Boom, Boom on the Range
Biologist John Hervert, arguably the world's foremost expert on the Sonoran pronghorn antelope, hoists an antenna in his left hand and listens to a receiver for blips indicating whether any radio-collared pronghorns are nearby. He hears nothing but static.
Before him stretches the xeric wilderness of the Growler Valley, a 10-mile-wide alluvial trough in southwestern Arizona devoid of anything manmade. No buildings, no roads, no cars, no glint of glass, no power poles, no smog--just a low, khaki forest of creosote and white bursage interrupted by clumps of paloverde and mesquite.
Hervert is not surprised that no pronghorns are detected. They are, after all, rare, endangered and scattered over millions of acres.
Hervert, 40, works for the Arizona Department of Game and Fish. He has devoted much of the past five years of his life to studying the phantom antelope, which, capable of speeds exceeding 70 miles per hour, is the swiftest land animal in the New World.
Hervert has traced pronghorn movements with radio and satellite telemetry, he's counted them from airplanes, he's donned camouflage to creep up on them, he's watched does give birth, he's captured them with nets dropped from helicopters, he's made photographs of them using infrared sensing devices.
When one of his radio-collared pronghorns dies--and an alarming number, 14, have died in the past two years--he pores over the remains, provided any can be found.
"Coyotes on the edge of starvation eat everything--everything," he explains. "They chew up all the bones."
Some estimates put the Sonoran pronghorn population at upward of 200, but Hervert figures no more than 140, and possibly as few as 80, survive in the United States, with an equally vague number across the border in Sonora. They live in one of the most forbidding environments on the planet.
Their parched habitat also lies beneath the U.S. military's second-largest aerial training site, the 2.7 million-acre Barry M. Goldwater Gunnery Range. It's where Top Gun pilots hone air-to-air combat skills and make bombing, strafing and missile runs on mock airfields and convoys.
Hervert's job is to help figure out how the Sonoran pronghorn can be preserved, and eventually removed from the Endangered Species List. The means to that goal are the subject of intense debate which, distilled to its essence, pits the fate of one timid mammal against the future of the Free World.
Hervert finds himself in the middle of a high-stakes scrum. Government agencies are at odds with conservation groups and often with each other. Lawyers are involved.
And Hervert is worried. Although Sonoran pronghorn are uniquely adapted to survive in their habitat, the drought that gripped the Southwest during the winter of 1995 and into 1996 appears to have taken a heavy toll on them. Predation, especially from coyotes, seems to be increasing. No fawns born in the spring survived the summer.
"I believe the likelihood of extinction is all too real for Sonoran pronghorn," Hervert says. "It won't take very many years of drought in a row for them to disappear."
Hervert is no tree-hugging alarmist. He's a well-educated man, a scientist who knows that management of any species must be based on solid research.
But he's as tough as the desert terrain. He's a plain-spoken game warden who wears a uniform, a sidearm, wraparound shades and the aura of confidence in his own survival skills.
So when he says that extraordinary measures are needed to save the Sonoran pronghorn, he speaks with credibility.
And that, perhaps, is why the U.S. Department of Justice tried to stop John Hervert from testifying that the Air Force could conceivably bomb the endangered Sonoran pronghorn back to the Stone Age, or beyond--all the way back to a time when the species didn't exist.
There is no evidence that military activity has ever killed or injured a Sonoran pronghorn--although in a place where no protein goes wasted, there's no guarantee any evidence could be found.
There is also little doubt that Barry M. Goldwater Gunnery Range, established in 1941, has over time had the effect of insulating the Sonoran pronghorn and other wildlife found there, including the endangered lesser longnosed bat. Luke Air Force Base administers the gunnery range.
The gunnery range overlays most of the 860,000-acre Cabeza Prieta National Wildlife Refuge. The rest of the range covers property owned by the federal Bureau of Land Management. The range abuts the 330,900-acre Organ Pipe Cactus National Monument, which is administered by the U.S. Park Service.
