Ark on the Move
Because of habitat destruction by man and the repeated attention of cyclones, there were two species of creatures found in Rodrigues which urgently needed help. One was the delightful and delicate little Rodrigues fody, a small yellow, orange and black bird which was, a hundred or so years ago, very common on the island. But with the steady disappearance of its habitat, combined with the introduction of the much tougher and more adaptable Malagasy fody, who competes for the meagre food supply, this attractive little bird was in dire straits. Then came the diabolical Monique, and when she—cat-like—had finished playing with the island and had passed on screaming into the ocean, there were only six pairs of fody left alive, only twelve, small fragile birds left to continue the species. It seemed touch and go but then the fody had some luck. The various cyclones, for a few years, left the island alone. During this time of peace the little bird managed to build its numbers up to over one hundred pairs. This was wonderful but we all wondered what would happen when the next cyclone struck. Was it not possible that it might be more devastating than Monique? As a precautionary measure the Mauritian Government decided to let us take six pairs back to Jersey to set up a captive breeding colony. Now, on our return two years later, the wild population had had another period of cyclonic attention and so we were anxious to visit the island and see how they had stood up to this pressure.
The other species on the island that gave cause for concern was the lovely little fruit-bat, which is probably the rarest bat in the world. In 1976, we estimated that the total world population was between 120 and 130 specimens and so—again as a precautionary measure—the Mauritian Government asked us to catch a sufficient number to start two breeding colonies, one in Jersey and one in the aviaries at Black River. Our Jersey colony had flourished and had grown from the original ten specimens to over thirty, but nevertheless we felt it would be helpful to our breeding success to obtain one or two more specimens on this visit, to extend our gene pool.
Rodrigues lies 360 miles from Mauritius and the flight to its tiny airport takes you over the vast blue carpet of the Indian Ocean. As you watch the brilliant blue expanse below it reminds you vividly of how much of the world is covered by water. After one hour’s flying you can just discern a faint brown smudge on the horizon which is the island, and as you get closer, you can see the brown eroded landscape, the tiny, pathetic pockets of green in the valleys and the whole island encircled by a vast reef on which the waves break continuously in a crumple of foam like a giant lace cuff protecting the island.
Rodrigues now seems so desiccated, so dry, so lacking in forest that it is hard to think that when it was first settled by a group of nine Huguenots, escaping from persecution in France in 1691, they christened the settlement Eden because of the rich bounty the island offered. Among these first settlers was one Francois Leguat, an astute observer, and it is from his written descriptions of the island as they found it that allow us to imagine what a magical place it must have been.
To begin with, the island was thickly forested with hundreds of species of tree and shrub, so when the seeds the settlers had so carefully brought from France refused to grow it scarcely mattered, for nature on this paradise was rich and bountiful. Fruits and vegetables grew everywhere in profusion. The settlers made wine and spirits from the palm trees. The vast, frothy apron of the reef, exposed for miles at low tide, teemed with thousands of fish, oysters, lobsters and crabs. In the lagoons, feeding on seaweeds, were herds of massive, placid and easily killed dugong, the huge marine mammal rather like a seal, whose flesh was delicious and whose carcass yielded valuable oil. Nor was the interior of the island any less bountiful. Bird life was abundant and, having no enemies, the birds were tame and easy to kill. Especially easy in this respect was a turkey-sized flightless bird called the solitaire, which like the dodo was soon to become extinct. The island was also full of a species of giant tortoise, each one the size of a large armchair, that ambled in their thousands through the forests. So common were these huge reptiles that Leguat wrote, ‘Sometimes you can see two or three thousand of them in a flock, so that you may go a hundred paces on their backs without setting foot on the ground.’
Alas, the arrival of the settlers was the death knell for this wonderful island. The settlers themselves did not stay long for, in spite of the richness of the island, the lack of feminine companionship drove them to Mauritius. But the tales they told of their Eden soon had ships calling at Rodrigues, and, as man has always done, the island was raped ruthlessly and unmercifully. The forests were felled for timber. The birds and the dugongs were harried to extinction, as were the tortoises. Ships would call in and take thousands of tortoises on board as living meat supplies, such as a modern vessel may take on tinned hams. Very shortly the animal life dwindled and was gone. The forest vanished and this ‘Garden of Eden’ lay an eroded husk after the locust like attack of man. Thus in three hundred years man, through thoughtless greed, had turned a rich and beautiful place into what is today, almost a desert, the home of some 35,000 people who eke out a marginal existence as fishermen or small farmers who carry out a desultory trade with Mauritius.
Although, ecologically speaking, Rodrigues may be considered a disaster area, it has the charm of a small, remote and sunlit island, inhabited by gentle, friendly people. We drove into Port Mathurin, the pocket handkerchief-sized capital, and then up the hill to the long, low, slightly ramshackle building with broad verandahs looking out over the blue sea that is Rodrigues one and only hotel. Here we unpacked our gear and then, taking the Forestry Department’s Land-Rover, we drove up for a reconnaissance to the place where the bat colony lived, the picturesquely named Cascade Pigeon.
