Life Everlasting

by Bernd Heinrich

  The giraffe I observed had lived in the acacia bush in South Africa’s Kruger National Park. It had probably been down only one day when I found it lying within a hundred meters of a sandy road in semidesert acacia gallery forest. It was late morning, and some of the show was already over, so what I write here is largely extrapolation and speculation.

  I suspect that the giraffe was old or sick, because a healthy one is not normally taken down by lions, several of whom were nearby. These cats, weighing 250 to 300 pounds, can ingest 35 pounds each in a night of feasting. In the heat of the day, they were lying in the shade of an acacia tree.

  The lions had probably killed the giraffe in the night, and their commotion attracted hyenas and jackals. After satisfying their appetites, the lions yielded to the insistent harassment of the hyenas, who, when they in turn were sated, yielded to jackals.

  Soon after the morning sun had warmed the plain and the warm air had risen, vultures flew from their perches in some communal roosting place. They spiraled ever higher, their sharp eyes scouring the plain. The first vultures to see the carcass and the lions, hyenas, and jackals scattered about stopped soaring and started their gliding descent. Other birds in the distance, also soaring, watching not just ground but also sky, saw the first vultures begin their descent and did the same. And so on, one vulture informed by the next more distant one, until a horde of hundreds was barreling in from all directions, perhaps from over a hundred miles away. Some of the vultures were already done feeding when I arrived. They were perched in the nearby trees, and some were flapping off again.

  In a day or so not much would be left of the carcass. Any meat remaining would be flyblown, with writhing masses of maggots. After the large meat eaters leave, the remains are reduced to dry bones and hide and fur, and then beetles fly in, and they and their larvae finish up the scraps.

  Meanwhile, the lions, hyenas, and jackals process the giraffe’s remains into scat, and (as I will explore later) dung beetles process even that last remnant of the giraffe, including whatever it had eaten during its lifetime. The beetles fashion animal dung into round balls, which they roll for long distances and then bury, to serve as food for their offspring. After the next rains, when the earth softens and fresh green grass and flowers spring up anew, the young beetles emerge at night and fly off, skimming over the veldt, guided by the scent of antelope, elephant, rhino, hyena, or lion excrement, in search of further feasts. As they fly, many are caught and eaten by bats at night and by gorgeous birds (including fishers, drongos, starlings, and rollers) during the day. One giraffe died, but a dozen lions, hyenas, and jackals and perhaps hundreds of vultures were fed. Thousands of dung beetles had a feast, and the plains would grow more grass.

  WE KNOW LITTLE about animal undertaking in the natural ecosystem of North America in the Pleistocene. We have glimpses, though, and there is room for speculation. In 1953 the renowned ornithologists Roger Tory Peterson (an American) and James Fisher (British) got together to take a 30,000-mile journey to “Wild America” and write a book about it. In the prologue, Peterson wrote that they were both “completely devoted to the study of the natural world—the real world.” The highlight of their trek was seeing a single American condor in the distance in California. The condor, Peterson wrote,

  was like a bomber, its flat-winged posture quite unlike the glider-dihedral of the turkey vulture. It was huge, black, pale-headed, and as it came over, the big white bands forward of its under-wings showed it to be an adult. For five minutes we watched its monstrous ten-foot span, its primaries spread like fingers. It made a couple of flaps, as if it had all the time in the world, caught a new thermal, and soared away to the southeast until it became a tiny speck and disappeared.

  The sad part is that this disappearance, then as now, seemed literal. Peterson and Fisher were skeptical that the California condors could survive as a species, and they wondered whether putting out carcasses might help the remnant population, then estimated to be about sixty individuals in the whole world, survive. A “last-ditch effort” had already been made to save the birds by artificial propagation, following the example of Andean condors, which had been bred in captivity at the San Diego Zoo. Normally in the wild, under ideal conditions, condors raise only one chick every two years. But in the zoo it was possible to get four offspring from a captive pair over that same time by taking their first egg to hatch in an incubator. The female immediately lays a replacement egg, which she is allowed to keep and raise, but only until the chick is half-grown. It is then removed and hand-raised, at which time the female initiates a second breeding, yielding two more chicks by the same process of egg removal and hand-rearing.

