| The Magazine of the CALIFORNIA ACADEMY OF SCIENCES |
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Habitats Evolutionary Jackpot Flight 259, departing Oakland 1:30 p.m., arriving Las Vegas 3:45 p.m. I have asked especially for a bulkhead seat so I can stretch my legs while I read the file I've put together about my destination, Ash Meadows National Wildlife Refuge. But facing me, on the other side of the legroom, are three of the loudest, most "fun loving" people I've ever met. The two young women in jeans, nails, and cowboy boots, and the older man whose belly button peeks out from under his sweatshirt, were drunk when they boarded and they toss back little bottles of scotch as we fly. They are yucking it up with the stewardess, teasing and tickling each other, making defective origami creatures with pages torn from the inflight magazine and little hats made out of vomit bags. They will be spending the weekend in Las Vegas. I'm drinking orange juice and feeling curmudgeonly as I try to concentrate on the file that sits open in my lap. A little origami football lands in my folder. "Sorry!" says one of the women. "Hey, are you going fishing?" She's seen the pupfish on the cover of the Fish and Wildlife Service pamphlet I'm reading. "No. All the Devils Hole pupfish in the world wouldn't make a meal." "Where are they?" she asks. "They live in a desert cave in Ash Meadows, about 90 miles northwest of Vegas. They're endangered." "Endangered *)&%$#! Species Act! I've been out there," the man says. "We've been riding out there on our trikes." He imitates a motorcycle ride, complete with sound effects, and the three of them start laughing again. Out the window I see only desert, but then, as the plane dips into its descent, an island of glistening buildings appears from nowhere. I have heard a lot about the excesses of Las Vegas, but my wildest expectations are exceeded by the reality. As I walk down "the Strip," I'm engulfed by an ocean of lights swirling and pulsing up the sides of buildings and marquees broadcasting promises of beef, busts, and bucks. Inside, the casinos are like sunless, underground ant colonies teeming with urgent, exotic business. Somewhere, the hidden queen is being bathed in the money brought in by the countless, driven workers. (Vegas gets more than 20 million tourists, and local casinos gross more than four billion dollars, a year.) Outside, I'm accosted from every direction by men handing out catalogs advertising local prostitutes. Las Vegas is a schizophrenic episode. And it is probably the fastest growing city in America, drawing five thousand new residents a month. If the city has a tertiary theme (after sex and money) it is wetness. Water is everywhere; running through the lobbies of hotels, roiling in huge casino fountains, filling countless swimming pools, and spraying shamelessly over giant lawns. Next morning I'm up and checked out of my motel at 5:30 and driving toward Ash Meadows. In the light of morning the Strip looks deflated, like a spent condom. Only those still unsatiated with gambling, drink, or whoring are awake at this hour. A few miles out of the city I turn onto highway 160 and everything changes. Desert scrub, dotted with blooming Joshua trees, their arms thrust in the air, extends to the horizon. Breathing becomes easy again as I drive into the open space. An hour and a half and 90 miles later I turn onto a gravel road and roll past the sign I've been waiting for: Ash Meadows National Wildlife Refuge. Ash Meadows is most famous as the home of the Devils Hole pupfish (Cyprinodon diabolis). In the 1970s, the pupfish captured national attention as attempts to protect it led environmentalists and local agricultural developers to a bout in the U.S. Supreme Court. The fish, which has lived in one small pool for about 50,000 years, was endangered by nearby groundwater pumping, which nearly eliminated its habitat. In 1976 the Supreme Court decided in favor of the fish and limited the amount of groundwater that nearby farmers could pump from the basin supplying Devils Hole. This was a landmark case for the Endangered Species Act because of the distance between the regulated activity and the threatened species. The court confirmed that landowners were accountable for the damage that actions on their property might do to endangered species elsewhere. I have wanted to come to Devils Hole for many years. If Ash Meadows is an island oasis in the Mojave sea, Devils Hole is an island within that island. For 50,000 years the pupfish has lived here, in this 70-by-10-foot hole (the smallest range of any known vertebrate species), in complete isolation from any other fish species. Their population has probably never