"YOU BOND TO THE TORTOISES YOU FIND." On the edge of Little Shipp Wash in west-central Arizona, the Sonoran Desert is settling in for the night. But the people inside a small trailer ignore the rattling call of a frog in a nearby acacia tree, the scent of moss and wet sand rising up from the arroyo, the twitching of the mesquites in the cool May breeze.
In the kitchen of the mobile home, veterinarian Mark Trueblood and biologist Vanessa Dickinson hover over a desert tortoise, which is balanced on an old coffee can atop a table. The eleven-pound, twenty-year-old male with the no-nonsense name of "Tortoise 500" has a little radio transmitter glued to the top of his hard gray shell. The air is ripe with the vinegary smell of the reptile and the stench of rubber gloves--and worry. Tortoise 500 is futilely kicking while the two humans treat a ragged, bloody gash in one of his scaly legs.
Earlier in the day, Tortoise 500 was accidentally stabbed with a snake hook during an Arizona Department of Game and Fish tortoise study in this isolated stretch of desert 100 miles northwest of Phoenix, just off the highway winding toward Kingman.
The last thing Dickinson needs is to have one of her staffers accidentally stab a desert tortoise while the team is doing trailblazing research on why tortoises in the Southwest are dying.
The guy who wounded Tortoise 500, John Patton, stands helplessly outside the trailer in his dusty Game and Fish uniform. Patton's job of fisheries assistant usually entails counting and studying fish in Arizona lakes. But he loves the desert and had persuaded his supervisor to lend him to Dickinson for a few days of tortoise work.
He didn't mean to stab Tortoise 500 with that snake hook, Patton has miserably said more than once. He had only tried to hook the tortoise's shell so he could pull it out of its rocky burrow deep within the ground. Like a child, Patton crosses his fingers as he waits.
Inside the trailer, Vanessa Dickinson, who is meticulous about her work, tries to hide her annoyance. The reptile was injured stupidly, needlessly. Earlier in the day, when Patton brought the tortoise in from the desert in a bloody pillowcase, Dickinson had controlled herself. "These things happen," she had said. And then she disappeared into the trailer and occupied herself with the routine task of converting the mobile-home kitchen into a science lab, preparing the centrifuge and the test tubes for the long night ahead.
For the most part, Dickinson says she admires her Game and Fish co-workers for what she calls "altruism"--they work long hours of overtime, without pay, because they are committed to helping creatures.
People like John Patton are part of a breed that is becoming as scarce as the desert tortoise--the Marlboro-man Arizonan who still opens doors for ladies and is more at home in the wild Sonoran Desert than on the streets of Phoenix.
"It is almost like Jack London," Dickinson says. "A hundred years ago, these men would have gone to Alaska in search of gold because they love nature. These men love the desert, and are touched by the fragility of it."
That's a partial explanation of why some of Arizona's desert tortoises are crawling around with little radio transmitters glued to their backs. Three times a year--spring, summer and fall--Dickinson and a crew of volunteers hike into five remote study areas of Arizona and southwestern Utah to gather and examine dozens of these tortoises.
Dickinson's five-year study, formally called the "Health Assessment of Desert Tortoises in Arizona and Utah," is aimed at trying to find out why some groups of desert tortoises are dying at alarming rates. It's part of a flurry of federal and state studies into the health and welfare of desert tortoises in the Southwest. (Tortoises are not to be confused with turtles. The main difference is that tortoises, unlike turtles, cannot swim.)
There are two rapidly perishing species of Southwestern tortoises, named after the deserts where they live--the Mojave and Sonoran. The Sonoran tortoises live near Little Shipp Wash and elsewhere in Arizona and northern Mexico.
The Mojave tortoises, which live mostly in the vast, partly urbanized desert east of Los Angeles, are in greater danger of extinction. Dickinson's study overlaps into both species--some Mojave tortoises live in the Arizona Strip, north of the Grand Canyon.
It turns out that Dickinson spends much of her time studying healthy tortoises. One method of unraveling the mystery of dying tortoises is for scientists to find out everything they can about exactly what makes a healthy tortoise. For now, scientists aren't sure.
