Officials will close Parunuweap Canyon - a popular southern Utah hiking spot - to study the impact visitors have on native plants and animals.
Park Superintendent Don Falvey said the area will be closed for the rest of the 1992 season, and when it is reopened, it might be designated as a Research Natural Area."Parunuweap is being used as a control experiment," said park back-countryranger Ralph Moore. "It's our barometer for monitoring change within the park."
If the area is designated as a research area, it would be permanently closed to hikers.
Park officials said the closure might be necessary as part of the National Park Service Act of 1916.
Park resource management specialist Vic Vieira said natural resources have to be preserved for scientific research, even if it means closing them to recreation.
There are three other research areas in the park.
Officials said last year there were 35 back-country permits issued for Parunuweap Canyon.
The area contains possible habitat for such rare and sensitive species as the peregrine falcon, Virgin River spinedace and desert bighorn sheep and is possibly a dispersal corridor for the Mexican spotted owl.
"It may be an all-or-nothing deal," said Vieira.
Falvey pointed out, however, there could be a wide number of proposed alternatives, with the most restrictive scenario, in terms of visitor use, amounting to a complete closure from park boundary to park boundary.
"We don't want to arbitrarily limit visitor use," said Falvey, "but if it impacts the resources, that may be the only alternative," especially, he added, when the mission is to first protect the resource and secondly, provide for the public's enjoyment.
"It think it's important," added Moore, "something be done fairly soon to protect this area. This may be our last canyon in the park to be preserved in a relatively wild condition."