Rails are secretive birds of wetlands and though the Park does not have much wetland habitat, it is possible that all of the rail species on the Park list are at least somewhat more common than observations indicate, especially in Cades Cove. Most of the Sora observations have come from the Tennessee side of the Park and most have been dead or wounded birds, a condition that under certain circumstances makes them more noticeable than when they are alive and able to scurry away under cover of vegetation.
Park Naturalist Arthur Stupka (1963) noted seven records, all from the fall (September through early November), and many brought down into the Park by sever weather events in the Park Headquarters area and along the Newfound Gap Road. More recent sightings are of live animals during May (1996) in restored wetland habitat in Cades Cove, including an individual heard calling on May 26, and a live bird in early May (2004) near the Oconaluftee Visitor Center, as well as a live birds in a fields at Purchase Knob at 1,400 meters elevation and in Cades Cove (October 2006; P. E. Super and S. Hoyle).
References:
Stupka, A. 1963. Notes on the Birds of Great Smoky Mountains National Park. University of Tennessee Press, Knoxville.
Gough, G. A., Sauer, J. R., Iliff, M. Patuxent Bird Identification InfoCenter. 1998. Version 97.1. Patuxent Wildlife Research Center, Laurel, MD.