| The Magazine of the CALIFORNIA ACADEMY OF SCIENCES |
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| Feature No Time for Lemurs
As the Air Madagascar plane crosses the coastline of its homeland, the on-board TV screens come to life to show a men's chorus singing sentimental folksongs. There are few Malagasy in the audience, but I see one or two passengers briefly wipe their eyes. Below us an expansive plume of red silt stretching far out into the Mozambique Channel overshadows the coastal features. It marks the mouth of the Betsiboka, one of the country's major rivers. We follow the course of the river south toward the capital, Antananarivo, and the international airport. The water never loses its pomegranate tone, and, from the ruddy scars that mark the steep sides of the tributaries feeding the river, it is easy to see why. These scars, clearly recent, are signs of a landscape in transition. It's hard to imagine that this central high plateau was ever forested. There is little sign of any vegetation beyond a coarse grassland, and nothing to suggest that this is a land famous for its unique wildlife. There is a legend of a conflagration that destroyed vast areas of forest hundreds of years ago. But what isn't legendary is the common practice of what the Malagasy call tavy–slash-and-burn agriculture. As with most tropical rainforests, the soil is severely leached even while the protective canopy is in place. What little nutriment that does exist in the ashes of the burned trees is exhausted after a year or two's cultivation. Today, farmers light their fires higher and higher on steeper ravines, so that much of the exposed topsoil soon slips away. Some soil finds a home in the cultivated valleys: the rest ends up in the ocean. Most of the valley floors and gentler slopes were long ago covered by a network of irrigated rice terraces which, from the air, shimmer in vivid chartreuse. The scene is more reminiscent of Asia than Africa, and reflects the origins of the first inhabitants. The original Madagascans came to this island not from the adjacent continent, some 250 miles to the west (and populated with modern humans for over 100,000 years), but from southeast Asia, probably from what is now Indonesia. Some have argued they came directly, but more likely they leapfrogged around the coast of the Indian Ocean until, only about 2,000 years ago, they discovered this large, fertile, and unpopulated land.
Madagascar is a world unto itself. When the large southern continent of Gondwanaland began breaking up, about 150 million years ago judging from the age of the Mozambique Channel seabed, the split separating the island and the African continent came quite early in the process. Only later did Madagascar part company with what is now India. For some 100 million years the fauna and flora of this island have evolved almost utterly independently of the rest of the world. Estimates suggest that 80 percent of the plants and over 90 percent of the insects are found nowhere else, which is what makes the country a magnet for biologists. The larger animals have long gone, easy prey to early humans. Here once lived, Aepyornis, the flightless elephant bird standing ten feet tall and perhaps the largest bird that ever lived, the ground-dwelling, gorilla-sized lemur, Megaladapis, and the pygmy hippo. Today there are few wild mammals, perhaps no more than 100 species, and the largest, a lemur, the diademed sifaka, and the predatory cat-like fossa, weigh less than 20 pounds. All the mammals, except those brought by people, and some species of bat, are endemic. It is the threat to Madagascar's native fauna and flora brought about by the country's burgeoning population–currently 14 million–the practice of tavy together with the country's limited economic resources that has created the urgency for biological exploration. The Malagasy government, prompted by a report by the World Wide Fund for Nature, and supported by international aid organizations, has begun to conserve and, in places, try to restore the remaining natural habitat, particularly the rainforests. Prominent among the organizations committed to preserving the wildlife is the Institute for the Conservation of Tropical Environments (ICTE), based in Stony Brook, New York. The institute was critical in providing the impetus and finding the funds necessary to establish Ranomafana National Park in 1991. Spurred by reports of species diversity and, even more, by the high endemism, it is to Ranomafana, in the country's eastern rainforest that we have set our course. I am here to dog the footsteps of a crew of entomologists from the California Academy of Sciences. They have come on an expedition, funded in part by the Oracle Foundation, to inventory the park's arthropods: spiders and insects. The specific focus of the Academy's team is to study the spiders, carabid beetles, Neuroptera–lacewings and ant-lions–and Megaloptera–alder-flies and fish flies. It is appropriate that a computer company should offer its assistance. The task of compiling a matrix which will compare the many critical, defining characteristics among the hundreds of thousands of arthropod species is beyond the grasp of mere humans. Nowadays, in every country–and the United States is among the most exacting–the act of collecting animals or plants, alive or