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For additional information, see the Global Shipping Program terms and conditions - opens in a new window or tab. Start of add to list layer. Add to Watchlist Add to wish list. Sign in for more lists. The animals are not endangered — their health is. Several years ago, it was discovered that if young adult female elephants do not get pregnant quickly, they develop leiomyomas. So if elephants are being kept in zoos and, like it or not, they are , something must be done to get females pregnant, and quickly. Males are much more dangerous than females — so most captive elephants are female.
Transporting the occasional male around the world for each liaison is not practical. A courier service to take sperm from one group to the other is the only way they are going to reproduce. Incredibly, this can be done without anaesthetizing the elephant, and perhaps because of the pleasurable sensations associated with the massage, bull elephants will tolerate it really quite well — far better than someone trying to take a blood sample, for example.
So well, in fact, that this can be performed up to five times a day. Any contact will elicit an eager search for the vagina, he says. Touching a penis is not helpful. She began by practising on tortoises less precious than Lonesome George. Routine was important. Eventually she could stroke his shell without him withdrawing into it. Every day, she washed herself with a neutral soap to reduce her human scent that might be a tortoise turn-off.
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Then she covered her hands with genital secretions from the Isabela females. These may have contained sex pheromones — sexually charged odours that pass between individuals of the same species. The classic sex pheromone is bombykol, the devastatingly alluring chemical released by female silkworm moths to entice males from great distances. A surprising experiment involving smelly T-shirts even suggests that humans produce sex pheromones that could be important in choosing a suitable partner.
In , evolutionary biologist Claus Wedekind handed out a small cardboard box to male volunteers. Inside was some perfumefree soap, a T-shirt and a short list of instructions: they were asked to wash thoroughly using the soap, wear the T-shirt non-stop for two days without washing again , return it to the box and shut the lid — phew!
Female volunteers were then asked to sample the odour of six boxes chosen at random and judge which they preferred or, more probably, disliked the least. Wedekind found that women would consistently select smells from men with different immunity genes from their own. Sniffing out genes in this manner could be a useful way to give children the most robust genetic start possible, he suggests. Sex pheromones also carry information between individuals of the same sex. A rather startling experiment in sheep demonstrates this quite nicely.
Good-humoured Grigioni succeeded where nobody has before or since. Second, she got him to begin showing signs of sexual activity. She had to return to Europe to begin her doctorate. When Grigioni left, he slowly returned to his former stubborn ways. He and his female co-habitees have free rein over a comfortable area of the research station. There is plenty of vegetation in which George can find the privacy he evidently seeks, tree-like cacti, a shelter which he uses during the hot season and a large pool wherein he is free to bathe should he wish to venture out into the open.
And at some distance, his fans — the tourists — skirt respectfully around. The best days to visit are Mondays, Wednesdays and Fridays. George likes his food and these are the days when he is fed. When the warden enters his enclosure bearing edible gifts, George will march out from behind shrub cover to meet him or her, brimming with hungry confidence. Then, and often only then, it is possible to get a really good look at his impressive kg bulk. Giant tortoises are striking creatures.
Book Review: Lonesome George: The Life and Loves of a Conservation Icon
How on earth did they get there? During the 19th century, several radically different solutions to this conundrum came and went. For some, this journey seemed just too incredible. Amongst much else, he wanted to know if giant tortoises could have survived the km journey from the continent. He became one of very few people to have tested the seaworthiness of a giant tortoise. Figure 3. They lashed the unfortunate reptile onto poles and carted it slowly over the terrible lava, through the thick growth of cacti and thorny plants to the shore.
On the beach, Beebe watched as several members of his search party lifted the tortoise into a rowing boat wedged into the sand. Although it was now dark and the temperature had fallen, this was tough work. He removed his cloth hat and mopped the sweat from his balding brow. One by one, the team clambered aboard. Beebe found himself cramped beside the tortoise, his tall, thin frame bent double. He let a hand rest atop its shell. The following day, they rowed the tortoise back to land, this time to nearby Santa Cruz.
There, they set about filming it performing various tasks. First, they let it loose on a steep, rough lava slope to see how it coped. As the rowing boat drew up alongside the Noma, they heaved the giant tortoise up and over the edge into the water. Then its neck emerged to full length, raising its head well above the waves, and the top of its shell bobbed back up and out of the water. This was no better. Beebe repeated the experiment several times, getting the same result on each occasion.
