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I I I I I I I I I I I I I I I I I I I Reach I: Dolores-Colorado River Confluence (RM 0.0) to Utah-Colorado Stateline (RM 22.7) (Corresponds to Service's Stratum T) Reach II: Utah-Colorado Stateline (RM 22.7) to Salt Creek (RM 41.3) (Corresponds to Service's Stratum U) Reach ill: Salt Creek (RM 41.3) to Dolores-San Miguel River Confluence (RM 64.4) (Corresponds to Service's Stratum V) Reach IV: Dolores-San Miguel River Confluence (RM 64.4) to Paradox Valley at Bedrock (RM 74.8) (Corresponds to Service's Stratum W) Reach V: Paradox Valley at Bedrock (RM 74,8) to Dolores-Disappointment Creek Confluence (RM 128.7) (No corresponding Service's Stratum) Reach VI: Dolores-Disappointment Creek Confluence (RM 128.7) to Bradfield Bridge (RM 177) (No corresponding Service's Stratum) 3.0 METHODS 3.1 Sample Collection Sample collection was conducted during six periods over the course of this study (Table 1). Each period consisted of approximately 10 days afield, Field trips were scheduled so that sampling could be conducted on a seasonal basis, including spring pre-runoff (March/April), summer post-runoff (July/August), and fall (September/October). 3.2 Sample Effort and Techniques Total sample effort for this project consisted of 107 jon boat electrofishing runs (total current- on-time of 36.4 hours), 150 canoe electro fishing runs (current-on-time of 58.9 hours), 44 experimental gill net sets (142.7 hours), 5 gill net sets (9,1 hours), 37 trammel net sets (63.1 hours), 3 floating trammel net sets (8.2 hours ),and 284 seine hauls (Table 2). An attempt was made to expend similar sample effort during each of the trips. However, actual sampling effort varied because of increasing familiarity with the study area, refmement of logistics and variable sampling conditions associated with each trip. Time used to conduct reconnaissance and general habitat surveys also decreased through the study, which allowed for additional sampling time. Standard gear and techniques were used to sample fish in the Dolores River. The three principal sampling techniques were seining, electro fishing and netting with gill and trammel nets. Various gear types proved more effective in certain areas because of the wide range of flows and channel characteristics encountered. Seining was used to collect fish in all shallow habitats, Seining was most effective for sampling the early life stages of the larger fish as well as a range of the smaller species. Information documented with each seining effort included: sample size (length and width), maximum depth of sample, primary and secondary substrates, primary and secondary habitats, 3