Here, lying on the sides of a deep valley, was one of the last remnants of forest in Rodrigues. It was not very tall or very dense; but in the middle of it, on one of the flanks of the valley, grew a small grove of old and luxuriant mango trees. It was in the deep shade of their glossy green leaves that the Rodrigues fruit bat had its home and its last stand against extinction. At first glance through the binoculars the uninitiated might be pardoned for thinking that the mangoes were possessed of a crop of strange, wind-fluttered, furry, chocolate-coloured fruit. But as the bats yawn and stretch their wings the illusion is dispelled. Now you can see that with their leathery dark wings and their fur that ranges from deep fox-red to the colour of spun gold, they look like some wonderful miniature flying teddy bears, a resemblance that is helped by their bear-like little faces with button noses and round, bright eyes.
Most people have a fear of bats that is quite irrational, presumably to a large extent helped by the tales of Count Dracula and his ilk. But in reality they are charming, intelligent little creatures, the only mammals possessed of true flight, and to see them at Cascade Pigeon, as they lazily wheeled and flapped their way from tree to tree, was to realise how extraordinary and graceful an adaptation it is.
Fruit-bats, unlike their useful insect-eating relatives, are not equipped with built-in sonar. They have to detect their food by their acute sense of smell. In order to catch them we planned to use, as we had used on our previous trip to Rodrigues, a variety of fruits brought over from Mauritius (there were no such luxuries in poor, desiccated Rodrigues). In our extensive array of bananas, mangoes, guavas and the like was a malevolent fruit known as a jackfruit. This green, warty, watermelon-sized fruit is considered by both some human beings and all fruit bats to be a rare delicacy, and it is difficult, if not impossible, to imagine why. Its smell is sweet, sickly, cloying and clinging, and is a happy cross between an open grave of some years’ standing and a thoroughly blocked up sewer. We kept this ghastly fruit tightly swaddled in plastic, but even so the scent—if that is not too enthusiastic a word—leaked out and permeated everything. At the airport in Mauritius people coughed furtively and eyed us with suspicion. Within minutes the interior of the plane reeked of jackfruit to the consternation of other passengers. Arriving in Rodrigues we and all our equipme
nt smelt of nothing but the all-pervading jackfruit. Even Lee, in spite of lavish applications of Eau de Cologne, gave off an almost tangible shimmer of effluvium and put a grave strain on our marriage.
Our plan was to hoist all the fruit aloft in a clearing near the bat colony and then surround it with mist nets into which (as had happened last time) the bats would blunder in search of the bait. We finished the trap by nightfall just when the bats, with much squeaking and chattering and wing-flapping, were making ready to fly off down the valley in search of food. Then we concealed ourselves in the bushes and waited, for you cannot simply leave a trap like this and return in the morning after a refreshing night’s sleep. You would probably find any bats you had caught had damaged themselves with their struggles to get free and some might even have strangled themselves. You have to stay all night by your nets ready to cut the little bats loose as they are caught. So we settled down, the jackfruit reeking like a charnel-house thirty feet above us, to while away the time with what appeared to be the entire mosquito population of Rodrigues.
Collecting wild animals is, to say the least of it, unpredictable. You may strike lucky straight away, or you may hunt the forest for days fruitlessly, only to find that a maid had caught you the animal you want under the bed in your hotel. This occasion was one of the frustrating examples. Three tiring, mosquito-ridden nights later, all we had caught was one bat—a male, moreover, which was useless to us. But the reason the bats were ignoring our odoriferous fruit bait was, we thought, a good one. In the last few years the island had received an unprecedented rainfall, and in consequence what was left of the forest had flourished and expanded marginally so that the bats now had a wider variety of feeding areas. From a conservation point of view, this was, of course, excellent news, but it was a little difficult to be too enthusiastic at three o’clock in the morning when you were sharing your red corpuscles with a lot of voracious mosquitoes.
So we failed with the bats. But we were more successful with our second task, which was to try to do a census of the fody to see how its numbers were faring. It was here that Lee came into her own, for, as I have explained, she had spent two years in Madagascar studying animal communication, which is the scientific description of how animals talk to one another. We now know that most animals use sound in a much more complex way than we believed. Take bird song, for example. At one time people thought that birds sang because they were happy, say, or because their wife had just laid another egg. We have now discovered that song and the other noises that the animals make have a wide variety of meanings. In the case of bird song, what the bird is really doing is putting up a vocal ‘Private Property’ sign, for other cock birds hearing the song know that this piece of territory has been staked out and claimed by the singing owner. By using the bird’s territorial instincts against itself, as it were, one can find out a lot about numbers and territory. It works like this. Lee, with cunning and patience, obtained a recording of a cocky fody singing his territorial song. She then took this to other areas of the woodland and played it. Immediately, the cock bird in whose territory she was operating would get wild with indignation, sure that his territory was being invaded by another fody, even though he could not see it. He would fly down to within a few feet of Lee and the recorder, uttering his scolding or get-the-hell-out-of-here cry; Lee would walk to and fro, followed by the indignant owner of the territory, who would only give up when she left the edge of his patch of forest. By this means she could work out the extent of the territories and also the numbers of birds. It was very frustrating for the poor fodies who had their homes invaded by invisible rivals, but it did enable us to find out that the population—owing to the rains and the increase in undergrowth—was in far better shape than we had anticipated. The total was over a hundred pairs—not a lot, but significantly higher than it had been. We felt that now there might be some real hope for this lovely little bird’s recovery.
