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<br />Ranges longer than 20 lcm were mapped as continuous, shaded segments on the <br />distribution maps of all three species. To fill in gaps in range data coverage, point <br />' collection locations were spatially transformed to range data using the reach associated <br />with each collection point (river reaches were determined from the EPA's RF1 file, <br />' which was used as the stream layer for distribution maps). A species may not occur in <br />the entire shaded reach as shown due to this transformation, and/or presence of <br />unsuitable habitat, migration barriers, etc. in the mapped reaches. Overall, the high <br />density of point data suggested that such reach mapping errors would be minimal. <br />' It is important to note that collection points on distribution maps only provide <br />information about spatio-temporal distribution of sampling effort and associated fish <br />capture, and should not be interpreted to represent fish abundance. Points only mean that <br />an unspecified number of a study species were collected at that location on a particular <br />date. However, repeated collection of a species at a point or within a certain river reach <br />may mean that the area is often occupied or traversed by that species. Alternatively, <br />' repeated collection of a species at a point or within a certain river reach may mean that <br />the area is often sampled. <br />Of the roughly 25,000 collection records gathered during this study, approximately <br />15,000 came from records of specimens catalogued in the fish-collection database of the <br />LFL. The CRB portion of the LFL fish-collection database includes collections from <br />1980 to the present, with locality records available from a large portion of the UCRB <br />including the mainstem Green and Colorado rivers in Utah and Colorado, and tributaries <br />' such as the Yampa, White, and Gunnison rivers. <br />' Approximately 2,300 point collection records were generated through examination of <br />literature sources. Literature-based point collection records covered years 1853 to <br />present and were widely scattered throughout the C12B. Additional records were mapped <br />from fish collection databases at Arizona State University, Cornell University, Humboldt <br />' State University, the Illinois Natural History Survey, the Tu1ane University Museum of <br /> <br />Final Report September 2002 <br />1Z <br /> <br />