Authorities have dubbed an area they've set aside for an endangered species of fish the "Warm Springs Natural Area" to reflect its role as a haven for the Moapa dace and other sensitive species.
The Southern Nevada Water Authority and the U.S. Fish and Wildlife Service are protecting nearly all the natural habitat of the Moapa coriacea, a finger-length fish with a black spot in the middle of its tail that is on the federal endangered species list.
The water authority holds the largest piece of property, a roughly 2,000-acre tract dotted with natural springs and imported palm trees that researchers believe is home to almost all the dace on Earth.
The name was changed after the Las Vegas-based authority took control of the property known as Warm Springs Ranch, 60 miles north
of Las Vegas, in September.
It is the site of springs of prehistoric water from a deep carbonate aquifer that bubble to the surface at dozens of sites and form small streams that come together as the Muddy River.
The Moapa dace spawns in warm spring pools and makes its home in streams and upper reaches of the river's main stem.
The entire habitat of the fish is confined to an area just a few miles long,
so officials say even a minor threat could prove fatal to the species.
The authority eventually plans to develop a comprehensive management plan for the area.
First, though, officials must take stock of their new property.
Janet Monaco, who heads the authority's Muddy and Virgin River Division, said a complete inventory is in the works for the 1,179-acre ranch once owned by Howard Hughes.
The property includes a bath house, a large, spring-fed swimming pool with its own paddle boats, and some cabanas rumored to have been used as a tanning spot for Las Vegas showgirls.
Much of that stuff likely will be removed to return the property to its natural state, Monaco said.
Cattle grazing on the property also are expected to disappear once the current ranching lease expires in March.
Monaco said overall goal of the management plan is to create the best possible habitat for the dace and other sensitive species of fish, birds and insects.
A hint of how that might be done can be found across the road from the natural area at the Moapa Valley National Wildlife Refuge, a federal preserve originally established on 32 acres in 1979.
The refuge now includes 117 acres of old ranch and RV park property that the Fish and Wildlife Service manages as part of the 1.6 million acre Desert National Wildlife Refuge Complex in Clark, Lincoln and Nye counties.
Refuge officials have spent the past several years tearing out swimming pools and thinning crowded stands of palm trees that, left
unchecked, can choke streams and invite damaging wildfires.
Wildlife managers also are eliminating nonnative fish species that can crowd out the dace.
In the early 1990s, tilapia, a nonnative game fish, found its way up the Muddy River and began feeding on the natives.
The dace population plunged from about 3,400 to fewer than 1,000 in just a few years.
Those numbers are on the way back up.
The last official count in February, found 1,172 Moapa dace living at the headwaters of the Muddy River.
The Moapa Valley refuge has no full-time staff and is closed to the public.
Officials hope to eventually allow some bird watching, but say visitor access likely will be limited to protect the dace.
The property was purchased with nearly $69 million in grants from the Southern Nevada Public Lands Management Act, which uses proceeds from the sale of federal land in the Las Vegas valley to fund conservation and recreation activities in the region.
The water authority began taking a lead role in the protection of the dace as part of a 2006 federal agreement with water users in the area.
The deal cleared the authority to begin tapping the nearby Coyote Spring Valley, where the agency has rights to enough water to supply about 20,000 Las Vegas area homes.