Most of Cabeza Prieta and Organ Pipe are designated wilderness areas. Combined with the gunnery range, they keep three million acres of mostly pristine desert off-limits to such destructive forces as grazing, off-road vehicles and development in general.
While F-16 and A-10 jets prowl the skies above much of the pronghorn habitat, the Air Force says only 5 percent of the landscape is actually marked by military operations. The range contains roads, simulated combat targets such as airfields, control towers, hangars and other buildings. Pilots in training take aim at fake formations of tanks and mock railroad yards with trains.
The vast majority of the 50,000-plus sorties flown over the range each year involve delivery of ordnance that's not highly explosive. Upon impact, these projectiles merely emit a puff of smoke or a flare, enabling supervisors to rate a trainee's accuracy. These "inert" bombs do litter the landscape, but portions of the range are closed periodically so they can be collected.
There are, however, three areas on the range where live ordnance--including 1,000-pound bombs and Maverick air-to-ground missiles--is used. It is in one of these areas, at a place called High Explosive Hill, where John Hervert and Laura Thompson-Olais, a Fish and Wildlife Service ecologist, noticed pronghorn were congregating.
"During our telemetry flights of the spring and early summer of '95," Hervert says, "we saw some pronghorn near H.E. Hill, and we pondered why the pronghorn were there, because they seemed to be there in frequency greater than random groupings of animals.
"During one of those flights, we spotted the water hole."
The water hole actually is a massive bomb crater, 30 feet across, blasted into an area where rainwater collects. An underlying layer of clay keeps the water from seeping away. The crater is deep enough--Hervert says the water has been as deep as seven or eight feet--to retain water for months at a time.
Although it hasn't rained on the range in weeks, the crater contained water last week when Luke officials took New Times for an inspection of H.E. Hill and the crater.
Water isn't the only thing that lures pronghorns to High Explosive Hill. Soil in the pronghorns' habitat is so hard-baked it's called desert pavement. But explosions at H.E. Hill apparently loosen the soil, allowing seeds that otherwise would dry up and blow away to sprout, producing forage.
The irony that weapons of mass destruction might indirectly nurture an endangered species is not lost on those charged with its recovery.
But neither is the threat to that species. It doesn't take a Ph.D. in biology to recognize that endangered species and high explosives don't mix.
Except for two months each year when H.E. Hill is closed for cleanup, the site absorbs 150 to 250 bombs per month, including 1,000-pound bombs, rendering it a pocked moonscape of pulverized, volcanic cinder.
Major James "Jake" Alwell, a flight instructor and No. 2 officer in Luke's Range Management Office, says H.E. Hill teaches pilots the dangers of friendly fire. He says shrapnel from a 1,000-pounder can fly 2,500 feet from the point of impact, so pilots are trained to keep their distance and time their own bomb drops so as to avoid the explosive "bubble" left by a preceding warplane.
Standing more than a quarter-mile from H.E. Hill last week, Alwell picked several footlong fragments of bomb casings that blanketed the ground, held them up and explained that such shrapnel could easily bring down an F-16.
Or, presumably, an antelope.
Biologists charged with preserving an endangered animal such as the Sonoran pronghorn face a conundrum. The fact that there are so few of the species makes it risky, at best, to capture and collar them, or even observe them closely.
Yet without scientific study, it is difficult to know whether--and why--their numbers are increasing or decreasing.
A dearth of data produces disagreement over the most basic pronghorn facts. One biologist might say the species is on the verge of extinction, for example, while another may postulate that since nobody has ever known the true population, it cannot be said with scientific certainty that their numbers have declined.
Consequently, one of the most pressing tasks facing the biologists charged with recovery of the Sonoran pronghorn (to a "sustainable population" of 300 in the U.S.) is getting a good idea how many of them exist now. This is done painstakingly, if not precisely, by aerial survey, with spotters in single-engine planes flying a grid pattern over their massive range.
John Hervert and U.S. Fish and Wildlife Service officials also take weekend flights over the range--when no warplanes are about--to track movements of radio-collared Sonoran pronghorn.