  Peterson had suggested such a plan for the California condor, but it had unfortunately not worked out. Permits for the project had been obtained from the California Fish and Game Commission, but the attempt to capture a pair of birds for captive rearing had failed. When the permit expired, the project was abandoned. Fortunately, the “last-ditch effort” was again tried, though not without controversy, thirty-four years after Peterson suggested it.

  Not until fourteen years after Peterson and Fisher’s 1953 trip and their dire prognosis was the California condor placed on the federal endangered species list. Even then their numbers continued to spiral downward. Eventually only twenty-two individuals remained of the entire population, so in 1987 the controversial decision, by then truly a last-ditch effort, was made to capture all of these wild birds and bring them into captivity. This time the capture attempts were successful, and the last remaining wild bird was caught on April 19, 1987.

  The goal of the U.S. Fish & Wildlife California Condor Recovery Program was “at a minimum to establish two wild-breeding populations of at least fifteen pairs each from the captive-hatched released condors.” Male and female condors look the same; pairs mate for life, and the mates take turns incubating their one egg for fifty-six days. The young fledge after six months and may still be dependent for another half year. Some of the captive-bred individuals, which were released into the wild beginning in 1992, may still be alive, since these birds live up to sixty years, commensurate with their very slow reproductive rate.

  As might be expected in such a worthwhile, major, but risky undertaking, the captive-rearing program ran into difficulties. Five of the released birds soon died from lethal contacts with electric power lines. A program was then initiated to train the remaining captives to avoid power lines by administering small shocks if they landed on one, before releasing them into “the wild.”

  Currently there are three condor release sites, one in California, another in Arizona, and a third in Baja California. As of 2011, the world population of California condors totaled 369. Of these, 191 are in the wild (97 in California, 74 in Arizona, and 20 in Baja), and the rest are still captive. The world’s largest vultures, the Andean condor, Vultur gryphus, and the Eurasian bearded vulture, are designated “near threatened” by the International Union for Conservation of Nature.

  Prehistorically, the California condor lived in the West from Canada to Mexico and in the East from Florida to New York. Its bones and eggshells have been found in nesting caves in the Grand Canyon. But 10,000 years ago it experienced a dramatic reduction when man came on the scene and the mammoths, giant sloths, and saber-toothed cats went extinct. At that point the condor was probably restricted to the Pacific coast, where it apparently scavenged on the washed-up carcasses of large marine mammals, as the explorers Lewis and Clark witnessed. After the influx of Europeans, the birds suffered from habitat destruction, DDT, and lead poisoning. Sadly, “the wild” is no longer a suitable place for some vultures.

  Portraits of the North American vultures: black vulture (left); turkey vulture (top right); and California condor (bottom right). Note the flight silhouettes of the black and turkey vultures.

  WE ARE IN a human-generated wave of animal extinctions, and animal undertakers are especially hard hit by it. The greatest cause of population crashes, and possible extin
ctions, of some of our large undertaker animals, such as the great cats, hyenas, wolves, and vultures, is our decimation of the vast herds of ungulates, which provided their food base. In addition, we have traditionally granted the large undertakers little respect; killing the scavengers that feed on dead animals has been encouraged in part because they have often been blamed as the killers. As I have emphasized, the line between predator and scavenger is a thin one in some species. Both predators and scavengers are hated, especially by herdsmen whose livelihood depends on domesticated animals selected for their tameness and helplessness, who, like sick animals, are apt to become prey. Herdsmen tend to see an animal death not as a recycling into other life but, if perpetrated by an animal other than themselves, as a criminal taking of life and their livelihood. They see predators and scavengers as direct competitors and hence deserving of retaliation. Many predators are easily killed by being lured to a tethered live animal. And scavengers from long distances die from eating carcasses deliberately laced with poisons, which have killed many undertakers at one blow. Today, as I will indicate, even more potent poisons meant to kill crop-eating rodents kill other animals unintentionally as well.

