Federal officials have identified more than 5,500 acres high in the Spring Mountains as critical habitat for the endangered Mount Charleston blue butterfly.
The proposed designation is aimed at defining and protecting open areas known to harbor the rare butterfly, its host plants and the flowers it feeds on.
The critical habitat is in three separate blocks totalling 5,561 acres at the top of Kyle and Lee canyons and along the road connecting the two, state Route 158, near Fletcher Peak. The largest of the three areas takes in a stretch of state Route 156 in Lee Canyon and portions of Las Vegas Ski &Snowboard Resort.
The U.S. Fish &Wildlife Service will detail the proposal in a Federal Register notice set for publication today. The public will have 60 days to comment on the designation.
Roughly 99 percent of the habitat is on federal land, and most of it is already protected as wilderness. The 1 percent that isn’t includes a few residences and some Clark County land, but no new restrictions will be placed on those areas, said Dan Balduini, spokesman for the Fish &Wildlife Service in Las Vegas.
“It’s private property. They can go about their business,” he said.
The designation isn’t expected to change much on federal land either. “It doesn’t close them to entry,” Balduini said.
Already those areas are off-limits to butterfly collection, but the bigger threat to the blue and its habitat has come from recreational development and decades of wildfire suppression work that has produced overgrown forest.
The butterfly’s decline in recent years is blamed in part on a U.S. Forest Service fuel-reduction project that saw small trees and brush cut down, chipped and spread on the ground, effectively burying the blue’s host plants and larvae.
The Mount Charleston blue is a distinct subspecies of the wider-ranging Shasta blue butterfly. It was added to the endangered species list in September after conservationists pushed for its protection.
“Saving the Mount Charleston blue butterfly will preserve an essential piece of the natural world that makes life on Earth more beautiful and interesting for all of us,” said Tierra Curry, a senior scientist for the Center for Biological Diversity, a Tucson, Ariz.-based environmental group that has sued the Fish &Wildlife Service over endangered species protection.
The exact population is not known, but there could be fewer than 100 Mount Charleston blues left in existence.
The proposed habitat designation comes as a research team from UNLV wraps up work on a four-year study of the elusive butterfly that only takes wing for about two months each year. At less than an inch long, the males are iridescent blue and gray, while the females are a more subdued brown-gray.
The study led by biology professor Daniel Thompson is slated for release later this summer. It also looks at other species of butterfly only found in the Spring Mountains.
The Fish &Wildlife Service said a copy of the proposed critical habitat designation would be available online at www.fws.gov/nevada. Comments on the proposal will be accepted electronically or by mail through Sept. 15.
The service will hold an informational open house on the habitat designation from 6 p.m. to 8 p.m. Aug. 19 at the Las Vegas office it shares with other federal agencies at 4701 N. Torrey Pines Drive.
Contact Henry Brean at email@example.com or 702-383-0350. Follow @RefriedBrean on Twitter.