The species has been listed as endangered since 1967, yet has shown no apparent recovery in nearly 30 years. Much remains to be learned, but here is some of what is known about the enigmatic ungulate:
Its Latin name is Antilocapra americana sonoriensis, one of five subspecies of Antilocapra, all of which live in North America. Other subspecies of Antilocapra exist in Arizona (americana americana and americana mexicana), but they are not endangered.
Travelers on Camino del Diablo, the treacherous frontier trail that linked Caborca, Mexico, and Yuma, told of seeing hundreds, even thousands, of pronghorn en route. During a border survey conducted in the 1890s, Sonoran pronghorn were observed in every valley between Nogales and Yuma. Old-timers recall ranchers chasing Sonoran pronghorn into pens, then challenging their greenest wranglers to lasso them.
Today, the Sonoran pronghorn's territory is much smaller and more fragmented than it once was. Its current range is bounded roughly by Interstate 8 on the north, Caborca on the south, the Lechugilla Desert on the west and U.S. Route 85 on the east.
Two former free-flowing sources of water and accompanying forage--the Gila River to the north and Rio Sonoyta across the border in Sonora--now flow intermittently due to dams and diversions for agriculture.
But the drying of those rivers and the decimation of their riparian areas do not necessarily sound a death knell for the Sonoran pronghorn. As deserts go, the Sonoran is capable of supporting a veritable riot of flora and fauna, because it has two rainy seasons--the intense summer monsoons and, in normal years, more sedate winter showers. The two rainy periods mean that as some perennial plants begin to die off, others begin to sprout. Still, average annual rainfall on the gunnery range is a paltry five inches.
Fecal analyses show the pronghorn's favorite foods to be weeds, grasses and chain fruit cholla, which has a moisture content of about 80 percent. Cholla fruit is believed to provide much of the pronghorn's water needs. In lean times, they also browse on ocotillo leaves and shrubs.
Until Hervert photographed Sonoran pronghorn drinking from the bomb crater, some students of the species believed it would not even drink from freestanding water sources. Some considered a total reliance on plants for water to be the Sonoran pronghorn's defining characteristic.
"Some people believe that if a pronghorn drinks, it's no longer a Sonoran pronghorn," Hervert says with a chuckle. He agrees that Sonoran pronghorn do eschew many water sources, but he believes it is because those sources are in canyons or areas that pronghorn avoid during the driest months.
The bulk of the U.S. population of Sonoran pronghorn prefer the eastern half of the gunnery range--the Growler Valley, Cabeza Prieta and Organ Pipe Cactus National Monument--although they do wander to the west and north during the winter, or when plentiful rainfall improves forage. Two radio-collared does were found to have ranges exceeding 1,000 square miles in the course of a single year.
Sonoran pronghorn have keen eyesight--one researcher estimates it is seven times more powerful than humans'--so they like open spaces, valleys and bajadas, the gentle inclines running up to the 17 mountain ranges arrayed across their habitat. Open space allows them to see their enemies--coyotes, bobcats, mountain lions--from a great distance, and flee.
During the fall breeding season, dominant bucks gather harems of does, mark territory and defend it against interlopers. Last week, during a telemetry flight, Hervert for the first time saw two bucks butting heads over rutting rights.
Other pronghorn species drop their fawns in midsummer. But in an apparent evolutionary tweak timed to take advantage of the lushest forage, Sonoran pronghorn fawns are born in March or April, often in pairs. Within a week, a fawn is fast enough to outrun a human.
"Pronghorn are built for one thing--to run fast," Hervert says.
Even so, he says, his investigations at pronghorn kill sites lead him to believe that the resourceful coyotes, working as a team, are capable of wearing down an antelope by running it in circles. "I've backtracked from a carcass and seen exactly how the chase played out," he says.
The Sonoran pronghorn is the smallest of the American antelopes. Bucks, which have barbed horns, weigh up to 125 pounds, and females about 75. It is said to be much lighter in color than its cousins, probably to better reflect sunlight and blend in with light soils. Its skull and teeth differ, too.
