Van Dyke, F.G. and R.H. Brocke. 1987. Searching Technique for mountain lion sign at specific locations. Wildlife Society Bulletin, 15(2):256-259.

Abstract: The eastern mountain lion (Felis concolor couguar) has been considered an extinct subspecies since the turn of the century (Young and Goldman 1946). Apparent sightings of mountain lions in eastern North America continued after the subspecies' supposed demise. Several investigators (Wright 1959, Sealander and Gipson 1973, Culbertson 1977, Yenke 1982) used such reports to assert that lions were extant in New Brunswick, Arkansas, Great Smoky Mountains National Park, and Louisiana, respectively, although such reports were not substantiated by physical evidence. Sighting reports like these contributed to the listing of the eastern mountain lion under the Endangered Species Act of 1973 (Public Law 93-205), even though no populations could be located.

An objective method of assessing lion presence at specific locations where lions have been reported has not been available. to aid in resolving questions about the status of mountain lions in the East and in other areas where their existence is presumed because of sightings, we developed an index to evaluate the reliability of sightings. Development of the index entailed determination of the type and amount of physical evidence, especially tracks, left by mountain lions where they were known to have been at specific times.