  As I’ve stated, the most potent human intervention that affects the undertakers is our wholesale removal of large wild animals from the ecosystem and their replacement either with domestic herds for our consumption or with agriculture that removes habitat. But other factors contributing to the destruction of the large undertakers include our methods of animal husbandry, dangerous chemicals, methods of carcass and meat disposal, and cultural practices. Some of these are difficult to rectify, but others could be solved simply by overcoming cultural taboos. One of the most damaging practices affecting the undertakers’ livelihood may be our deliberate removal of carcasses that have, throughout evolutionary history, been left to return to the earth. Even parts of animals that used to be “waste” and that could have fed vultures are now processed into hot dogs and the like, although a small concession is made in saving suet for birds such as woodpeckers, nuthatches, and chickadees.

  Most parts of any domesticated livestock are now cycled only into human consumption, with scraps converted to pet food. Thus we and our pets are vulture stand-ins. But if an animal that is deemed not suitable as food for us dies, we also deem it unsuitable for availability to others. Even the road-killed deer and other animals that the highway department picks off the roads are disposed of by burying. Vultures would do the job better if we let them.

  SINCE THE DECLINE of the large undertakers has been so gradual, hardly anyone notices. A recent exception that brings the disturbing problem to attention is that of the white-rumped vulture, Gyps bengalensis. This species nested in trees in colonies near humans and used to be prominent in the morning skies (after the air warmed and the birds could soar) above cities in India. It fed on human remains and helped dispose of other animal carcasses. It was said that these common vultures, coming together in swarms, could dispose of a cow in twenty minutes. These “ecosystem services” were also city services, much like the services ravens performed in medieval European cities such as London.

  The white-rumped vulture declined in Southeast Asia over the twentieth century because, as a result of the collapse of wild ungulate populations, fewer carcasses were available. Yet it was still described as “possibly the most abundant large bird of prey of the world.” It had ranged through India, Pakistan, Nepal, Cambodia, Myanmar, Bhutan, Thailand, Laos, Vietnam, Afghanistan, Iran, China, Malaysia, and Bangladesh. Then, during the 1990s, the population experienced a sudden collapse to fewer than 10,000 individuals. The only extant viable populations now are in Myanmar and Cambodia, and this vulture is classed as “critically endangered.”

  The white-rumped vulture’s decline grabbed attention because this bird was common and well known before its very rapid collapse, which was traced to its feeding on livestock that had been treated with the anti-inflammatory drug diclofenac. In vultures the drug led to kidney failure. It does not require many cows to be treated with this medicine to have lethal effects on a vulture population. Modeling now suggests that the observed population declines can result if only one in 760 carcasses contains the drug. And of course nobody thought it necessary to test whether a drug made in America that makes cows well would make vultures in Iran or China or India sick.

  Although the most attention has been focused on this species because it was so common, the same drug, which is used worldwide, caused the same catastrophic decline in at least three other vulture species: the Indian vulture, Gyps indicus; the slender-billed vulture, Gyps tenuirostris; and the Asian king (or red-headed) vulture, Sarcogyps calvus.

  The European counterpart of the white-rumped vulture, the griffon vulture, Gyps fulvus, was once widely distributed over large parts of Europe. This species would undoubtedly have suffered the same collapse—if it were still around to collapse. It had disappeared from Germany by the eighteenth century, due to the unavailability of carcasses. Tiny, isolated colonies of griffon vultures exist now mainly due to reintroductions from captive breeding and “vulture restaurants,” where uncontaminated meat is deliberately left out for birds released after being raised in captivity.

