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<br /> <br />1 <br /> <br /> <br /> <br /> <br /> <br /> <br />1 <br /> <br />Mapping <br />Collection localities and range notes from museums and state natural resource agencies, <br />regional fish experts, and literature sources were entered into a Microsoft Access <br />database to help assess regional trends in distribution and abundance. Maps were created <br />using ArcView (V3.2). Base map layers were obtained from Kathy Fenton of the U.S. <br />Bureau of Reclamation, Denver, and the Environmental Protection Agency (EPA, <br />www.epa.gov). Methods used to consistently map collection locality data are described <br />in the following section. <br />Data reliability ranking-Data sources vary in their reliability of species <br />identification (Bestgen et al. 1995). To examine the potential effects of data reliability <br />on the distribution maps, data sources and their associated collection records were split <br />into two categories, those with voucher specimens and those without. Existence of <br />voucher specimens was subjectively determined from known museum and lab holdings, <br />and descriptions of voucher specimen collection in the literature examined. Museum <br />collection records that did not meet our standards for database QAQC were not <br />considered as having voucher specimens. Distribution maps were generated with two <br />sets of collection data, one including all records and another with only the voucher <br />specimen-backed records. <br />Classification of locality data--Geographic specificity of locality data varied <br />' from descriptions of lengthy river segments to written descriptions of point locations to <br />specific geographic. coordinates. To simplify mapping efforts, locality data were divided <br />' into point and range data categories. Point data (geographic coordinates, river mile <br />locations, and specific geographic locations, i.e., mouth of Paria River) were mapped as <br />' points on the distribution maps. If range descriptions (i.e., the Colorado River from Rifle <br />to Silt) were less than 20 km long, range data were also mapped as points (approximate <br />' mid-point of the range). <br /> <br /> <br />Final Report September 2002 <br />11 <br /> <br />