exceeded 1,000. These days it hovers between 200 and 500, fluctuating with the seasons, each fish living only about eight months. Devils Hole is a window on the aquifer underlying the area. It lies at the bottom of a 30-foot-deep fissure in the side of a mountain and is completely isolated from any other above-ground water sources. In isolation, the Devils Hole pupfish has climbed its own evolutionary branch, surviving without predators and living on the algae that grow on the one underwater sun-lit ledge in this cozy cave. In 1952 the federal government decided to make Devils Hole a part of Death Valley National Monument, even though the eastern border of Death Valley is 40 miles to the west and on the other side of the state line. So today, a 40-acre island of national park (the passage of the Desert Protection Act last year turned Death Valley into a national park) sits in the middle of the National Wildlife Refuge: a unique arrangement as far as I know. Beth and David St. George, the wildlife biologists under whose care the entire 23,000 acres of refuge falls, drive me to Devils Hole from the refuge headquarters. We climb around the side of the barbed-wire-lined fence and down some rickety steps to a locked gate. "Watch the third rung on the ladder, it's broken," says David as we climb down an old wooden ladder to the bottom of this strange crack in the ground. There we find the famous pool: a sort of Mecca for lovers of rare species. I stare at it for a moment, but see only the sky. Suddenly the pupfish appear, swimming as enthusiastically as their name implies. On our way out, I ask the St. Georges the reason for such high security and David answers: "Two reasons. First, the cave used to attract divers from all over. They sometimes dove as deep as three hundred feet. In the 1960s a party of three divers went down, and only one returned. The other two are still trapped down there somewhere. Now the only divers allowed in the cave are the guys who do the population count every other year. "The second reason is that one balloon filled with bleach tossed into the pool could wipe out the entire wild species in a couple of minutes." The Devils Hole pupfish is the most famous occupant in Ash Meadows, but it is not the only interesting or rare inhabitant. In the hours that follow our visit to Devils Hole, the St. Georges and I drive and hike around the refuge looking at one endemic plant or creature after another. Ash Meadows has the highest concentration of endemic taxa anywhere in the United States. Twenty-four Ash Meadows plant and animal species are found nowhere else on Earth. Twelve of these are listed as threatened or endangered and another twelve endemic species are now candidates for listing. About 12,000 years ago, at the end of the Pleistocene Ice Age, this area, and much of the Southwest, was covered by a network of interconnecting lakes and river systems, the products of melting ice sheets. But by 10,000 years ago the waters had retreated leaving only arid desert behind. Well, almost.
The ancestors of the beautiful Amargosa pupfish (Cyprinodon nevadensis mionectes) were stranded here. As were those of the Warm Springs pupfish, Ash Meadows speckled dace, Ash Meadows naucorid, Ash Meadows blazing star, Ash Meadows ivesia, Amargosa niterwort, spring-loving centaury, Ash Meadows sunray, Ash Meadows milk vetch, the Ash Meadows gumplant, and others. We head out to Longstreet Springs, where the Amargosa pupfish lives. Jack Longstreet settled here in 1889 and, diverting water from the spring, tried mining and raising horses for ten grueling years. He married a local Paiute woman, and was an advocate for the rights of the local natives. Today, all that remains of their occupation is a brick wall, about 15 yards from the swirling pool that is Longstreet Spring. A few miles from Longstreet is Crystal Spring. It is early spring and the male Amargosa pupfish are beginning to turn bright blue. This species of pupfish is doing relatively well here, and is found in a number of the refuge's 30 seeps and springs. Beth St. George says they are expecting it to be downlisted from endangered to threatened (a ceremony the Devils Hole pupfish, because of its intrinsically limited habitat, will never enjoy.). It is hard keeping visitors to the refuge out of the spring, and it's easy to see why. The water is a kind of deep eye- blue and crystal clear. It spins around and around and with it swirl large mats of algae that look like giant dreadlocks. In the bottom of the pool, swaying silently, are more clumps of algae next to the vent through which the water enters. More than 2,600 gallons of ancient water shoots into the pool every minute. It comes from a vast