The Flight of the Iguana

by David Quammen

  What had changed? Why were a thousand belugas suddenly more precious alive?

  • • •

  I was still dialing that Soviet Embassy number, and they were still declining to pick up the phone. I checked back with directory assistance and tried again. No answer, no answer. At this point I began imagining things. Maybe it’s Lenin’s birthday and they’re all drunk. Maybe we’ve broken diplomatic relations, one of those gut-twisting international incidents, and the whole delegation has packed and left, headed back for an underground bunker in Moscow. Maybe the embassy was blown up by a crazed Azerbaijanian separatist.

  I called the Tass office in New York and finally got a human voice. Hi, I’m a journalist, just wanted to ask someone a few questions about . . . But I was too slow. The man sounded somber and nervous. He couldn’t help. He hung up.

  Next, the Soviet Consulate in San Francisco, and the fellow I caught there clearly thought I was either perverse or out of my mind, quacking at him about a bunch of ice-bound whales.

  “Izn’t it being a wrung time for zuch questions?” Deep, rich nasal accent. This one too sounded somber and nervous. Wrong time? I don’t know, why is it being a wrong time?

  “Becuzz now our president, he iz dead. And we are—”

  “Mr. Chernenko?”

  “Yez. Mr. Chernenko.”

  “Judas, I’m sorry. I didn’t know.” No TV and not having seen a newspaper for three days, just up here in my Montana snowdrift with whale books stacked around, I was evidently among the last several people in America to hear about it. I hung up.

  I went out to a newsstand. Gorbachev was already comfortably installed and making peaceable speeches. The disarmament talks were opening on schedule. The Soviet negotiators were in Geneva, ready to go, and they had their instructions—from Mr. Gorbachev. The vozhd is dead, long live the vozhd.

  I wanted to get that consulate fellow back on the line and say: Look here, it all seems to be settled. I can understand that you’re a little nervous about your own position. You might even be a bit sad. But now it’s time to talk about whales. Whales are very damn important also.

  I suspected he wouldn’t agree.

  • • •

  It seems to me there are two ways of viewing the incident at Senyavina Strait. The first is cynical and bitter. Since fairness demands that at least one Soviet voice be given ear in this essay (and since the various official Soviet spokesmen were so preoccupied and uncommunicative that particular day), I have turned to a quote from Yevgeny Yevtushenko. In a superb poem entitled “Cemetery of Whales” he has written:

  In the cemetery of whales

  by the hummocks of ice

  there are no sanctimonious flowers:

  the Eskimos have tact.

  Hey, Eskimo hunchback,

  white men have a funny custom:

  after planting the harpoon,

  they weep over the corpse.

  Murderers mourn like maidens,

  and tearfully suck tranquilizers,

  and parade in crepe,

  and stand honor guard.

  The professional hunters,

  who would look out of place,

  send wreaths to the whales

  from the State Bureau of Harpoonery.

  But the flowers are twisted together

  with steel cables and barbs.

  In applying a jaundiced view to the Soviets’ seemingly benevolent but contradictory behavior at Senyavina, it should also be noted that, back in 1970, some populations of Delphinapterus were discovered to be carrying high levels of mercury in their flesh. The Canadians abandoned commercial whaling for the species at that point. And the marketing of beluga meat was forbidden throughout the West—not on sentimental grounds, but on toxicological ones. As the commercial value of dead belugas declined, of course, it became less inconvenient to impute some level of preciousness to their lives.

  Nevertheless, the interpretation of Senyavina that I recommend is more optimistic, more forgiving, and arguably more ingenuous. All I can say of this second viewpoint is, Let’s try it on for the meantime. It is expressed by another poet, a non-Russian now, in a passage that has suffered even more overexposure than Pachelbel’s canon, but is equally weatherproof:

  The quality of mercy is not strained,

  It droppeth as the gentle rain from heaven

  Upon the place beneath: it is twice blessed;

  It blesseth him that gives, and him that takes . . .