The body was somewhat wasted, but hardly enough to account for so sudden an end in a slow-living, slow-dying animal. A post-mortem settled the matter.
Lonesome George: The Life and Loves of a Conservation Icon
The tortoise had congested lungs, suggesting that it had swallowed too much salt water during its marine ordeal. What alternative explanations were there? Then in , George Baur, a German-born scientist at Yale, put forward a controversial alternative theory. It came to him in the university museum as he unpacked fossils from a recent field trip to Nebraska. Among the specimens were giant tortoise fossils.
Tortoises walked there, he reasoned, by way of a land bridge, which has since sunk into the sea. Occasionally, a hot spot under a plate will break through and spew molten rock or magma onto the surface to form a volcano. As the plate moved over it, drifting from west to east, so island after island emerged from the sea, lifeless larval outbursts forming the archipelago that we see today.
The oldest volcanoes, which have long since drifted off the hot spot, have been eroded from towering mountains to low and barren islands. Detailed surveys of the Pacific Ocean between the existing archipelago and the South American mainland also reveal a string of drowned islands, so weathered they are covered by waves. Working more than half a century before the discovery of plate tectonics, Baur did not know this. The sink-or-swimability of the tortoise became central in their argument. Tortoises are unable to swim, pronounced the recalcitrant Baur.
Even if one did manage the epic journey, it would never be able to establish a population. As they drift east, off the hot spot, the islands are weathered down, eventually beneath the waves Similar objections continued to resurface for decades. On 17 March , four members of the expedition were on Isabela looking for tortoises. They spent much of the day on their hands and knees, crawling through dense scrub near the shore.
The colossal weight and a freak wave caused the boat to capsize. The swell smashed it into a thousand pieces and carried the tortoises out to sea. A few pieces of broken skiff drifted past the anchorage, followed by one giant tortoise and then the other. The unfortunate creatures seemed none the worse for their 18 hours at sea. By then though, this was a minority position. The geological evidence for a volcanic origin of the archipelago was stacking up.
In , the British geologist Charles Lyell proposed that small, matted islands of fallen trees, floating out at sea, could carry all manner of plant and animal life to all sorts of remote places. Charles Darwin, the naturalist who accompanied Fitzroy on the Beagle, certainly thought so. Some time after his return to England in , he set about experimenting with seeds and sea water to work out whether they might survive a long journey at sea. By the time he published On the Origin of Species in , he had exposed the seeds of 87 different plant species to his sea water concoction.
Incredibly, nearly all of them germinated after weeks stewing in brine; some still seemed in perfectly good working order after several months. It certainly looked as though seeds might be able to survive at sea. There was one snag. Almost all the seeds sank, so would never have floated very far from a continent like South America. Darwin thought a bit more. Seeds are much more buoyant when dry. Seeds of other plants might be transported in the intestines of dead animals and yet others could be carried by live birds, either in their crops or perhaps in earth caked onto their bills or feet.
Here were four plausible mechanisms of seed dispersal, each backed up by elegant experiments. And there were undoubtedly more, Darwin admitted. What about its fauna? It is simple to explain how animals with wings reach distant places. Indeed, almost all islands have birds and bats. But working out how earth-bound animals reach isolated islands is not so easy. He ignored them. He was more interested in explaining why certain groups of animal were so scarce on remote islands. If terrestrial mammals had trouble surviving at sea, which seemed possible, this would explain why remote islands are such mammal-free places.
As usual, Darwin was essentially spot on. It has two species of frog. The assumption was that humans brought them to the island.
DNA evidence indicates otherwise. The Mayotte frogs are like no other species on earth. Not only are they genetically distinct from those on Madagascar and the African continent, they are distinct from each other. This suggests that frogs reached Mayotte on two separate occasions and, because of the isolation that island living provided, they evolved into the two unique species we see today.
They are colonized, in other words, only by those species that manage to survive a journey over open ocean. This scuppered the idea of a land bridge. Townsend laid out the case for the migration of tortoises on the prevailing westerly currents. These mainland tortoises were not giants, but with some recorded at over 60 cm in length, they were not small either. Such ideas were impossible to test, until the advent of DNA profiling in the mids, that is. Geneticists at Yale University collaborating with a host of others around the world got on the case in the s.
The red-footed tortoise T. Instead chimps and humans sit near each other on the primate family tree, like leaves on two neighbouring branches. But we do know that it probably lived between 6 and 12 million years ago. This process, known as gigantism, is common on isolated islands; it left some very large creatures in some very small places, although many of these are now extinct.