"I FOUND 500," says Vanessa Dickinson. "You bond to the tortoises you find." She makes his number sound like a nickname, but that's not surprising. Tortoise 500 happens to be one of her very favorites. And Dickinson has had many to choose from; she has spent the past year immersed in tortoises. Thirty years old, with a master's degree in biology, Dickinson has conducted such complex and important projects as health studies of timberwolves in the Midwest. Dickinson earns $25,000 a year from Game and Fish--she could make more working as an environmental biologist for, say, an oil company.
Altruism is a big virtue in her book--she's proud of having taught university-level science classes in the Philippines during a Peace Corps stint in the mid-Eighties.
Being outdoors is another--there are unhealthier professions than hers. Bounding after tortoises keeps Dickinson slim and fit, although as a blonde from Minnesota, she has to douse herself with sunscreen to keep her skin from looking like a tortoise's.
She first saw Tortoise 500 during a hike in late April. After climbing several granite ridges about a mile from her campsite, Dickinson reached the kind of dark, rocky shelters that tortoises love. Like a dentist searching for cavities, she used a mirror to reflect sunlight into the rocks. And there he was.
Reaching into her backpack for a tiny radio transmitter, she glued it to the tortoise's shell with epoxy. Tortoise 500 became the eighth in the area to receive a transmitter.
A week later, Dickinson and her team used radio receivers to track down 500 and the other tortoises. (Each animal's transmitter broadcasts on a different frequency.) The tortoises were captured and taken back to camp, where they were weighed, measured, sedated and probed. The temperature of each tortoise's shelter and other details of its world were duly noted.
The tortoises spent the night in cardboard boxes in the trailer--while the scientists slept outside. The next day, each tortoise was released exactly where it was found the day before.
The tortoises, of course, don't seem to enjoy all this poking and prodding. But Dickinson treats them rather as a parent treats children who don't want to eat their spinach: "You may not like this, but it's good for you."
IN THE 1950s, an Arizona Strip gas-station owner named Beaver Dam Bill would pay sheepherders to collect baby tortoises from their burrows. He kept them in a pen behind the gas station and sold them to tourists for $1 apiece. Beaver Dam Bill also gave away tortoises to customers who purchased full tanks of gas.
In the late 1980s, dozens of bullet-ridden desert tortoise shells were found at a California shooting range. The reptiles had been used for target practice.
At about the same time, a California man was arrested for purposely running over tortoises on highways in the Mojave Desert. He told the cops he enjoyed the popping sound of a tortoise beneath his wheels.
Desert tortoises have suffered a variety of humiliations.
In northern Mexico, tortoises are prized by gourmets. But in other parts of Sonora, they are clowns. Live tortoises are captured and decorated with gaudy fringes and baubles that make them look like Mexican taxicabs. Just for fun.
Timothy Duck, a federal wildlife biologist in Utah who works with Dickinson, knows all such horror stories about man's inhumanity to tortoises. Among the killers linked to tortoises' contact with humans are disease, an increase in predators, the dwindling of desert plants, urbanization.
But there are other factors, too. And scientists believe that Mojave tortoises are in more danger of extinction because they live in the desert flatlands, where they are more susceptible to man and disease. Sonoran tortoises love the rocky highlands, which are less accessible to both.
Researchers don't have a lot of numbers about the population decline among tortoises, because the animals haven't been extensively studied. What scientists do know is that some small groups of tortoises that are currently being studied are dying out rapidly. For instance, in southwestern Utah, one group of Mojave tortoises has dwindled by 25 to 50 percent during the past ten years, Duck estimates. And in 1990, in the Maricopa Mountains southwest of Phoenix, Game and Fish researchers noted a high death rate among Sonoran tortoises. Of seventy tortoises previously known, only seventeen were alive.
In the Maricopa Mountains, drought is thought to be the culprit. No rain means fewer desert plants for these vegetarian reptiles. They simply starve.
But in some parts of the desert where there is water, tortoises are dying anyway. Scientists suspect a mystery disease called Upper Respiratory Tract Disease.
The working theory is that pet tortoises, which naturally burrow into the ground as deep as ten feet to hibernate, are victimized by the moist earth of their owners' backyards. (It's against Arizona law to take tortoises from the desert, but it happens. It's not illegal to buy one from a pet shop.) Sometimes too much moisture causes either a bacterial or viral infection--scientists aren't sure which. When humans tire of their tortoise pets, they release them back to the desert, where the tortoises infect their undomesticated cousins. It doesn't help that tortoises enjoy sniffing other tortoises' noses. That makes diseases easily spread.