  The intriguing part there, the part that remains fresh, is It blesseth him that gives. Shakespeare understood that the performance of an act of mercy can be, for the party who grants that mercy, a transforming experience. It can alter perspectives and attitudes, possibly. It can unite strong beings and helpless beings with a bond like no other: by making the very life of the helpless being into a shining emblem of the strong being’s decency, wisdom, restraint. In some cases it might even be habit-forming.

  It is twice blessed. A boon for those thousand belugas, certainly. Just as certainly, the Senyavina rescue had to be good in at least some minuscule measure for the Soviet nation’s collective soul—including even those bureaucrats who make decisions about icebreakers and whaling moratoriums. So by all means the best thing was to grant them congratulations, the benefit of the doubt, and a moment of pride. They deserved it. And maybe they will find that they enjoy the practice of mercy much more than anyone could have expected.

  AGONY IN THE GARDEN

  A Plague of Starfish Eat Their Way Through the Pacific

  It is one of the central axioms of ecology, held by most (though not all) scientists in the field, that the stability of an ecosystem is directly related to its complexity. The greater the number of species coexisting in one community, and the greater the number of relationships linking different species, so much greater will be the natural resistance to change, perturbation, catastrophe. From diversity comes strength; from variety, steadiness. So goes the axiom, anyway.

  In the case of tropical rainforests, which are considered the most complex terrestrial ecosystems on Earth, the axiom seems to hold true. Tropical rainforests (in the absence of serious disruption by man, at least) tend to be paragons of ecological stability, maintaining their balance of physical and ecological conditions over many thousands of years. Arctic tundra offers a good example of the same principle at its opposite extreme, a relatively sparse and simple ecosystem that is therefore also quite fragile. But in the case of tropical coral reefs—generally judged the Earth’s most complex marine ecosystems, the oceanic equivalent of mature rainforest—there is lately some reason for skepticism. The complexity-stability equation seems in doubt. The reason is a plague of starfish.

  Acanthaster planci is the species in question, an imposing echinoderm that grows up to two feet in diameter, with as many as twenty-one arms. It moves slowly across the sea bottom in shallow Pacific waters. It feeds on live coral. Its common name is the crown-of-thorns starfish, reflecting the tangle of long sharp protective spines that protrude from the dorsal surface. Each spine is tipped with a toxic mucus. Any such two-foot-wide bush of poisonous spines is, understandably, threatened by few natural enemies. Even a human diver who handles it risks a bad sting. Consequently, A. planci was considered a formidable species even back when it seemed to be quite rare. Nowadays formidable is an understatement and rarity is a puzzling memory. Something new has begun to happen. The ecological balance has tipped.

  In droves, in swarms, in startling multitudes, crown-of-thorns starfish are gobbling up the Great Barrier Reef. “There is a possibility,” one scientist has written, “that we are witnessing the initial phases of extinction of madreporarian [reef-building] corals in the Pacific.”

  The sudden abundance of A. planci has raised a few interesting questions. First and most controversially: Is this plague of starfish really so bad—and so unprecedented—as it seems? Expert opinion has been divided. Second: Has the plague somehow been caused by human actions? There is evidence to suppor
t this suspicion, but the evidence is mainly circumstantial. Studies to prove or disprove the human role are continuing at present. Almost everyone agrees that if the starfish plague has been caused by humankind, then firm measures should be taken to control it.

  The third question is rather more tricky, leading quickly from the solid realm of marine fieldwork and ecological evidence into the empyrean of philosophy, aesthetics, and balance-of-trade economics: If the plague has not been caused by humankind—if it has been an epochal but naturally triggered catastrophe, like a lightning-caused forest fire howling across Yellowstone Park—in that case, should anything be done to rescue those glorious coral reefs? Or should we let unsentimental nature, and the crown-of-thorns starfish, have their way?