DNA collected from museum specimens suggests that this strange bird evolved from a pigeon-sized ancestor. Giant tortoises are often wheeled out as another case of island gigantism. Southern Australia is home to several populations of highly venomous tiger snake. Most are of a fairly standard size. On several small islands just off the coast, however, the tiger snakes are huge, reaching up to cm long and weighing well over 1 kg.
Those on Mount Chappell Island, for example, can weigh twice as much their relatives on nearby Tasmania only around 50 km away. What is there to stop tortoises undergoing a similarly rapid change in body size? Not a lot, it seems. They usually reach their maximum size by the age of A few minor mutations of one or two genes might be enough to cause a startling change in body size. But did this occur on the islands, as most assume? Not necessarily. The fossil record reveals that there were giant tortoises living on the continent until about a million years ago. These hefty creatures would have stood a much better chance of surviving the perilous journey to the archipelago than would regularsized animals: giant tortoises have good fat reserves, can extend their necks above waves and are better equipped for life in a hot, dry, boulder-strewn world.
Geological evidence shows that this remote atoll was completely submerged around , years ago. It only re-emerged about , years ago, yet today is covered with giant tortoises. It is unlikely that small tortoises could have gone large in such a short time. The mainland tortoises were by now of immense proportions.
There are, of course, other plausible scenarios. Either iguanas reached the archipelago on two separate occasions or they made it out to the islands only once and subsequently evolved into the land and marine forms that we see today. Once more, DNA differences shed some light on the matter.
The land and marine iguanas are more closely related to each other than either is to any mainland iguanas. This suggests that the fork in the iguana family tree took place on an island and not on the South American continent. Unless, that is, the fork between the land and marine branches of the iguana family tree took place on intermediate islands that have long since weathered away.
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If iguanas used such island stepping stones, why not giant tortoises? The rest is evolutionary history. This has produced some commonsensical results plus a few surprises. There has been a lot of often very heated debate over the similarities and differences between the tortoises from different islands and volcanoes and whether they constitute just one or several distinct species. Even if everyone agreed that the tortoises from the different islands were just one species, conservation biologists would still do their best to preserve the genetic integrity of each population.
In certain situations, however, the survival of a species can be influenced by its name. Biologists name the animals and plants around them to bring some sense of order to the natural world. A cat and a dog are put in the same room, but in different aisles; a lion and a tiger in the same aisle but on different shelves. Only different types of tiger such as Bengal, Sumatran and Siberian will be together on the same shelf. This can be disastrous. In , scientists identified two species of tuatara in New Zealand, a rare lizard-like creature found nowhere else on earth.
So 20th-century conservationists trying to protect these unique creatures saw just one and not two distinct species. This ill-informed management probably led to the extinction of several important populations. Fortunately one small population of the second and less common tuatara described back in survives on a group of tiny islands to the east of New Zealand.
In short, bad taxonomy can kill. Three — on the islands Santa Fe, Floreana and Fernandina — are extinct. Eleven types survive, one of which is the Pinta tortoise. If Lonesome George really is the last of his kind, only 10 different types of tortoise will remain once he dies. Here each inhabits its own volcano, isolated not by sea but inhospitable stretches of barren lava.
Given a few more million years evolving in isolation, each of these subspecies should eventually attain full-blown species status: they would be too different to mate successfully. For now, while they are still able to interbreed, the different types are referred to as subspecies. The extinction of the Pinta subspecies, say, would leave a gap on the shelf that could never be closed.
As geneticists probe with ever increasing sophistication, the established tortoise taxonomy is likely to change. For example, there are two main populations of domed tortoises on Santa Cruz, all deemed members of the same subspecies Geochelone nigra porteri. In , the Yale geneticists performed the first detailed inspection of DNA from these two populations. The researchers found differences so great that, in a Biology Letters paper, they called for a significant revision of tortoise taxonomy.
Such a revision could influence the management of tortoises on Santa Cruz.
One lineage, in particular, is at greater risk of disappearing than the other. The population at Cerro Fatal to the east of Puerto Ayora has suffered considerable poaching recently. Farmers have also whittled away its habitat. An appreciation that this population carries a unique set of genes makes it even more important that conservation biologists do all they can to protect it.
This was code. It was written in such a way as not to offend the majority of his readers who believed that God created the earth and everything on it. But for those seeking an alternative to the Bible story, this passage and others like it were a nod and a wink.