The situation exasperates biologists like Duck, who says, "We ask people not to take tortoises from the desert, and then we ask people not to put them back."
Humans make other mistakes. Well-meaning desert trekkers pick up wild tortoises out of curiosity. Frightened, the animals often urinate. This can kill them during dry years, says Dickinson, because tortoises store water in their bladders. They die of dehydration. (To prevent dehydration, each tortoise studied by Game and Fish is injected with a solution of sugar, salt and electrolytes before it is released into the wild.) Tortoises always have faced a major threat from their natural predator, the raven. Unfortunately for tortoises, the raven population keeps growing--in part, thanks to humans. The big black birds scavenge landfills and feast on roadkill.
Humans are also linked to other problems for tortoises. Ranchers' cattle and sheep overgraze the desert, leaving little food for tortoises. European grasses introduced by ranchers as good cattle feed are bad for the tortoises.
The European grasses overtake native shrubs that are among tortoises' favorite foods. After desert wildfires, the imports thrive and regenerate; the native shrubs usually don't.
People in off-road vehicles ravage tortoise habitat, killing many young ones in their nests. They do so much damage to tortoise habitat that last year in the Mojave Desert, the U.S. Bureau of Land Management chose tortoises over people. In a controversial move, the feds canceled the 23-year-old Barstow-to-Vegas motorcycle race, which had attracted about 1,200 entrants each year.
TORTOISES HAVEN'T always been victims. According to Pima legend, the desert tortoise, called comkichitt, played a major role in the creation of the world.
Only a handful of people on the Salt River Pima-Maricopa Indian Community east of Scottsdale still remember the legend. Dorothy Lewis, an elderly member of the group, has passed it on to a younger Pima named Margo Menson, who tells it this way:
When the world began, Tortoise was entrusted with the seeds for humans' crops. Taking this responsibility seriously, Tortoise hid the seeds beneath his body.
Coyote tried to get the seeds away from Tortoise. He tried to overturn Tortoise, but Tortoise was too heavy. He tried to claw Tortoise's shell, but it was too hard. So Coyote started a long conversation with Tortoise, and eventually Tortoise became so intrigued with Coyote's talk that he forgot about the seeds and crawled off them.
Coyote grabbed the seeds and spread them unevenly throughout the Earth. This is why today some parts of the world are barren and others are lush.
The Pima were once fascinated by the tortoise. Old-timers say their forebears swore that tortoises had special medicinal powers, but they can't recall the specifics. A few Pima seniors remember that hunters believed the sighting of a tortoise meant that plentiful game was nearby. But now even the folklore about tortoises is nearing extinction. Some oldsters were taught children's songs about the friendly animal, but now they can't remember the words.
MODERN-DAY SCIENTISTS are just as intrigued by the tortoise as the ancient Pimas. But the way they show their respect is slightly different.
Vanessa Dickinson, for example, enjoys staring at tortoises for hours, taking notes about everything the tortoises put in their mouths.
By doing these "bite counts," Dickinson and other biologists have learned that the tortoises' favorite food, among many other high-protein desert plants, seems to be the prickly pear cactus.
In the spring, they chow down on the cactus's bright pink or yellow blooms. But autumn is the best time to eat prickly pear. That's when the beet-red fruit falls to the ground, providing a ready-made feast for tortoises. Often, they eat so much prickly pear fruit that their lips are stained a bright red.
"They are very cute," says Dickinson, who often is armed with a Nikon. She once won a photograph contest, sponsored by tortoise scientists, for her portrait of a pink-lipped glutton known as Tortoise 303. "I saw 303 and he saw me and we both stopped and I took his picture," recalls Dickinson. "I won $25."
Is it tedious to conduct six-hour bite counts of tortoises? John Snider, a Game and Fish researcher who is Dickinson's only full-time assistant, finds the stakeouts "fascinating."
Tortoises can be either scared or friendly around humans, but in either case they're usually docile. "They're not tame, of course, but they seem to be tame," says Snider, who is always amazed when tortoises aren't bothered by the close presence of humans. Yet the animals can be vicious with one another. Larger ones sometimes pick on smaller ones for no apparent reason, flipping their victims over on their backs. When the weaker tortoises manage to right themselves, the bullies often flip them over again.