  • • •

  A. planci has been infamous to marine biologists and scuba divers for more than twenty years, since the first public reports of its population explosion at a place called Green Island, just offshore from the city of Cairns on the northeastern coast of Australia. Green Island marks the approximate center of that long chain of individual reefs known collectively as the Great Barrier Reef, the largest formation of coral ever seen on Earth. For some decades Green Island has also been a focus of tourism to the Great Barrier Reef. The island’s facilities now include a pier, an underwater observatory in the midst of the coral, a gift shop, a cafeteria, a picnic area, a beach, and cheap daily boat service from Cairns. But the attractions of Green Island were abruptly threatened back in 1962, when it was discovered that unusual concentrations of crown-of-thorns starfish had begun feasting on the surrounding coral.

  Coral, like starfish, are animals. They belong to the same phylum as sea anemones, and in adulthood make their living as sessile creatures, attached permanently to a hard substrate, gathered together in large colonies of a particular species, each individual waving its tiny tentacles to capture planktonic food from the seawater. Their more famous attribute is that they secrete stony skeletons of calcium carbonate (lime) to support themselves. These lime skeletons—both those that still contain living coral and those that stand derelict—form the main structural matrix of coral reefs. Every reef is built up over a vast mass of compacted limestone, but it is the thin layer of live coral that keeps the reef forever renewed as a living ecosystem. That layer is precisely what A. planci at Green Island had begun to devour.

  From 1962 to 1964 the starfish population grew inexorably. The various species of stony corals were killed off in large swaths and patches. The starfish legions accomplished this at a slow but implacable pace, each single starfish destroying roughly a square yard of coral per month. The mode of attack was simple, and slightly grotesque. Climbing onto a coral surface, the starfish would evert its own stomach out through its mouth, pressing the stomach folds down among the hard coral branches, where its digestive fluids could dissolve the corals’ soft flesh; after absorbing its fill of those digested nutrients, the starfish would then pull in its stomach and lumber on. Behind the advancing front of starfish, which shuffled along like a herd of headless porcupines, were left dead coral skeletons that remained ghostly white for a few days or weeks, then gradually took on a gangrenous film of algae. The algae penetrated the lime skeletons and eventually weakened them, until normal wave action reduced the whole edifice to rubble. By that time, of course, the reef-dwelling fishes and other members of the coral community, dependent upon that edifice of lime for their cover, were long gone. A. planci, grown abundant beyond proportion, was literally collapsing its own ecosystem.

  The proprietors of the Green Island businesses hired divers to battle the infestation, and in little over a year the divers destroyed 27,000 crown-of-thorns starfish. The area of coral seen by most tourists was saved. But the plague hadn’t been conquered. On the contrary, eighty percent of the stony coral of the Green Island reef had been killed, and the starfish was now merely moving on.

  Until this outbreak at Green Island in 1962, no such episode—A. planci in huge numbers devastating a zone of live coral—had ever been reported in the scientific literature. Following the Green Island experience, though, marine scientists heard belatedly of a similar occurrence near Japan. A reef in the Ryukyus archipelago had suffered infestation in 1957, and more than 200,000 starfish were collected during a government-sponsored control program. Then, soon after the Green Island and Ryukyus reports, came a sequence of further outbreaks across the Pacific. Reefs were attacked at Guam, at Samoa, at the island of Molokai in Hawaii, at Palau and Fiji and Wake and New Guinea, off the coasts of Malaysia and Thailand and Okinawa. In the Guam case, during just two years in the late 1960s, ninety percent of the stony coral along twenty-four miles of coastline was destroyed. A control program was mounted there, and 44,000 starfish were killed. In Samoa, about the same time, a two-week roundup produced 14,000 starfish. Also at that time, 20,000 specimens of A. planci were counted on one section of reef at Molokai. Along the west coast of Okinawa, in 1972, the A. planci population was estimated at 210,000. All of these numbers, bear in mind, apply to an animal that was formerly considered rare.

  Exactly how rare it was can’t be known, in retrospect, but one team of scientists has written: “A month spent on a typical coral reef might have brought to light one or two specimens.” Another biologist reports that, in the old days, when she came upon a crown-of-thorns starfish, she would tuck it safely under a coral ledge—so that tourists might not find the poor thing and kill it. Now, just a few years later, money was being spent by worried governments and businessmen to exterminate A. planci by the thousands.

