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each system for the target species. The number of specimens collected was based on the rate of encounter. When fish were abundant we would collect sufficient numbers for our study. However if specimens were rare we would reduce the number of specimens taken because of the potential of negatively impacting individual populations. As stated in the proposal, we hoped to obtain a minimum of twelve individuals of each of the species from each of four sites in each major river system. Field Work , Sample collection and handling: The collections were made with either a Smith-Root backpack shocker or seines. When state or tribal fisheries biologists accompanied us on the collections we utilized their electrofishing equipment. Prior to all trips we notified the appropriate regional biologists/managers, often also obtaining advice on the best locations for collecting the specimens needed as well as receiving information on the location of populations from which the state did not want specimens removed. A standard protocol was followed for preserving specimens (both fin tissue and whole specimens were collected in the study). Alcohol preserved samples - whole fish and fin clips for DNA analysis. 1. We used gallon containers and alcohol for preserving whole specimens. Small 2.4 ml polypropylene vials were used to hold the fin clips. The whole fish were fixed in 70% ETOH. Fin clips were placed in 95% ETOH. 2. Whole fish were between 3.5 and about 30 cm in length. A range of 15-25 cm is ideal but we kept larger fish at one site and fixed them in a 10% buffered formalin solution. Small fish (2.5-8 cm) will yield adequate DNA. Fin clips were approximately 1 to 2 cm on a side, roughly 1/2" square. 3. We attempted to collect between 15 and 30 fish per population. If the population numbers seemed very low, we collected fewer than our goal, as we are able to obtain data from a sample size of 10-12. As a general rule, if many fish cannot be collected from a population and mainly fin clips are taken, it is still useful to have some whole specimen vouchers archived in the museum for future study. For this, about 12 fish per population is adequate. 4. When alcohol preservation of whole fish specimens was used, we killed the fish with an overdose of MS222. Fish that were to be released were anesthetized prior to having the fm clipped. 5. We have found considerable variability in the quality of DNA from alcohol preserved fish, while fin clips have given excellent DNA yields. This is probably because we often use internal tissues (muscle) for DNA extraction from whole specimens (to minimize damage to the fins of the voucher specimens), and if the fish is not fixed rapidly, significant DNA degradation 2