Mark Trueblood, the Glendale veterinarian who often treats pet tortoises in his private practice, swears that tortoises have different personalities. Some are curious enough to follow humans and rest in their shadows. Others are more likely to simply withdraw into their shells. Finding that personality can be difficult, no matter how much time you spend with them. "I have been waiting to nickname four of them `Michaelangelo,' `Donatello,' `Leonardo,' and `Raphael,'" says Dickinson, referring to the Teenage Mutant Ninja Turtles' monikers. "But I haven't found the right personalities yet."
Tortoises see color, insists Trueblood, pointing out that tortoises are attracted to a woman's painted red fingernails.
Desert tortoises can live 100 years; their ages are calculated by counting the rings on their shells--like rings on a tree. They reach sexual maturity between the ages of eight and thirteen years old, and from then on a female tortoise might lay eggs a couple of times a year. But that's where motherhood stops.
Life is tough right from the start. Females abandon the eggs after laying them, and the hatchlings, about the size of silver dollars, must make their own way in the world of ravens and off-road vehicles.
THE SCIENTISTS' tortoise roundup in early May started off without a hitch.
Dickinson had camped out on the bank of Little Shipp Wash with her team--assistant John Snider and two volunteers, Julie Strater from California and Judy Raynack from Washington.
Strater met Dickinson through a California foundation that finds rich patrons for poor scientists. After they hooked up a few years ago, Strater helped fund Dickinson's research on a Texas bird called the crusted caracara. The two have been friends ever since.
Strater's friend Raynack is a middle-aged mom who has done a number of different things in her life. Right now, she has a catering business and is a personal assistant to an opera singer. "God, I should have gotten into what Vanessa does," Raynack says. "That's a career I would have loved."
By 7:30 in the morning, Game and Fish staffers John Patton and Craig Heath arrive in their trucks. Dickinson passes out topographical maps of the study area where the tortoises had last been sighted. She distributes routine tortoise roundup equipment: Snake hooks for coaxing tortoises out of burrows, pillowcases for transport, colored plastic ribbons to mark locations, and gloves to prevent the spread of disease to the tortoises. Then Dickinson splits the group into three crews. Each crew has a radio receiver.
After navigating a big four-wheel-drive Chevy pickup to the base of the study site, Dickinson and Raynack head into the hills.
The rains have made a garden out of this bit of high desert. Groves of fire-red ocotillos cluster on the hills, and thousands of orange butterflies flutter around mustard-yellow paloverde trees. The rocky terrain explodes with potential tortoise food--fuchsia prickly pear cactus blooms, yellow flowers and pink-white buckwheat bushes.
Armed with a radio antenna, Dickinson looks like a Martian in her Game and Fish uniform, dark glasses and wide-brimmed hat. Holding the antenna high in the air and consulting her topo map, she tunes the receiver to the specific frequency of Tortoise 302's transmitter and soon picks up a faint "beep beep beep." Rotating the antenna as she walks, Dickinson locates Tortoise 302 in less than ten minutes.
He's sunning himself in front of his burrow, high above a creek called Cottonwood Wash, surrounded by prickly pear.
Tortoise 302 is an old guy, perhaps sixty, with signs of osteoporosis on his shell. Instead of withdrawing into his shell, he looks at his human visitors. This isn't the first time he's been captured by Game and Fish.
"Oh God," gushes Raynack. "Oh baby, oh baby. Oh, he's so cute. God, I just want to kiss him."
But Raynack restrains herself, dons a pair of surgical gloves and gently lowers him into a clean white pillowcase. Dickinson marks the location on the topo map and tags a bright orange flag on a paloverde to mark the spot where Tortoise 302 would be returned the next day.
Dickinson tells Raynack to hang back with Tortoise 302, so the reptile's radio transmitter won't interfere with Dickinson's quest for Tortoise 303. She figures Tortoise 303 must be close, since last year he roomed with Tortoise 302 in a nearby shelter. She's right. Within minutes she finds 303.
Then it's off to find Tortoise 500. He is about a quarter of a mile away, practically underground, hiding deep within a crevice. Dickinson can't reach him and decides to send other staffers after the tortoise later in the day. Perhaps then he'll be out sunning himself.
Walking gingerly so as not to upset Tortoises 302 and 303 in their pillowcases, Dickinson's team heads back to the truck, where they rendezvous with the rest of the crew.
The news is good; the seven tortoises who had been fitted with radios last year have been found and are thriving. They are removed from their pillowcases, placed in clean cardboard boxes and chauffeured back to camp at Little Shipp Wash. The entire roundup takes less than two hours.
