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~ ~. Prior collections indicated that field indentification of Gila spp. was diddicult. Therefore, specimens collected at Coal Creek were transported to Vernal for use in evaluating all known methods of species identification. Different morhpological counts and measurements presented by various authors (Smith et al 1979; Minckley 1973) were made on live and pre- served specimens. Taxonomists and knowledgeable field workers were also contacted during the interpretation of the results of this work.' In addition, selected specimens were sent to noted authorities for identification. Although all specimens were not sacrificed, a cm grid board was utilized for photographing all Gila spp. for future study. During one collection trip, fin tissue was taken from all collected Gila spp. and shipped to Arizona State University for electrophoretic analysis. Sacrificed specimens were subjected to a taxonomic study. Speci- mens were x-rayed and vertegral counts were made. Eight meristic characters and gross morphological shape- were used to segregate species. These characters were weighed according to their merits for species segregation since considerable overlap occurs bwtween species for part- iclar meristic characters (e.g. precaudal vertebrae counts for G. c pha and G. robusta). Meristic characters exhibiting the least overlap were weighed more than those with considerable overlap as follows: Character Weighing Factors 1. Mouth, whether terminal or inferior 2 2. Eye diameter 1 3. Gill rakers counts on second arch 4 4. Precaudal vertebrae 2 5. Dorsal and anal fin ray number 1 10 Totals 6. Head length divided by cuadal peduncle depth 3 7. Caudal peduncle length divided by head length 2 8. Total vertebrae count 5 10 Totals Characters 1 through 5 gave the best separation into the three species. Characters 6 through 8 were utilized to separate G. cypha from G. elegans if meristic characters 1 through 5 did not segregate the two. Four Vernal FWS fishery biologists then participated in the identi- f ication of specimens and a score sheet was compiled for each specimen. A specimen that received 7.5 out of 10 points (75y) was required in order to classify a specimen into one of the species; less than 7.5 was considered an unknown.