dead, is corralled by bureaucracy. Permits. One to enter a country, another to do research, a third to collect, and, hardest of all, a last to export, for, when foreigners are involved, the bar is raised. There are ample reasons why. Developing nations recognize that their biota is an economic resource, and one that will become more and more valuable. And many of their endemic species are likely to soon become endangered, if they aren't already. If animals and plants are to leave their native shores, it better be to a good home and for a good reason. Madagascar is no exception to the permit rule. We are, after all, expecting to leave the country with up to 15,000 specimens. Nevertheless, when we meet with National Coordinator Benjamin Andriamihaja, ICTE's main man in Madagascar, the day after our arrival, he assures us that all the permits have been taken care of. "There is no reason," he says, "why you can't leave tomorrow." Zoologist Gerald Durrell accurately described Andriamihaja in his book, The Aye-aye and I, as "Mr. Fixit." It turns out there was one permit still outstanding, the one for alcohol. Many of the specimens, those with "soft parts," need to be preserved in a liquid that will prevent decay. Of all the various alternatives, ethanol–ethyl alcohol–is the most efficient, easy to work with, and most easily obtainable. Except on a Friday afternoon in Tana. (Madagascar's towns all have long names, so most, like Antananarivo, are routinely abbreviated.) First, the application requires a justice's approval. The first judge told us to come back on Monday, but a trip across town found someone more sympathetic. Then comes the harder task of finding ethyl alcohol in sufficient quantities–20 liters. Instead we had to make do with rubbing alcohol, the far more lethal methyl alcohol, and four liters of Malagasy rum. Although most of the journey is on the country's main north-south road, the eleven-hour ride south to Ranomafana deserves to be a PBS special. As we leave the city, the road is a river of people. It is like a Breugal painting, as though the whole population work, play, and live beside the road, or on it. Everyone is individually occupied–washing clothes, fishing, planting rice in one field, harvesting it in another, and hawking between the vehicles everything from fruit to bathroom scales. The road is where two centuries intertwine. Beside the 60-foot Mercedes Benz tractor trailers and utility vehicles are rickety carts pulled by hand, lean zebu cattle and even leaner horses, rickshaws ("pousse-pousse," locally), ancient vehicles, every one exuding smothering black diesel smoke, and a thousand pedestrians, many, especially the women, balancing baskets and boxes on their heads. Of course, there are no sidewalks and even the major roads are only wide enough for two cars to pass. How it all gets through unscathed is a mystery, and often it doesn't. Accidents are not uncommon. We emerge periodically, untangle ourselves from a morass of limbs and luggage to eat, stretch, and watch our Malagasy companions haggle for fruit and vegetables from roadside venders. The food is all displayed precariously: potatoes, apples, persimmons in carefully balanced spires. Wherever we stop, we are surrounded by wide-eyed children. Half the population of Madagascar is under 16 and the life expectancy of males is only 52–close to the average age of this strange band of bearded biologists. The curiosity is mutual. Eventually, we leave the maintained road, and turn east along a 15-mile switchback to be tossed about like a rowboat in ten-foot seas. At the edge of the rainforest, we are greeted, appropriately, by a torrential downpour. By the time we reach the entrance to the park some two hours later, we disembark in pitch darkness and, with our raingear inaccessible, hike, slip, and slide down to the research station, along a trail illuminated by lightning. Next morning there is not a cloud in the sky. It is a day to recuperate and dry out, not only last night's clothes but most of the stuff still packed in the luggage. Fortunately, the tent sites are well-made and dry beneath oversized tarpaulins. It's not difficult to find the park's celebrities. Our first lemurs appear in the branches above the tents before breakfast. They are golden bamboo lemurs (Hapalemur aureus), a species which was only discovered by science in 1986 and is not thought to exist anywhere else. It was the discovery of H. aureus, by primatologists Bernhard Meier and Patricia Wright, founder and head of ICTE, that led, after considerable fund-raising and assurances to the local population that the benefits would outweigh any inconvenience, to the creation of this national park. The lemurs attract their own band of year-round, round-the-clock researchers, most of them operating under Wright's direct guidance. Besides researchers from America and Europe, a platoon of Malagasy guides monitor the lemurs' movements, socialization, and, with the help of droppings from on high, diet and internal parasites. But the entomologists have not come here to look at lemurs. Although Griswold has suggested everyone take a day off to acclimatize and reconnoiter, it is hard to hold an enthusiastic entomologist down–and I have yet to meet an entomologist who is not enthusiastic, especially in a forest teeming with undiscovered