Before we left Rodrigues I took Lee to visit what must surely be the loneliest tree in the world, a lovely hibiscus that is found nowhere else. Once common all over the island, there was now only one specimen, or so I thought. It was a sturdy growth but had been much battered by cyclones, and even now I could see where lots of its tender shoots had been devoured by wandering goats and several of its larger branches had been hacked off, presumably for firewood. At this rate it did not seem to me that the poor hibiscus could survive. But then I discovered a remarkable thing. The tiny local school had asked me to talk to the students and when I went down to do this they proudly showed me (to my astonishment) a sturdy baby hibiscus in a pot. Apparently, realising the rarity of the shrub, the local school had adopted it and taken several cuttings. Some had been sent to Kew Gardens, where, unfortunately, they failed to live; but this one cutting grew and prospered. It was about a foot high when I saw it. The school intends to take more cuttings in the hope that others may thrive and the hibiscus may once again become as common as it had been. Goodness knows, Rodrigues needs every green thing it can save, so we hope the hibiscus will survive under the care of the children.
4. The Treasure Island of Madagascar
The plane flew steadily through the brilliant blue sky while Madagascar, the world’s fourth largest island and probably biologically the world’s most important island, started to unroll thousands of feet below us. Soon the lush rim of the eastern rain forests, a complex mat of greens, reds and purples, gave way to the bare uplands. Here you could see the eroded landscape, great areas wrinkled as a tortoise skin and almost blood-red in colour, with here and there pockets of jade-green grass or small patches of forest in the valley. In the forested rim of the island I knew we should find a breathtaking collection of creatures and plants, for Madagascar, from the zoologist’s and botanist’s point of view, is a treasure-house of unique forms of life. This is the home of the incredible lemurs and the hunting-grounds of strange mongoose-like predators found nowhere else. Here have evolved over forty-five kinds of chameleon, and whereas Africa can boast of one species of baobab tree, Madagascar has nine. There are strange birds, mammals, reptiles, insects and plants which are found nowhere else but in this living museum. How all these creatures came to be here is an amazing story in itself.
For many years zoologists were puzzled by the distribution of animals all over the world in what appeared to be a rather haphazard, sporadic and curious manner. Why, for example, were there elephants in Africa and India but not in Australia? Conversely, why were there kangaroos in Australia but not in Africa? For many years this remained a riddle, but then, comparatively recently, new evidence was found to confirm an idea the zoologists had had, the notion of continental drift.
We know now that since life started to evolve on earth, the earth’s geography has been evolving as well. It is still imperceptibly changing, with the great land masses drifting further apart in some places and closer together in others. Over millions of years the earth has been warped and changed by immense volcanic forces and the pressure of the seas, and the continents, like gigantic granite rafts, floated to and fro over the earth’s cloak of dense but liquid basalt. At one point in history all the southern land masses were huddled together in one great conglomeration called Gondwanaland, and so both plant and animal forms could migrate freely over this great continent. But then it started to split like a jigsaw puzzle, forming southern Asia, South America, Africa and Australia. As they drifted away from each other they carried with them their cargoes of animals and plants, and so these evolved along their own lines without contact with other continental ‘rafts’.
About a hundred million years ago, a great leaf-shaped land mass broke away from east Africa and floated off into the Indian Ocean to become Madagascar. The bulk of its wonderful array of plant and animal life is descended from African forms of this ancient era. But as recently as sixty million years ago the island was still within ‘rafting’ distance of Africa, and so the early forms of monkey—the prosimians—could be carried acro
ss from continental Africa on massive tree trunks uprooted by floods, pushed out into the ocean and tide-propelled to Madagascar’s shore. The rafts carried other living cargoes—seeds, spores, reptile, insects and other forms of mammal. So the wonderful thing about Madagascar is that its creatures go directly back to Gondwana and the time of the earliest primates. For millions of years, unmolested by man, the animal and plant life of Madagascar evolved into a fantastic array of lemurs, showing us alternative evolutionary pathways to those of our earliest African ancestors, which range from the great black-and-white indri, the size of a six-year-old child, to the delicate, big-eyed mouse lemur, three of which would fit into a teacup. There were also other extraordinary beasts but these began to vanish with the coming of man: ten species of large lemur, one that grew to the size of a calf; giant tortoises and twenty-four-foot crocodiles; pigmy hippos lolling in the swamps; and, haunting the forests, the Aepyornis or elephant bird, the heaviest bird ever, clumping through the undergrowth on elephantine feet. Looking like a magnified ostrich standing ten feet high, this fantastic bird laid eggs that could hold two and a half gallons and could have (and probably did) provide an omelette for up to seventy-five people. It was definitely not the sort of egg you find in a supermarket. It is thought that Sindbad’s famous Roc, which could soar away carrying elephants in its claws, was probably based on Aepyornis.