aquifer that stretches nearly to Las Vegas. A fault forces these deep, groundwater sources to the surface here. All of the water at Ash Meadows is "fossil" water, believed to have entered the groundwater system somewhere between 6,000 and 11,000 years ago. The gurgling, crystal water appears ecstatic to be back on the surface after all that time in the dark. The water feeding the desert springs flows out of them just as quickly. Before white pioneers came here just over a hundred years ago, these outflow streams fed what was then the largest marshland in southern Nevada, Carson Slough. Here the various populations and species of pupfish and other fishes mingled. And here have evolved other species, some now extinct, like the Ash Meadows poolfish, last seen in the 1940s. With the coming of settlers, such as Longstreet, many of the springs were channeled and their water diverted for growing alfalfa. And in the early 1960s the marshland was destroyed by peat mining. The St. Georges are hoping to return the springs to their natural flow and restore Carson Slough to its original marshy state. It will be a big job, though: their budget is small and the refuge's staff consists of the two of them, a refuge manager, and a maintenance worker. And, David says, budgets threaten to shrink still further. Not only are they responsible for implementing the recovery plans at Ash Meadows, but they also police the place and care for visitors. As David tells me this, he gingerly leans over and picks up three empty cartridge shells off the ground. From Crystal Spring we follow the runoff channel a little ways and see a tiger beetle, a woodhouse toad, an exotic crayfish. A Cooper's hawk flies overhead. Despite the damage done to the refuge, two hundred species of birds still use the water sources here as welcome stopping points on their long migrations. If the slough is ever restored, the refuge will attract many more geese and ducks and loons and ibis. In addition to the damage done by settlers to the hydrology of the refuge, the wildlife here also suffers from the competition of aggressive outsiders. Some of the pools have bass, brought here by fishermen in the 1970s. Large crayfish also plague the Amargosa pupfish. Exotic salt cedar thrives here, tapping water with its deep-reaching roots and concentrating salt on the surface, where it inhibits the life cycle of other native plants. But by far the greatest threat to this miraculous place comes from Vegas, which in recent years has been vying for control of water in counties as far as two hundred miles away, including rights to ground- water connected to Ash Meadows. In 1989, after a flurry of protests and notification from four Department of the Interior divisions (BLM, FWS, BIA, and NPS) that they would try to block the move, the Las Vegas Valley Water District shelved the proposal. The filings are still in the State Engineer's office, however, and, according to sources at the Fish and Wildlife Service, Interior is still preparing to go to court against Las Vegas if they are resubmitted. "The carbonate aquifer system that feeds Ash Meadows is very deep and complex and there are still many groundwater flow paths that haven't been identified yet," says Patty Fiedler, a hydrologist at the Fish and Wildlife Service. If Vegas gets rights to a neighboring county's water, it may well end up having an unexpected effect on Ash Meadows. Meanwhile, Las Vegas is looking for other ways to satisfy its unquenchable thirst, including increasing its allocation of water from the Colorado River. Failing that, however, the city may see no choice but to reapply for the rural groundwater supplies, challenging again the Endangered Species Act's ability to protect a small and delicate habitat from the march of progress. "You can't take a community as thriving as this one and put a stop sign out there," says Patricia Mulroy, general manager of the Southern Nevada Water Authority. By the time Vegas is reapplying for Ash Meadows' groundwater, if it comes to this, and if the new Congress has its way, the courts may be interpreting a very different Endangered Species Act, one which requires economic impacts to be weighed against environmental gains when deciding how or whether to implement the law. I consider the value of the Devils Hole pupfish, and that of a waterfall in a new casino, and I wonder who will do the weighing. That evening the St. Georges leave me alone on the refuge. As they drive away, the place is slowly consumed by a sunset so lovely and vast that it dwarfs even the garish memory of Vegas the night before. Gordy Slack is Associate Editor of California Wild. |
Summer 1995
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