At the camp, Raynack and Strater help weigh and measure the tortoises and stuff the animals' cigarlike scat into test tubes.
In the meantime, Patton and Heath go out after Tortoise 500. About an hour later they return, but this time the news is bad. Patton explains how he accidentally wounded 500 with the snake hook.
Dickinson will later blame herself for not instructing the men to capture him if he had been outside his shelter. "I assume too much sometimes," she would later say. "I assumed they'd leave him there if he wouldn't come out."
Tortoise 500 is lucky. The crew is worried, not even sure whether the bleeding tortoise will survive. But veterinarian Mark Trueblood already is on his way to the camp for routine sedations and blood-sampling of the tortoises.
When Trueblood arrives at sunset, he immediately sets to work on Tortoise 500. The prognosis is favorable. With Dickinson's help, Trueblood sprays the leg with medicine, wraps white gauze around the ripped flesh so it will soften enough to be stitched up the next day.
"Gonna be okay," says Trueblood, who looks out of place in his city-slicker boat shoes and blue Polo shirt. He places the tortoise in a brown cardboard box beneath the mesquites, near the seven other boxed tortoises.
Patton says nothing, but he clearly is relieved. The crew starts to work on the seven other tortoises, first by sedating them. Later in the evening, they will be bled, poked and prodded. The next day, they will be released into the desert.
Tortoise 500 is spared the ordeal. He'll be taken to Trueblood's clinic in Glendale for further treatment and recuperation.
AFTER A WEEK in Glendale, it's time for Tortoise 500 to go home.
Vanessa Dickinson arrives at Apollo Animal Hospital with a nice, clean cardboard box. She is delighted to hear that Tortoise 500 has been eating a great deal of broccoli, although he prefers the grass in his little pen. He is still wary of human beings, however, and when he sees Dickinson, he tucks his head into his shell.
Riding in the box in the back of the Chevy pickup is supposed to make a tortoise feel secure. "That's a hypothesis, of course, because we can't talk to tortoises," says Dickinson. "But we don't want them to slide all over the back of the truck. And we don't want to stress them because we don't want them to lose their water."
Tortoise 500 hides in his shell the entire trip to Little Shipp Wash.
But when Dickinson parks the Chevy in the desert and lifts him out of the box, he comes out of his shell.
The wind carries the sweetish scent of a purple flowering bush, one of Tortoise 500's favorite foods. Every living thing in sight seems content. A huge turkey vulture rides a thermal in the incredibly bright sky. Tortoise 500 is home.
Dickinson gently tucks Tortoise 500 into a pillowcase and hikes about a mile up to the ridge above Cottonwood Wash. She is annoyed that Patton and Heath had apparently failed to flag the animal's shelter with a bright plastic ribbon. "Sometimes my volunteers don't read my instruction sheet," she says.
After studying her map, she can't find the exact spot of Tortoise 500's burrow. But she knows it's nearby and so she sets him in a rocky shelter. He'll crawl to his own home once the humans leave, she says.
Dickinson plucks a bright pink flower from a prickly pear and places it in front of Tortoise 500. Although the wind is blowing fiercely, the shelter is protected, and the petals barely flutter. "If you're thirsty, this will be good," she tells Tortoise 500.
The tortoise cranes his neck, sniffing the air for perhaps a minute or so. He yawns, the inside of his mouth surprisingly large and white, and Dickinson laughs. Tortoise 500 stares at her. He yawns again. She laughs again. Tortoise 500 rests his head on the prickly pear petals and falls asleep.
Why are Arizona's desert tortoises crawling around with radio transmitters glued to their backs?
Like a dentist searching for cavities, she used a mirror to reflect sunlight into the rocks. And there he was.
The tortoises spent the night in cardboard boxes in the trailer--while the scientists slept outside.
"We ask people not to take tortoises from the desert, and then we ask people not to put them back."
Last year in the Mojave Desert, the U.S. Bureau of Land Management chose tortoises over people.
When the world began, so the legend goes, Tortoise was entrusted with the seeds for humans' crops.
Tortoises often eat so much prickly pear fruit that their lips are stained a bright red.
"Oh God," gushes Raynack. "Oh baby, oh baby. Oh, he's so cute. God, I just want to kiss him."
After a week in Glendale, it's time for Tortoise 500 to go home.