  The griffon and three other vulture species used to be common in Israel, where they nested in colonies of hundreds. Recently the populations have experienced a precipitous decline from the use of thallium sulfate as a rodenticide.

  There is no letup in these assaults, with “newer-generation” rat poisons, such as Havoc, Talon, Ratimus, Maki, Contrac, and d-Con Mouse Prufe II, continuing to come into the market. They contain anticoagulant compounds, and the rodents who eat them either die outright or become weak and thus are easy prey for all sorts of animals. It takes months for the chemicals to be eliminated from the bodies of the predators/undertakers; these poisons have recently been detected in 70 percent of barn owls examined in western Canada, where they are “threatened”; in eastern Canada they are “endangered.” But this is only the barely visible tip of a large iceberg: rodents are a favorite snack for countless species all over the world.

  Biocides should be outlawed. Rodents can indeed multiply even faster than the proverbial rabbits, as I observed when I left grain for my unguarded chickens. But there are other methods of rodent control. I once easily captured a dozen rats in one night using a drop-in trap made from a trash can; I killed them with a stick. A slower but surer method would be to foster populations of native owls and kestrels. One major limiting factor for these birds is the lack of hollow trees to nest in, but putting up suitable nest boxes in proper locations would help them greatly where old trees are not available.

  The New World vulture populations have a mixed record of survival so far. The turkey vulture, Cathartes aura, and the black vulture, Coragyps atratus, are both doing well, and indeed both are greatly expanding their range northward as carcasses stay unfrozen farther north. The black vulture ranges from southern Argentina to Latin America but has recently expanded into the Gulf states and most of the Southwest, where it now roosts by the hundreds at night in towns and cities. The turkey vulture, once a strictly southern bird, now breeds even in Canada. For decades I never saw a turkey vulture, but now I see them regularly every summer in Vermont and Maine.

  The common raven, Corvus corax, like other American undertakers, experienced a vast reduction in its range and numbers after the extirpation of its food base, the carcasses of bison and elk, which had been available over vast stretches of the landscape. Ravens were ancillary kill at poisoned carcasses in the U.S. government’s war against predators such as wolves and coyotes. These birds were widely seen as undesirable characters, automatically on everyone’s blacklist for extermination, so their deaths by poisoning were deemed irrelevant. Ravens, however, had an advantage that vultures lack; part of their population had hung on in the far north, which still had large animal herds and few people: the north provided a nucleus for regeneration. Poems highlighting old European prejudices against the
raven as sinister and dour notwithstanding, the species is making a comeback as a respectable citizen, a valued co-occupant of our earth, and often a close neighbor. The ravens’ plight was dismal, but dawning awareness of these birds as intelligent beings endowed with emotions, vitality, and beauty has put an end to the mindless savagery.

  TRADITIONALLY, WHEN A great crime such as a murder occurs, people make a great effort to apprehend the guilty party. A murder is a great grievance, but it is a minor one compared to the loss of a species, especially one that is part of a cultural and ecological web that encompasses millions of people, performs ecological services on a near global scale, and enriches the enjoyment of life not just for the living but for all generations to come.

  Very few people intend evil; we always have an excuse for our actions. If a death is an unintended or unanticipated consequence, it is categorized as an accident. But accidents are seldom random. It may be an accident when someone drives drunk or goes through a red light in an urgent hurry and kills a person as a result, but it is not a blameless act.

  We are all guilty of causing extinctions; our standard of living, our massive industrial production, and our sheer numbers absolutely guarantee that we have a cumulative toxic effect on nature.

  What applies to people in the aggregate is true especially of their products. At one time, using a few chemicals out of nature’s apothecary was enough to supply our needs. Currently about 84,000 chemicals are in commercial use in the United States, and many are exported to other parts of the world. We don’t have any idea what even 20 percent of them are or if they are potentially harmful, because they (and their effects) are classified as “trade secrets.”