The National Park Service explained its decision in the following news release:
In 2007 Buffalo National River created three "dogs allowed" hiking trails in the park so that visitors would have the opportunity to exercise their pets while enjoying a walk. These trails were Eden Falls (Lost Valley), Mill Creek (off Highway 7 near Pruitt), and the Forest Pit Trail (Buffalo Point Campground).
Despite opposition from some, the decision was made to proceed on an experimental basis in order to evaluate the impacts on visitors and park resources. This appears to have been a success with the exception of the Lost Valley trail where a combination of factors has convinced park management to reverse its decision.
Lost Valley is one of the two most heavily used hiking trails in the entire park, vying with the Panther Creek/Indian Rockhouse trail near Buffalo Point in popularity. Visitor feedback has been largely negative relative to the presence of dogs here, ranging from complaints that many dog owners do not keep their pets on a leash, to congestion in the upper areas of the trail where dogs (leashed and unleashed) cause tripping hazards where the trail is steep and narrow. There has been, not unexpectedly, a noticeable increase in dog waste along the trail. There has also been one documented incident of an injury stemming from an unleashed dog when a small boy was bitten on the chest.
The Superintendent's Compendium is the vehicle by which these management decisions are implemented and can be found at http://www.nps.gov/buff/parkmgmt. This document also includes other regulations pertaining to dogs throughout the park. Visitor cooperation and adherence to these policies is greatly appreciated.
Buffalo National River continues to provide a wide variety of recreational activities for all visitors. While it is our desire to give park visitors the safest and most enjoyable opportunities to experience all the park has to offer, we must continue to evaluate uses based on the impact on resources, the compatibility to the park's purpose and mission, and visitor safety.