But there is some debate over whether the Sonoran pronghorn actually deserves its own subspecies designation. Only 14 specimens have been collected for study, and some taxonomists believe they show too few distinct characteristics to be considered a unique subspecies. Genetic comparisons have shown only slight variations between the Antilocapra americana sonoriensis and its more plentiful neighbor to the east, Antilocapra americana mexicana. Even if the two subspecies are someday determined to be one, the Sonoran pronghorn still could qualify as endangered under U.S. law, because it is an isolated population.
Bruce Eilerts, a biologist and chief of Luke's Natural/Cultural Resources Section, believes more study must be done to settle the question.
"Is it really a subspecies?" he asks. "Because if it's not, we don't have a problem."
John Hervert is convinced the Sonoran pronghorn is a distinct subspecies.
"There are traits that I can see visually; they look different to me, and there are behavioral things that support that idea as well," he says. "Comparing it to mexicana or americana, it's not quite a different species but it's not quite the same."
Hervert trusts his sense of the desert. He moved to Tucson when he was 3 years old, and has lived in Arizona since. His father was an avid outdoorsman, and as a youngster Hervert recalls encountering game wardens and marveling at the prospect that someone could make a living roaming the back country.
He took bachelor's and master's degrees in wildlife ecology from the University of Arizona and spent several years studying the effects of the Central Arizona Project canals on desert bighorn sheep and muledeer.
He went to work for the Department of Game and Fish in 1979 as a wildlife manager, was promoted to regional game manager and, finally, to wildlife program manager. He lives in Yuma.
Hervert may harbor a greater sense of urgency about Sonoran pronghorn than other scientists because he has actually witnessed isolated extinctions of species in the desert. He was part of a team studying desert bighorns in the Bighorn and Belmont mountains--and watched as their numbers dwindled to nothing.
"That was a learning experience to me to actually see what a vulnerable population looks like," he says, noting that bighorns can still be found in other mountain ranges.
"It made me realize just how vulnerable small populations can be. A lot of people I've worked with don't have as much experience in the desert. . . . It may be that they don't believe extinction is as likely as it really is.
"The thing about endangered species is once they're gone, they're gone. So you want to emphasize the highest level of management. Sonoran pronghorn have shown unique adaptions to the desert, and for that reason they're of some value to keep around and learn from."
Ever since a cluster of Sonoran pronghorn were found at High Explosive Hill, the gray hillock in the middle of the northern Growler Valley has become something of a mecca for far-flung biologists.
As soon as she realized what was happening, Cabeza Prieta ecologist Laura Thompson-Olais says, she began pestering biologists at Luke to do something. "I called and urged the people at Luke to actually assess the situation themselves," she recalls.
Notes from the August 29, 1995, multi-agency meeting of a committee known as the Sonoran Pronghorn Core Working Group provide the first written record of a problem at H.E. Hill: "Pronghorn were documented using water at HE (high explosive) hill 1-2 times/day during daylight hours. Approximately 15 different individuals were observed using this water . . . Pronghorn adults were documented chasing coyotes away from the waterhole."
Depending on who's estimating, 15 Sonoran pronghorn could account for up to 20 percent of the entire U.S. population.
The first evidence of what would be a grudging Air Force response to the problem is contained in U.S. Fish and Wildlife Service documents, which indicate that someone from Luke's environmental office called Fish and Wildlife's Ecological Services Field Office in Phoenix on November 9, 1995, "regarding ongoing activity that may be affecting Sonoran pronghorn."
Thompson-Olais convened an emergency meeting at Luke on December 4, "because I was frustrated by the lack of action by everybody," she says, including her own agency, the Fish and Wildlife Service. (Her frustration persists.)
The Air Force's summary of the December 4 meeting indicates that filling or fencing the crater was discussed. Someone suggested that the Air Force consider establishing a new H.E. Hill site. Luke officials said that wouldn't be possible. Gary Blake, Luke's air space manager, suggested that the potential for harm to pronghorn is probably greater from strafing runs at other sites than from bomb drops at H.E. Hill.
The summary also notes that the first bombing mission at H.E. Hill each day "includes a 'dry' fly-by to ensure that no personnel are on the ground in the target areas. This may have the effect of alerting the pronghorn and causing them to move from the area."