  Meanwhile, as hordes of starfish turned up in those far-flung places and new pockets of infestation appeared on the Great Barrier Reef, Green Island was left alone. The journal Science announced that “recovery is reported to have already begun; the island was free of starfish in 1968, and new colonies of four coral genera had become established.”

  See there, said the optimists. These fluctuations of A. planci population are merely a natural phenomenon, kept within bounds by the internal checks and balances of the reef community. One shouldn’t get too excited, they said. Most of all, one shouldn’t intervene in these natural cycles, on the ever-precarious basis of good intentions and incomplete knowledge. An ecosystem as complex as a coral reef, and as stable, can bloody well take care of itself.

  Or so went the hopeful assertion.

  But it wasn’t that simple. In 1979 A. planci came back to Green Island.

  Robert Endean, an Australian biologist who has been a leading authority on crown-of-thorns starfish for the past two decades, dived the Green Island reef that year and found that sixty percent of the coral had been killed—recently. He estimated the current A. planci population at 350,000. Since then, says Endean, things have gotten still worse. This time A. planci is not only killing the plate-coral and the branching-coral species. It is also killing the great massive brain-coral colonies, some of which are hundreds of years old.

  • • •

  There is a rough pattern to all those centers of starfish infestation that erupted across the Pacific during the 1960s and ’70s. The pattern is that A. planci appears in great numbers, generally, where Homo sapiens has also appeared in great numbers. The earliest outbreaks of the starfish plague have been focused mainly on reefs near those coasts and islands with considerable modern human settlement. This is the circumstantial evidence that points an accusing finger at humankind.

  What could the etiology be? What human actions could conceivably bring on a cataclysmic proliferation of starfish?

  The most logical guess is that we humans might somehow have released A. planci from the pressure normally exerted upon it by predators. Those missing predators might have fed on the eggs of the starfish, or on the free-swimming larval forms, or even perhaps (improbable as it seems) on the imposing adults, two feet across and armed with poison spines. Possibly there was a constellation of predators who fed variously on all three stages, thus keeping A. planci trimmed down to a sparse population, a mere h
alf dozen for every square mile of reef. Possibly. But no one knows.

  How might humanity have eliminated the predators? With industrial pollution? With insecticides, running off in erosional waters from the land? By dredging and blasting operations in crucial zones of coral? All of these notions have been mentioned in the scientific debate, and none of them seems very likely. But no one knows.

  Robert Endean, speaking by phone from his office in Brisbane, offers an alternative view. He suspects that the critical stage at which A. planci suffers predation (or in the more recent situation, the stage at which it should suffer predation but doesn’t) is neither as eggs nor as larvae nor as full-grown adults. Instead, Endean posits that the post-larval juveniles might be the preyed-upon form. At this stage the animal has reached its adult shape but not its adult size. It is a miniature starfish, just an inch or a few inches across, a convenient morsel for a fish or a large snail, and the long potent spines have not yet developed. In the juvenile stage, Endean says, A. planci could be quite vulnerable to a whole constellation of predators, species such as are native to coral reefs in an undisturbed state. Among those predators would be the giant triton, Charonia tritonis, a snail-like gastropod that grows twenty inches long and has been seen feeding on crown-of-thorns starfish. Also included might be such fishes as the hump-headed wrasse, the spotted toado, several types of triggerfish, groupers, coral trout, and a number of other reef-dwelling species. Taken together, the pressure of predation by these animals upon A. planci in its juvenile and small-adult stages might be just adequate to keep the starfish at low population levels. Taken away, those animals by their absence might explain the A. planci plague.

  And, according to Dr. Endean, precisely those animals have been taken away by human activities in places like Green Island. Beginning back in the 1950s, the giant triton has been collected by the tens of thousands for its beautiful shell, which was sold to tourists as a souvenir. The various predatory reef fish have been drastically reduced by spear-fishing divers and commercial fishermen. Some of those predators were probably specific, focusing on A. planci to the exclusion of other prey. Some were no doubt generalists, eating juvenile A. planci among other things. One result of their combined disappearance, suggests Endean, is a population explosion among starfish.