Darwin of course had more to say on the origin of species. His book on the subject changed forever the way that we think about the natural world. Far from it. During this time the Male utters a hoarse roar or bellowing, which can be heard at more than yards distance. Hence, probably, urged by a fixed and hereditary instinct that the shore is its place of safety, whatever the emergency may be, it there takes refuge. Figure 4. If he did see any live tortoises on either Floreana or Isabela, he made no mention of it.
The Floreana tortoise was already on the brink of extinction and although tortoises do come down to Tagus Cove, they were probably not there in the dry season when Darwin passed through. They were so heavy, I could scarcely lift them off the ground. The effect is very comical in seeing these huge creatures with outstretched neck so deliberately pacing onwards. Lawson maintained that he could at once tell from which island any one was brought.
My attention was first called to this fact by the ViceGovernor, Mr. Lawson, declaring that the tortoises differed from the different islands, and that he could with certainty tell from which island any one was brought. I did not for some time pay sufficient attention to this statement, and I had already partially mingled together the collections from two of the islands. I never dreamed that islands, about 50 or 60 miles apart, and most of them in sight of each other, formed of precisely the same rocks, placed under a quite similar climate, rising to a nearly equal height, would have been differently tenanted.
No one is sure how they managed it. They do, however, take the odd tumble when negotiating a rocky incline.
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Perhaps some tortoises, especially the smaller ones, primarily females living closer to the coast, never made it to higher ground but were washed to sea, she says. Currents would then have carried them out to sea and with a bit of luck onto the shore of a neighbouring island. After many generations, the original and the new tortoise populations would begin to look and behave differently.
This divergence of populations occurs, in part, because the machinery that copies DNA to make sperm and eggs is not infallible. Sometimes a photocopier will make three copies when you wanted one, sometimes it will make none and occasionally the copy will come out looking grey, blotched or bleached.
Two machines will not produce the same catalogue of errors in the same order over the same time period. If you keep copying the same document on two different machines, eventually there will be a version that differs from the others. Make more copies of this tweaked copy and more differences will accumulate. Similarly, mistakes occur when DNA is replicated. Two tortoise populations that start with identical genes but reproduce in isolation will eventually accumulate genetic mutations; the populations will drift apart and may begin to look and behave differently. There are also non-random genetic changes over time, usually because certain genetic combinations are, by chance, more or less suited to a time or place than others.
Although Darwin did not immediately realize it, subtle differences between islands can winnow particular characteristics. The larger islands that rise up to mountainous peaks have lush highlands — their tortoises have the default dome-shaped shell which is fine for an easy-going grazing lifestyle. Here, where there is little to browse on, tortoises have a furled lip at the front of their shells and long necks, enabling them to reach up and nibble at shrubs or cactus pads. They could eat more, were less likely to die if the going got tough, so stood more chance of having babies.
And after many many generations, long-necked tortoises with saddle-shaped shells came to dominate. But most, he warns, are difficult to tell apart. So little was Darwin impressed that he not only failed to collect scientific specimens of the creatures, he apparently helped his Beagle shipmates tuck into the last of some 30 large tortoises during the cruise to Tahiti. At dawn on 19 October , the Beagle — with Darwin on board — sailed, without stopping, past Pinta and out of the archipelago. The idea is that the longer two populations have been apart, the more time they have had to acquire genetic differences.
A few pioneers were lucky enough to be washed up on another island. The next stop was probably Santa Cruz. Once a population had established itself there, the same thing most likely happened again. Some animals from Santa Cruz were washed out to sea and survived the hop to a neighbouring island. In sum, it seems that tortoises slowly spread throughout the archipelago, making one relatively short and plausible journey at a time. There are two fairly discrete populations — Puerto Blanco on the northern slope and Puerto Bravo on the western slope of the volcano.
Most of the tortoises here have domed shells and seem to have come from the island of Santiago just 50 km away. In , Adalgisa Caccone and Jeffrey Powell, codirectors of the Yale group, led a study of DNA from 22 Wolf tortoises and found that several are clearly not direct descendents of the Santiago tortoise. Pirates and whalers often stopped off at the southern islands to stock up on tortoises.