On December 6, Captain M.S. Monroe, chief of Environmental Flight at Luke, wrote to Fish and Wildlife's Ecological Services supervisor in Phoenix, Sam Spiller, saying the Air Force intended to pursue "informal consultation" with the wildlife agency regarding pronghorn at H.E. Hill.
Spiller, whose office is responsible for ensuring that the Endangered Species Act is obeyed, responded on December 8. He provided a chronology of communications between Luke and his office, including the November phone call, during which, Spiller wrote, "We recommended two courses of action at the time. The first was that . . . an evaluation of all activities in the area, their actual effects on Sonoran pronghorn, and a resulting determination of effect should be made. The second was that if Sonoran pronghorn are currently being affected (e.g., if pronghorn were in actual danger of being disturbed) by ongoing activities, then something should be done immediately to eliminate those effects."
Spiller wrote that these recommendations were reiterated during the December 4 meeting at Luke.
Two months later, the Air Force apparently had done nothing to implement Spiller's suggestions.
The Core Working Group includes representatives of the Arizona Department of Game and Fish, U.S. Fish and Wildlife, Cabeza Prieta, Organ Pipe, Luke Air Force Base and the Yuma Marine Air Station. At the group's February 22 meeting, the pronghorns near H.E. Hill sparked lively discussion. The meeting notes indicate that Cabeza Prieta biologist Steve Henry asked Luke biologist Bob Barry, "If PH [pronghorns] are detected in the area, can an operation be aborted?"
Barry: "Big bucks are involved if a mission is scrubbed. It is difficult to scrub a mission when we don't know the risk to PH."
Henry: "If the area is closed, it might not be for a day. The site might need to be closed for weeks or months."
Barry: "Their [Air Force] people would not like doing that; no evidence that any animal has been killed."
Bill Austin, a biologist from the Fish and Wildlife Service, piped up, telling Barry: "You need to know the effects; you may be killing PH; you need to determine the risks."
Austin later told Barry: "ES [Ecological Services] sent a letter to Luke AFB in early December looking for specific measures to protect PH in the ranges. There has not been a response. Activity possibly killing PH. Luke should very well be very nervous and try to do whatever they can do something."
On March 4, after two months' hiatus for cleanup, the Air Force began a new season of bombing at H.E. Hill--despite the fact that during a March 3 monitoring flight three or four pronghorns were observed bedding down on H.E. Hill itself.
Air Force biologists say they were never told that the pronghorn were on H.E. Hill.
But Hervert says the Air Force had been told that pronghorn were near H.E. Hill and other live-fire sites in the weeks leading up to the resumption of bombing at H.E. Hill.
In any case, Fish and Wildlife's Spiller was not amused. He wrote to the Air Force again on March 12, demanding that it begin a "formal consultation" with the wildlife service to document what was happening and what should be done. He closed by saying, "If pronghorn are likely to be taken, (FWS) recommends that appropriate action must be taken immediately to prevent it. One course of action that may prevent the take of Sonoran pronghorn would be to cease using the area as a live-fire site."
The Air Force has never given any indication it will make permanent changes in its training schedule or live-fire sites to accommodate the pronghorn.
But Spiller's letter apparently convinced Luke officials they had to do something. In a March 14 letter to Spiller, Captain M.S. Monroe, chief of Environmental Flight, agreed that "the increase of food and water in the vicinity of a live-fire training area does raise concerns regarding the safety of the Sonoran Pronghorn." She agreed that the consultation process should "continue in earnest."
A group known as Defenders of Wildlife thought the process should continue in earnest, too--in federal court.
As with many things governmental, preservation of endangered species is an exercise in semantical gymnastics.
The watchword of the Endangered Species Act is "take," which is defined to include "harass, harm, pursue, hunt, shoot, wound, kill, trap, capture or collect" an endangered species. Nobody can legally "take" an endangered species without the Fish and Wildlife Service's permission.