treasures. The Madagascar rainforest is uniquely benign at this time of year. No large mammals, no crocodiles, poisonous snakes, or vicious insects, no armed flora waiting to stab and scratch. There are only two potential adversaries–mosquitoes and leeches. We didn't see, hear, or feel many mosquitoes. They don't come out much in the daytime anyway, and everyone was wrapped in repellent. Leeches, however, were taken seriously, though they're quite harmless and only about an inch long with the diameter of a pencil lead–before they dine, that is. There are two approaches to confronting leeches. One is to be blase, and wear shorts and sandals. The leeches find you, but you can find them equally easily. That's the Malagasy approach. That, and a pouch of tobacco powder to sprinkle on the transgressors so they drop off. The alternative approach is to attempt a defense with long trousers, wool socks, and boots. If it works, fine; if it doesn't...you find out later. There was one notable occasion where that second approach clearly didn't work. The researcher lifted his trouser leg after a morning in the forest to reveal 30 bloated monsters gorging at the top of his boot. The scientists will spend almost every day of the next five weeks, from seven in the morning till nine at night, midnight if the collecting is good, scratching trees, turning over rocks and searching through the detritus of the forest for their elusive prey. At one point Griswold, flat on his back for two days in his tent with severe cramps and a temperature of 102o F from one of those microscopic bugs the tropics are infamous for, still could not resist the occasional capture on his necessary excursions. Charles Griswold's dedication has helped establish him as one of the world's leading experts on spiders. Holder of the Schlinger Chair in Arachnida at the Academy, Griswold has been instrumental in discerning some critical clades–evolutionary relationships–of arachnid families. This part of the world is particularly interesting to him, as one of his specialties is the montane spiders of Africa. He is on the lookout for four particular families: lace-web builders, or Phyxelididae, trapdoor spiders, or Migidae, sheet-web building spiders or Cyatholipidae, and burrowing spiders, or Udubidae. Each entomologist has his preferred collecting technique. Griswold is a sifter of litter. He carries, folded up in a backpack, an umbrella and a canvas bag that has wire netting across its base. Arriving at a promising spot with lots of leaf litter, Griswold grabs a handful and quickly pushes it into the bag, then shakes the bag over the umbrella, and waits for spider nuggets to fall. To capture a fallen spider, which might be no more than one or two millimeters long, requires a "pooter," a contraption he has wound around his neck and which looks something between a stethoscope and the Caterpillar's hookah in Alice in Wonderland. At the sight of the prey scurrying to the edge of the umbrella, Griswold puts one end of the pooter in his mouth and sucks. The scuttling spider disappears, to reappear a moment later as Griswold blows it into a vial. He will study it later; right now there's another victim to intercept. Griswold can spend most of the day in a single spot. There could be a hundred spiders of a dozen different species all within an arm's length. But most will need to be coaxed from hiding. Even the webs are not always obvious. Nearby, Darrell Ubick, Griswold's assistant, is contemplating an assortment of epiphytes growing within a buttress of one of the few large trees. Within their folds glisten the threads of a sheet-web. Ubick removes a "puffer" from his vest. A puffer is something like a turkey-baster with its rubber base half-filled with corn starch. A few squeezes of the ball and the gossamer web materializes white as fine snow, revealing by its shape the location of the builder. The suction tube is engaged and another vial is occupied. Ubick wears a safari vest that seems to hold a limitless supply of vials. Their tops are color-coded: green, for spiders found in the trees, brown for those discovered on the ground, and black for those captured at night. Ubick discovered his affinity for spiders fresh out of high school at an Arizona field station. It took about 15 years to turn his avocation into a career. He is now a curatorial assistant at the Academy. He slips out a magnifying glass and studies his latest addition. Only adult animals are collected. Although, unlike insects, immature spiders look pretty much like their parents, it is not until that final molt, the last instar, that they emerge in their adult skeleton with their tell-tale genitals. Without the genitals, there is no way to accurately compare this find with the descriptions of other spiders. "A juvenile," Ubick sighs, but pockets it anyway, hoping it might mature in the month before he leaves. Meanwhile, David Kavanaugh, tickler of trees, is using a tool like a hand garden fork, its prongs bent at 90 degrees, to scratch the trunk of a ficus tree in ardent search of his favorite quarry. Carabid beetles are generally thought of as ground-dwelling creatures, using their strong legs to push through the leaf litter and their speed to overtake their prey. But here, Kavanaugh has found that they have moved up into the trees, perhaps outcompeted by ants