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N to 00 lool C) c., CHAPTER 2: RESEARCH AND RECOVERY STUDIES ON THE SAN JUAN RIVER HISTORICAL STUDIES No comprehensive studies of fish presence, abundance, distribution, or life history were conducted on the San Juan River until the late 1980s. Earlier studies are generally only usable to determine fish presence. The earliest accounts of fish in this area were from a U.S. Army geographic and geologic expedition to portions of the West during the early 1870s (Wheeler SUlVey): specimens collected by the expedition were identified by ichthyologists at the National Museum in Washington, D.C. (Cope and Yarrow 1875). Much of the early fish collections from the western United States came from similar explorations, and it was common to have mistaken location information for the specimens when they arrived at museums in the East. The first ichthyologist to actually visit much of the West was David starr Jordan, the father of modem ichthyology in the United States, who was familiar with many of the fishes of the West from examining museum specimens. Jordan visited the Durango, Colorado, area in 1889 and sampled some of the streams there. As was his standard practice, he visited with local residents regarding fish they caught in the rivers and streams, and these conversations provided valuable information on historic native fish distribution and abundance (Jordan 1891). His collections from small streams verified the presence of cutthroat trout (Onchorynchus clarki), speckled dace (Rhinichthys osculus), bluehead sucker (Pantosteus discobolus), and mottled sculpin (Cottus bairdi), native fishes of cooler streams. Local residents told him about fish they caught for food, including tlannelmouth sucker (Catostomus latipinnis), razorback sucker, and Colorado pikeminnow. Area residents indicated that Colorado pikeminnow and razorback sucker ascended the Animas River, apparently to spawn in the spring. These larger fish were generally well known by local residents of the Colorado River Basin because they were important in their diets, along with native trout (Jordan 1891). Jordan's accounts of razorback sucker and Colorado pikeminnow, although they are secondhand, are the first authentic accounts of these species in the San Juan Drainage. Based on what is known about the distribution and abundance of razorback sucker and Colorado pikeminnow today, the fact that these species were known by local residents and were common enough to be caught in the Animas River, a cool tributary, suggests they were likely common in the San Juan River. Platania (1990) summarized museum specimens and collections in the San Juan Basin from 1900 to 1960. Of the several collections made by state fish and game biologists, most were either from the upper portion of the river near the present site of Navajo Reservoir, or from scattered collections at access points such as Mexican Hat, Utah (Figure 2.1). Most of these specimens were adults since collection techniques included angling and other methods targeting adult fish. Even September 2000 2-1 Program Evaluation Report