chub below the falls (e.g., concerns with inbreeding, effective population 41