on the ground. In Ranomafana they seem to prefer the recesses of tree bark, and the clumps of dead leaves caught in the branches. They need to be unmasked swiftly and deftly if they are not going to crawl even further into the crevices. Kavanaugh catches the detritus, the moss, and lichen on his unfolded platform. A cockroach–not one of Madagascar's hissing species–scurries for safety unheeded. An interrupted ant patrol is ignored, but a lone longhorn wood-boring beetle gives its life for science. Kavanaugh had planned on becoming a medical doctor, but he began collecting carabid beetles on a trip with entomologist and Academy Fellow Terry Erwin and has never stopped. He stuck with medical studies a while longer, but his penchant for finding new species proved overwhelming. He had found a career "that combined my two favorite activities; mountaineering and insect collecting." Well over 90 percent of the estimated 20,000 beetle species in Madagascar are endemic. Moreover, many of them are thought to be relicts–Gondwanaland fauna which have evolved little over the last 100 million years, so they still resemble ancestors to species found elsewhere in the world, and throw light on the branching of the evolutionary tree. Elsewhere in the forest, Norman Penny, armed with an oversized sweep net, is in search of other prey–not just any insects but delicate lacewings and ant-lions. Penny, Senior Collections Manager at the Academy, set his sites on an entomological life while still in grade school. Impressed with the fragility and beauty of the Neuroptera, he settled on his unusual specialty 30 years ago in Brazil. Penny calls himself "a gleaner of leaves." He strolls slowly through the forest, swinging his net at patches of foliage. With each swing he disturbs a score of bouncing leafhoppers, but he's had his fill of them, and they go unmolested. Only the sight of the tell-tale flight of a dusky lacewing will energize his net. A swing, a quick twist of the handle, and the catch is landed. Penny puts head and shoulder into the opening to block any chance of escape and reaches deep inside to claim his prize. Few are keepers.
It must be quite a shock for the insects in a land empty of electricity to discover this eerie beacon lighting up the woods. The sheet was soon aswarm in silhouettes. The most conspicuous visitors were the hundreds of moths: colorfully striped moths that looked like the flags of nations, moths that resembled geometrical puzzles, one utterly convincing as a fallen leaf, and still others with wings that appeared delicately embroidered. No two, it seemed, were the same. It's a pity no one was collecting moths. Penny stood there unimpressed, waiting, vial in hand, for a neuropteran to settle. At the bottom of the vial are a few drops of nail polish remover, not enough to dampen delicate wings but sufficient to produce a mortal vapor. In the lab, scientists would use ethyl acetate, but airlines discourage the transportation of lethal chemicals. In the field, nail polish remover works fine.
Nighttime proves the best time to collect udubid spiders. Ubick, accompanied by two Malagasy students, Samuelson Randrianarisoa and Marie Jeanne Raherilalao, all become adept at discovering their burrows, small cracks in the ground or the clay walls of steep ravines. One species likes to line the entry with silk, another builds a turret of silk above its cave. By the end of the trip the spider team has discovered eight udubid species, some previously undescribed, and a rare and undescribed migid, a trapdoor spider. For three members of the group, the next day is Larium day. Larium, mefloquine hydrochloride, is the prophylacxis of choice against malaria because in parts of Africa, at least, the other drugs can't be relied on. The Larium pill is taken before, during, and for three weeks after the stay. Malaria is endemic here and we are given a vivid picture of its effects as, within the first two weeks, three of the Malagasy employees at the park have short, painful relapses, while Randrianarisoa is kept to a makeshift bed for a week, hardly able to move. It is a convincing argument in favor of taking our medicine, and some of us need convincing. Larium day looms like a prospective root canal. Anxiety, paranoia, and depression have all been reported by people who take it over a long period. Sometimes the effect comes sooner. Otherwise easygoing, Kavanaugh recalls the heart palpitations after he took his first dose, and the dreadful sense of foreboding that accompanied him the next morning. Larium's specialty seems to be vivid, scary dreams. After his first pill in Ranomafana, Kavanaugh went to sleep to find his whole house had been rearranged and all the furniture that his parents and in-laws had discarded over decades was stockpiled in his office. My Larium days passed uneventfully, although I do recall one night when someone gave me the head of a lemur. It had no fur on it, but was still alive. I tried to find someone to give it to, but all the policemen I approached turned out to be doormen from local hotels who were lining the route that some V.I.P. was about to travel. I tried the railway station, but wound up in the freight department. Finally, I found the passenger platforms, but the stairs which seemed to lead to offices brought me to the top of a double-decker bus.