Sail ho! It was to be a rewarding day for the skipper of the infamous US frigate Essex. That April morning, he came to the bridge and swept the horizon with his telescope until he had the strange sail in his sights. It was a British whaler — the Montezuma; Porter ordered his crew to give chase. These, he was told, were two other British whalers, the Georgiana and the Policy. Porter gave chase once more. He learned from the captain of the Montezuma that the Georgiana had 35 men on board and carried 6 large guns; the Policy had 26 men and 10 smaller guns.
Their only hope was to blast the small boats out of the water. They were woefully unprepared, particularly as they had just stocked up on tortoises, which were getting in the way. Farragut was in one of the rowing boats closing on the Georgiana: The appearance of these [land] turtles in the water was very singular; they floated as light as corks, stretching their long necks as high as possible, for fear of drowning. They were the first we had ever seen, and excited much curiosity as we pushed them aside. As Farragut and his fellow men picked their way through a sea of giant tortoises, the cannon fire began.
The boats now formed in one division, and pulled for the largest ship, which, as they approached, kept her guns trained on them. They were rounded up and brought on board. He and his crew ate these tortoises in the coming months, but presumably some of those jettisoned by the embattled British ships were never recaptured.
One or two, perhaps, made it to the nearest shore. This story neatly illustrates how human activity could have contributed to the movement of tortoises from island to island. While most of the Santa Cruz reptiles have dome-shaped shells, the Cerro Montura tortoises are saddlebacks. How come? Alternatively, and probably more likely, this could be another example of human meddling. DNA throws up an even greater puzzle though. Whilst most of the islands seemed to have been colonized in steppingstone fashion, there is one notable exception — Pinta.
Before the Yale group delved into his genome, it was widely assumed that tortoises had reached Pinta from the northern tip of Isabela. This, after all, is the island closest to Pinta that has tortoises. The Yale geneticists did. Worried that the blood sample from Lonesome George had somehow been contaminated, Caccone put the analysis on hold until she could get more blood.
The following year, she extracted DNA from a fresh sample and reran the analysis. The result was exactly the same. Back in , protein analysis suggested that the lizards on Pinta were most closely related to those on southerly Floreana. More recent work using current molecular techniques presents a more complex picture. Perhaps the Pinta population really is extinct and the animal found in is a recent visitor that somehow found his way from island to island.
This argument is difficult to test. A handful of tortoises that we know were collected on Pinta in the 19th and early 20th centuries wound up in museums. Despite repeated efforts, only two of the three tortoises yielded any DNA and the sequence from these two samples did not match that of Lonesome George. This suggests that our celebrity tortoise could be an introduction, Louis says. Worrying stuff. If Lonesome George is an impostor from another island posing as a Pinta tortoise, he has fooled millions. This same concern occurred to Caccone and her colleagues.
Matching up DNA fragments is rather like trying to do an incomplete jigsaw. If you have very few pieces, it is difficult to see the overall picture — to realize say that the dome and minarets are from the Taj Mahal. If you have almost all the pieces, you can be pretty certain. The Yale group recovered about three-quarters of the genetic sequence from the museum specimens, enough DNA to be confident that Lonesome George is from the same population as the other animals collected from Pinta.
On balance it looks like Lonesome George fully deserves his hard-earned celebrity status. Flagship species are charismatic animals or occasionally plants that stimulate conservation awareness and action. A successful flagship need only operate in the world of marketing and public relations. It need not even be endangered if it achieves something for conservation. The brightly clad visitors crouch respectfully beside captive tortoises; the only sounds are a rhythmic munch from the animals, the pregnant click of camera shutters and soft words from tanned guides in khaki shorts.
Each guide leads their group onwards to the succession of pens that house tortoises from hatching until they are old enough to be returned safely to their own islands. And at the end of the trail through the research station, the tourists get a few minutes to commune with Lonesome George. What makes a good flagship? There is something going on in this hierarchy.
Not only do mammals have fur, so can easily be rendered cute and cuddly, they also have facial features that are not dissimilar to ours. Humans respond positively to fluffy, anthropomorphized animal caricatures. Up until the 19th century, breeding avocet were a common sight in the marshes and fens of eastern England.
By , they stopped breeding in the region owing to extensive draining of land to reclaim it for agriculture. Today, between and pairs breed along the east coast each year. The giant panda is the perfect example. Most captive individuals have names and are treated as honorary humans by zoo staff and visitors alike. The panda is also highly endangered. This winning combination has made giant pandas the star attraction at zoos the world over for more than 50 years.