All federal agencies, including the military branches, are required to consult with the Fish and Wildlife Service to make certain their actions will not jeopardize an endangered species, a process that requires a "biological assessment" by the agency. The service then decides whether the information is sufficient and if "formal consultation" is warranted. If it is, and if the service concludes that jeopardy is likely, it must give the agency alternatives to remedy the violation. These alternatives can even allow for "incidental take" of a certain number of the species.
But during formal consultation, the agency is not supposed to engage in the activities then under review.
Defenders of Wildlife, a Washington, D.C.-based nonprofit group that claims 4,000 members in Arizona, believes the Air Force is unlawfully "taking" Sonoran pronghorn at H.E. Hill. After months of hectoring the Air Force, Defenders on May 22 sent Luke officials a letter of intent to sue.
"The ultimate agenda of any conservation group like Defenders of Wildlife is not just to cause problems for the military," says Greg Sater, former counsel to Defenders. "Our goal is to find some way to balance military training with wildlife.
"We're not talking about some snail or two-inch fish here. We're talking about a key component of the Sonoran ecosystem. This is a big, beautiful, charismatic, fast animal that evolved in the Sonoran Desert."
With the Fish and Wildlife Service and Defenders of Wildlife breathing down their necks, Luke officials on June 5 began sending a biologist to H.E. Hill each morning that bombings are scheduled there. The biologist surveys the area with binoculars, then gives the all-clear for the mission to begin. So far, one mission has been scrubbed because a pronghorn was sighted.
Defenders and others doubt the reliability of such surveys.
"It's pretty hard to see pronghorns down there," says Christine Maher, a pronghorn expert from Montana State University who visited H.E. Hill this summer. "The creosote bush is pretty tall. It could be hard to find them. They blend in well."
John Hervert concurs, saying, "Pronghorn are small animals and they blend in with vegetation and soils. Sometimes I can't see them when I have a radio receiver in my hand, and I know they're there."
In addition to visual sweeps, Air Force officials hired the Phoenix consulting firm of Geraghty & Miller to prepare the "biological assessment" required by law.
It was completed on August 30, and, among other things, it says that Sonoran pronghorn are probably habituated, and thus not disturbed, by jet overflights. This contradicts the Air Force's December 4, 1995, assertion that "dry" fly-bys were chasing pronghorns away before bombing began. And as recently as October 28, the Arizona Republic reported that "Luke officials" had said that "before they drop any bombs, pilots do a flyover to scare any animals away."
The Air Force's environmental assessment concludes: "The greatest potential impact to Sonoran Pronghorn resulting from military activities . . . appears to be death or injury to antelope on high explosive hills. . . . because no evidence suggests that military activities have caused a decline in the Sonoran pronghorn population or any deaths or injuries since 1941, measures to minimize or mitigate current or planned operations . . . do not appear warranted."
The wildlife service's Ecological Services office has until mid-January to review the Air Force's assessment and, if it decides "formal consultation" is called for, render a biological opinion. The service also could decide that it needs more information, or that the species is not jeopardized and nothing needs to be done.
Although he received the biological assessment on September 3, Bill Austin, the Fish and Wildlife Service biologist who will pass judgment on it, says he has not read it. The assessment has taken its place in a stack of other pending consultations.
Austin says, "I'm working on some other projects that are further behind, and I'm not sure when we might respond to that. . . . It's a matter of juggling things. The thing I'm working on I'm way behind on, like several months."
Defenders of Wildlife has challenged the Air Force's biological assessment, sending stacks of documents to Fish and Wildlife in the hope that Austin will rule that the Air Force's activities are placing this endangered species in legal "jeopardy."
Defenders' biologist Dennis Hosack, who also has made the pilgrimage from Washington, D.C., to H.E. Hill, told the wildlife service that the Air Force assessment "is deficient in several areas."
Maher, the expert from Montana, also has submitted comments challenging the document. She says the Air Force is "taking" pronghorn by harming and harassing them and upsetting reproduction, among other things.
"I strongly urge the FWS to conclude the Air Force's activities are extremely detrimental to the long-term survival of pronghorns, to do whatever it can to compel the Air Force to immediately cease all activities . . . that may threaten pronghorns, and to implement scientifically sound pronghorn management practices . . ."
