Cara Brook is a Disease Ecologist working in the Andrew Dobson Lab at Princeton. She currently studies the great bats of Madagascar—flying foxes—and the diseases that they carry that could spill over into humans. Capturing and studying wild bats, of course, requires an ability to blend in to Malagasy culture in addition to the environment which, luckily, Cara is quite adept at.
It’s three weeks to the day since my arrival back in Madagascar, and already, the last six months in Princeton, New Jersey seem but a distant memory of a former life. Madagascar has a way of consuming me utterly, such that time is focused on the present more completely than in all other aspects of my life. The months ahead on the Eighth Continent no longer seem daunting, for Madagascar—and my field work—are all there is right now.
I write from the deep and distant Sakalava Menabe, which translates roughly to “The Land of the Long, Big, Red Cat.” Last year, I visited this lonely frontier-land where the waves roll off into the Mozambique Channel and towering baobabs crowd the horizon to organize the work that we’re undertaking now—netting and sampling fruit bats (both Pteropus rufus and Eidolon dupreanum) by the dozen, interviewing hunters, and absorbing the foreignness of this sunstruck, arid landscape.
I feared that returning to Madagascar after a six-month hiatus would spell doom for my foreign language skills, but I need not have worried. My brain seems to have been working subconsciously while preoccupied with life in America, and my Malagasy is back and stronger than ever. There’s still a lot to learn, but for the first time ever, I buy food for our field excursions without the help of my Malagasy collaborator, PhD student Christian Ranaivoson, and I call ahead on my mobile to the taxi-brousse station to make a reservation. Christian smiles proudly and says, “You are coming along so well with your Malagasy!”
I miresaka (chitchat) with Riry, the 4×4 driver we hired to haul our team—plus two canisters of liquid nitrogen, a portable anesthesia machine, and boxes and boxes of camp equipment and lab supplies—down to the Menabe, and he is charmed by my language efforts. “Mitovy zanakako anao,” he tells me before leaving us for his return journey to Tana—You are like a daughter to me—and then he tries to refuse my money. In the end, we compromise. He takes the payment and buys our team—our new undergraduate intern, Yun-Yun Li, Christian, and me—seafood paella in Morondava as a send-off meal before we embark on two weeks of rice and beans. I am touched.
We work with local bat hunters in Mahabo, just inland from Morondava, to collect live Pteropus and Eidolon for our work. Some nights, we go out with them to man the nets under the blooming kapok trees where our flying fox friends come to feed in the moonlight. I pay our hunters 6,000 ariary, or $3 US per bat—a full 1,000 ariary above the going bushmeat rate—though my bats must come alive, unharmed, and be released later. It’s rewarding to engage the local community in our science and an eye-opening experience for us. We haul carrots, potatoes, and rice out into the countryside, and a Malagasy family cooks it for us and shares the meal under the bat nets. Though we’ve hiked only five miles from the town where these goods were purchased, the Malagasy lady tells us she’s never seen a carrot or a potato before. I’ve seen this side of Madagascar before, but I watch Yun-Yun’s eyes widen in amazement. It’s good to be reminded of what it felt like to experience this all for the first time.
During the day, we stay stationed at our little outpost in town, a family-run hotel where we set up a make-shift lab in the courtyard. We process the bats, collecting swab samples, blood samples, hair samples, and, from a subset of our bats, tooth samples to build age-prevalence curves for pathogen infections. My advisor, Andy Dobson, generously donated a shiny new halothane vaporizer plus anesthesia machine to our field project shortly before my departure from Princeton in June, and I’m stunned by its effectiveness and thrilled by its gentleness with our animals.
Fruit bats annually deposit layers of a cartilage-like material called cementum in their teeth—a bit like a tree ring—and so, we can tell their age by extracting their teeth. This data is important for disease transmission models because we can deduce R0, the basic reproduction number for a pathogen, from age-infection prevalence data. Age data is also crucial to understanding population dynamics and building life-history tables for bat conservation efforts. At present, no one really knows how many fruit bats there actually are in Madagascar, though it is rumored that all three species have experienced 20-30% declines in the past fifty years, largely attributed to hunting. By interviewing hunters in different regions and assessing the age distribution of various bat populations, we hope to be able to establish a relationship between hunting pressure and bat demography in Madagascar. And since little in ecology happens in isolation, impacts on demography likely will have impacts on pathogen dynamics, as well.
But I digress. As one who has anesthetized civets, mongooses, deer, and wolves under a variety of different chemical mechanisms, I feel qualified to assert that Andy’s anesthesia machine is wonderful. Our bats are asleep in thirty seconds, the lower left premolar tooth removed cleanly in a few minutes, and after a shot of antibiotic and another of analgesic, they are alert and squabbling again a few minutes later. We feed them sugar water and watch them soar away into the sunset.
In the morning, I jump rope in our courtyard laboratory for exercise, and the little girl next door brings out her own rope to join me. Yun-Yun takes videos of the two of us on her camera, and I smile to think how good it feels to be making so many friends in Madagascar.