They became a symbol of the new friendship between the countries and were a huge hit at the National Zoo in Washington DC. London Zoo decided to give Chi-Chi asylum and she was an instant hit with the public. Chi-Chi is now immortalized as the symbol of global conservation. Only a few individual animals have become brands in this way.
Elsa, the lion cub reared in captivity and subsequently set free by Joy Adamson, had the same combination of public appeal and a message. During the mining boom of Figure 5. When they packed up their pick axes and tourism took over, they set the donkeys loose. By , when the canyon achieved national park status, these introduced animals had become a real tourist attraction.
One of them — a friendly, pancake-eating, crowd-pleasing beast called Brighty — soon achieved celebrity status, inspiring people to visit and value the canyon. Sadly, Brighty disappeared during the winter of , shot and eaten as legend has it by two starving travellers who failed to recognize the iconic burro. Nevertheless, he became the subject of a series of best-selling books published in the s and a shiny-nosed bronze statue of him sits in the entrance hall of the Grand Canyon Lodge on the northern rim of the canyon. Like Chi-Chi, Elsa and Brighty, Lonesome George is a celebrity with the double whammy of charisma and a conservation message.
His one-of-a-kind condition and his reclusiveness are things people can relate to — his story triggers a sympathetic response. And the fate of his subspecies echoes the fragility of endangered living things everywhere. For Melville, as for others before him, these were haunting islands. The first person brave or crazy enough to think about living there was an Irishman, Patrick Watkins, marooned on Floreana in Only the eccentric Watkins felt the urge to spend any serious time there. This triggered the first serious attempts to colonize the archipelago.
He wanted to harvest and export the abundant lichen Roccella tinctoria, a good source of a purple dye called orchil. He failed. In , his workers rebelled and murdered him. At the beginning of the 20th century, there were still only around inhabitants in just a few settlements. The archipelago remained similarly uncivilized until the middle of the 20th century. Tourists mean money. There was no looking back. The number of MAN TRAP 79 ecotourists visiting the islands and the size of the resident population required to service them have continued to rise hand in hand.
This in spite of concern over the number of tourists that the islands can sustainably hold. By , this notional limit had been exceeded. At the end of the 20th century, some 80, tourists were entering this fragile, unique ecosystem every year. Taking a plant or animal out of its natural setting to another place frees it from its natural web of pests, predators and competitors for food and space.
Thus unencumbered it can be unstoppable. Figure 5. The rabbits took to their new home and at first everyone was delighted. The bunnies razed vegetation and caused untold damage to precious crops; they pilfered the food and annexed the burrows of native marsupials like the greater bilby and the burrowing bettong.
Today, the annual cost of production losses and control measures is somewhere around a million US dollars. Then came the cane toad Bufo marinus, introduced from the Americas. In , toads were released in Queensland to control the greyback beetle that was devastating sugar cane crops. Anything that eats a cane toad gets a nasty surprise: poison is released from glands behind its head. Red-bellied black snakes were hit hard, and with a decrease in the abundance of red-bellied black snakes, there was an explosion of rodents and grasshoppers.
Birds like the pheasant coucal, white-faced heron and eastern swamp hen have all been disturbed by the toad; and native amphibians such as the white tree frog are snaffled up by the non-native. Australian scientists continue to work on ways to prevent the southern advance of this species. The latest alien tragedy for Australia comes in the unlikely form of an ant. They cause trouble for native ants; they eat land and freshwater snails and sting all sorts of amphibians; they devastate clutches of turtles, lizards, snakes and crocodiles and happily feed on newly hatched birds.
Large mammals like pigs and goats have had the most obvious impact, more of which anon. In addition, several less conspicuous mammals, a handful of reptiles and birds, scores of invertebrates and hundreds of plants have reached the archipelago with a helping hand from humans. Some of these have had a dramatic effect on native species.
What follows is just a taster. On every island infested by black rats, the native rice rats have gone extinct. Every island that is except Santiago, where the small rice rat population was rediscovered in The parasitic fly Philornis downsi probably arrived in the islands some time in the 20th century. Platt is the editor of The Revelator. An award-winning environmental journalist, his work has appeared in Scientific American, Audubon, Motherboard, and numerous other magazines and publications.
His "Extinction Countdown" column has run continuously since and has covered news and science related to more than 1, endangered species. John lives on the outskirts of Portland, Ore. You have free article s left. Already a subscriber? Sign in. See Subscription Options. Platt John R. Load comments. Get smart. Sign up for our email newsletter.
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