Aiming for an injunction to get the Air Force to stop bombing H.E. Hill, Defenders wants to take sworn testimony from John Hervert, the state Game and Fish biologist whom it considers to be the authority on the current condition of the Sonoran pronghorn.
Incredibly, Justice Department lawyers initially filed a brief opposing Defenders' motion to depose Hervert. But last week, objections to the deposition were withdrawn. A lawyer for Defenders who was puzzled by the Air Force's opposition says he is equally mystified by its change of heart.
In any case, Hervert may be deposed within a week.
Asked to assess the Air Force's biological opinion, Hervert responds, "I don't think it was complete or all-inclusive."
What would he tell the court about the Air Force's overall response to pronghorn at H.E. Hill?
"I believe the Air Force needs to more aggressively search for alternatives to comply with the law, that's just my personal opinion."
He also might hand over his photos and videotape of Sonoran pronghorn, walking among unexploded bombs.
Luke Air Force Base employs three biologists, all of whom are convinced that more than enough is being done to keep the Sonoran pronghorn out of harm's way.
"The community thinks we're the evil empire because we work for the Air Force," grouses Bruce Eilerts, the affable chief of Luke's Natural/Cultural Resources Section. "People don't seem to realize that our true intentions are to help preserve the resources."
To support his claim, he notes his own credentials as the former head of the notoriously litigious Hawaii Audubon Society, and the Air Force's efforts in studying Sonoran pronghorn, including financial support for telemetry studies of its range.
Luke's biologists recently decided to begin their own monitoring of collared pronghorn, Eilerts says, but when they asked for radio frequencies of those collars, the Fish and Wildlife Service refused to give them up. The Air Force was forced to ask the service for a permit to track the collared animals.
It's a symptom of what Eilerts calls "bureaucratic little games . . . there's a lot of politics involved in this."
"Why are agencies that are supposed to be stewards of natural resources so resistant to share information?" he asks.
As he guides a tour to H.E. Hill for a reporter and a photographer (as well as a flight instructor, a second biologist and a public affairs officer), Eilerts adds, "I'm all for doing the right thing, but I don't like wasting time and resources barking up the wrong tree."
Eilerts says land inside the gunnery range is rich in wildlife and archaeological resources--including Native American camp sites and petroglyphs--and the land's best hope for remaining pristine is the military's oversight.
Recreationists are allowed on the range, with a permit, but Eilerts says the military keeps most areas off-limits to off-road vehicles and their sometimes rowdy owners.
"We help keep it Billy Bob-free," Eilerts says.
Eilerts says he has asked Luke officials about the possibility of finding new live-fire sites, but, "We are maxed out as far as where we can train. You need a lot of airspace to turn and maneuver."
Gary Blake, Luke's airspace manager, says that stopping live-fire exercises in pronghorn habitat is out of the question.
"Frankly, we've looked at everything we could, and I don't know of any other alternative which wouldn't impact our mission," Blake says. "There's no question in my mind that it would adversely affect training, and we don't have the luxury of having more pilots than we need right now."
John Hervert understands that the Air Force is on the pronghorns of a dilemma. But he says the people in charge of the Yuma Marine Air Station, whose pilots fly almost exclusively over the western half of the gunnery range, seem more eager to help. They have altered training schedules to avoid areas where pronghorn are known to gather at certain times of the year.
All in all, Hervert says, "If I was calling the shots, there would definitely be more active management of Sonoran pronghorn in spite of wilderness designations. We would be looking at reducing those factors that have a negative impact on Sonoran pronghorn."
Decrypted, that comment could spell more confusion and controversy among the web of agencies and interest groups transfixed on this small antelope.
Asked to elaborate on his preferred plan for saving the Sonoran pronghorn, John Hervert lists development of water sources, predator control and more capturing, collaring and radio monitoring of the animals--all actions certain to make some environmentalists gag on their trail mix.