Just as the light trap and the Malaise traps require a site hard to find in a crowded jungle–an open clearing–so, in this forest, the pit traps are demanding, too. They require level land. If Ranomafana had been flat, the trees would have been burned down decades ago. But a couple of miles of ascents and descents (in the one-hundred percent humidity) and we reach the bed of a stream and what passes for a plain. The pit traps, like the Malaise traps, will stay up for the duration. The cabin where we spent our first bedraggled night has been transformed into a field station: a microscope set up for some preliminary identification, and hundreds of vials unpacked, many already half-filled with alcohol. The smell of cheap rum pervades the room. On one table Schweikert is painstakingly pinning the insects–flies, wasps, beetles–into what looks like a large cigar box. If the insect is more than about five millimeters long, the pin goes adroitly through the thorax. Smaller specimens are glued to a tab. Each insect gets a label, the date and location of its discovery, attached in minute, yet quite readable handwriting. A week after our arrival we are joined by two Fellows of the Academy, Evert Schlinger, retired professor of entomology at the University of California at Berkeley, and Michael Irwin, professor of entomology at the University of Illinois, and one of Schlinger's ex-students. They descend on us like wolves on the fold, emerging from the truck already dressed in kepi hats, boots, the mandatory multi-pocketed vests and carrying sweep nets. Irwin takes a swipe at a traveler's palm, and inspects his first catch of the day. Although Irwin makes his living researching the insect pests of America's soy fields, his first love is the study of fast-moving stilleto flies, whose predatory larvae swim through sand like sharks in the sea, snapping up the soft-bodied larvae of other species. Irwin and Schlinger are only in the country for two weeks and expect to visit sites throughout the south. To maximize their time they have coopted the use of a troop of Malaise traps. And not just the six-foot variety, some of them are 20 feet wide with death traps at either end. Their modus operandi is to traverse a trail–flies, too, prefer trails to dodging tree trunks–until they find an open clearing. Flies like the sun. Across the trail goes the net, with just enough space for people and understanding zebu to get around. Schlinger is the man responsible not only for creating Griswold's academic position but also for inspiring Griswold's, and Irwin's, passion for entomology. He, in turn, was inspired half a century ago on a trip to Africa with the Academy's curator emeritus, Edward Ross who, at 83 years old, still comes to the office every day when he isn't traveling in South America. Entomologists, as a whole, are among the most dedicated of scientists. They never seem willing to retire and hang up their nets. Work and play are all the same.
It is not just the insects that are out. Schweikert nets a passing boa–for photography only–and we discover animals watching us from the recesses of the forest, their eyes reflected in the beam of the headlights strapped on our brows. First a nocturnal striped civet, Fossa fossana, peers at us as we finish dinner, its long pointed nose smelling the chicken. Later, at the limit of the flashlight's beam, I see two pairs of round orange circles glowing from deep within the black jungle. They seem to symbolize the uniqueness of Madagascar's wildlife and all the unexplored mysteries of its forest. Kavanaugh comes over. His headlight, fed by a battery power-pack, is far stronger. He follows my gaze and the four burning rings vanish. Two mouse lemurs, ideally named, scurry away along a vine back into darkness and safety. But the mongooses, snakes, and lemurs do not distract the entomologists from their mission. "We're here to add to that big database and lending library which we call our collection," says Griswold. "We are like medieval scholars, beholden to studying the work of our predecessors. And some of the people who will one day be most interested in what we find are not even born yet. They will be studying the specimens we gather long after we are gone."
Keith K. Howell is the editor of California Wild. |
Fall 1998
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