Organizations such as Friends of Cabeza and the Wilderness Society can be counted on to oppose killing predators and creating water supplies for the Sonoran pronghorn. Hervert acknowledges that both measures are controversial.
In his 17-year career as an Arizona Department of Game and Fish biologist, Hervert has never advocated such extreme measures as predator control. Now he'd like to set up on the edge of pronghorn habitat, use varmint calls to lure coyotes, which are responsible for most pronghorn predation, then shoot them. He's writing an environmental assessment that would allow Fish and Wildlife managers to institute predator control on Cabeza Prieta during periods of winter drought. The public would be allowed to comment.
Pam Eaton, regional director of the Wilderness Society, says she finds it "interesting" that predator control is being considered. "I don't think there's a lot known about the distribution of predators in the range," she says.
Desert purists oppose water-source development because much of the pronghorn habitat is designated as wilderness and is not to be disturbed by man. The refrain about Sonoran pronghorn not needing freestanding water will be heard.
But many government biologists, including Luke's, also have reservations about artificial water sources. Bruce Eilerts calls them "fast-food stands for predators."
Eaton says the Wilderness Society opposed one proposal to create a water source for pronghorn because it would have been too intrusive, could have affected other species and was not scientifically sound.
"We've said we don't object to the idea per se, but we objected to this particular project as it was conceived," Eaton says.
There are manmade water sources sprinkled across the habitat, originally put there for cattle, but there's little reliable data on their usage by pronghorn--possibly because they are staked out by predators, or perhaps because the antelope are not in those areas during the driest months.
Another aerial count of pronghorn is set for next month, and if there are enough pronghorn to warrant more captures, Hervert wants to do that. However, he says he's been told that one conservation group may go to court to stop it.
Captures, in which individual antelope are caught in nets shot from helicopters, are indeed traumatic for the pronghorn. While in captivity, the animals are fitted with radio collars, and vital measurements and bacterial swabs are obtained. The chase and capture seldom last longer than 10 minutes--each minute crucial to an animal so frail that they have been known to succumb to capture stress.
Hervert concedes that a capture operation in 1994 was "disastrous"--due in part, he believes, to extreme drought stress the animals were enduring. Up to that point, he says, 160 Sonoran pronghorn had been captured in Arizona, and only one had died from capture stress.
But following the 1994 capture, six of 22 pronghorn collared were dead within two months. The radio collars have a mortality signal that begins pulsing once an antelope's pulse stops. Such a signal allows Hervert to find what's left of the pronghorn and try to figure out what happened.
Of those six mortalities, he attributes three directly to capture stress. Two others were killed by coyotes and one by a mountain lion.
Hervert participated in a subsequent capture in Sonora in which the pronghorn were given oxygen and intravenous fluids while they were studied. Those measures allowed biologists and veterinarians to hold the animals for up to 20 minutes and conduct more extensive tests. Yet the animals fared well, he says, and he hopes to use the same procedures--along with a five-minute chase limit--for any future captures in Arizona.
Since the 1994 captures, 11 of the 22 collared antelope have died from causes other than capture stress. Hervert fears that the entire population has declined at a quicker rate.
Estimates of fawn "recruitment" into the herd over the past 30 years have normally fluctuated between 30 and 50 fawns per 100 does.
During 1995, Hervert says, the ratio was 12 to 100.
This year, it's 0 to 100.
If conditions don't improve, wildlife managers may have to institute a captive breeding program.
One day last spring, John Hervert was observing a small group of pronghorn feeding on cholla. As the herd drifted off, he was startled by a pitiful sight: A day-old fawn staggered out of the thicket.
"It had the misfortune of being born in a cholla forest," he says. "Its head was completely covered with cholla. Its ears were stuck together on top of its head."
He watched as a doe spurned the fawn's efforts to nurse.
"I went down where this fawn had curled up--I had gloves on--and picked out all the needles I could."
He also found the fawn's twin, which was in similar straits, and removed the spines from its head.
Taking the fawns crossed his mind. What biologist wouldn't have considered it? Better to rescue and study them than let them become coyote snacks.
"I know those fawns died," Hervert says.
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