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fieldnotes
Endangered
Species Gazing into the remote oyamel forest of central Mexico, it's difficult to imagine that monarchs could be in trouble. The trunks and branches of tall firs, which stretch like pillar candles from the loamy green understory, drip with tightly packed clusters of the butterflies. As the midday sun warms their tiny bodies, they dip and swirl against the March sky like thousands of fiery, falling leaves. But to the experienced eye, here at Sierra Chincua and all through the 139,000-acre Monarch Butterfly Biosphere Reserve, the forest is unusually empty. At five of the 12 sites where the monarchs regularly hibernate, none could be found this year; in the remaining seven, the area covered by these delicate creatures was likely the smallest since 1975, when the first overwintering site was discovered. The monarchs here have made an impressive trek from their breeding grounds, east of the Rocky Mountains in the United States and Canada. There the heavy application of chemicals—particularly on crops engineered to be herbicide-resistant—wipes out milkweed, the sole food source of monarch larvae. When the adult butterflies finally reach Mexico in the fall, they find 1,375 miles of access roads that have opened the forest to illegal loggers. “This wonderful butterfly is under assault,” says Lincoln Brower, a biologist from Sweet Briar College in Virginia, who has studied monarchs since 1954. “If logging doesn't stop, it won't have a chance in hell.” Aerial photography and remote sensing reveal that between 1971 and 1999, 44 percent of high-quality oyamel forest cover—which creates the precise microclimate monarchs need to survive the winter—had become fragmented. And the rate of deforestation is accelerating. Manmade gaps in the forest expose butterflies to increased predation from grosbeaks and other birds, and to precipitation, which climate-change models indicate will triple at the overwintering sites in the next 50 years. Monarchs can't withstand freezing temperatures when they're wet, so severe winter storms, such as the one that caused 80 percent monarch mortality in 2002, can dramatically reduce the population in one fell swoop. This past spring, however, 11 leading monarch scientists, led by Brower, released a statement warning that humans are playing an ongoing game of “butterfly roulette, gambling that breeding success will allow the monarch population to recover from the combined effects of natural and anthropogenic mortality.” Even if monarchs survive, their spectacular migration may not. The 2,000-mile journey keeps the population healthy by weeding out the weak, according to a recent study from Georgia's Emory University. If the migration collapses because of climate change or habitat loss, the butterflies may become remnant, year-round residents far more vulnerable to parasitism. “The migration is an incredible phenomenon, both beautiful and little understood,” says Carlos Galindo-Leal, forest program coordinator for the World Wildlife Fund-Mexico, which surveyed the overwintering sites. Scientists were surprised to discover that Sierra Chincua—traditionally the second largest site in the butterfly reserve—has shrunk the most since last year, from seven acres of butterflies to less than an acre. “Monarch populations have rebounded in the past,” Galindo-Leal says, “but it all depends on a combination of factors. There is little we can do about environmental factors but a lot we can do about the human ones.” ———By Jennifer Bogo
When late spring warms the air over southeastern Nebraska, volunteers Ernie Rousek and Tim Knott of Lincoln's Wachiska Audubon Society scour hayfields and pastures along back roads, alert for telltale flashes of color that signal “prairie!” “Prairie flowers come on strong here in mid-May through early July,” explains Knott, who has volunteered at Wachiska Audubon since 1976. “We may spot the creamy-yellow blossoms of plains wild indigo, the bright yellows of prairie ragwort, and the white or pinkish prairie phlox. They're indicator species, telling us the land hasn't been plowed.” Such fields become targets of these two inexhaustible hunters of the last remnants of this nation's tallgrass prairie. (Only about 1 percent of the 400,000 square miles of tallgrass prairie that once blanketed much of central North America remains.) They follow up with visits to the landowners. Some, especially older farmers proud of their prairie patches, become preservation converts. Since 1994 Rousek and Knott have helped preserve 22 prairie plots ranging in size from 5 to 43 acres. They secured 17 of these properties by conservation easements, through which they may offer advice on maintaining the land; another was donated in a will; and the rest were purchased with funds from the Nebraska Environmental Trust. Rousek and Knott's goal is to secure at least one prime specimen in each of the region's 17 counties. “While about 20 active chapter members work with landowners and state and county officials to save prairie, Ernie and Tim carry the brunt of the load,” says Arlys Reitan, a colleague at Wachiska Audubon. “They are local heroes.” Their trophy restoration, however, remains Nine-Mile Prairie. Several generations of agronomy students at the University of Nebraska had used this plot as an outdoor lab. (“Nine-Mile” refers to its location, five miles west and four miles north of the center of Lincoln.) But plowing and overgrazing eventually degraded the site. “I grew up in Nebraska surrounded by prairie, and I wanted to reclaim a historic area like Nine-Mile,” says Rousek, a professional soil scientist before his retirement. “By state law the Lincoln Airport Authority, then its owner, couldn't sell below market value. So our chapter leased it while we lobbied the legislature. In 1982, when the University of Nebraska Foundation raised $137,000 to buy the remaining 230 acres, I went on the foundation's prairie management committee. We stopped haying and grazing but burned one-third of the land each year. As we suppressed the alien plants, the true prairie returned.” University students still carry out research at Nine-Mile Prairie. Schoolchildren come for tours. Upland sandpipers and other grassland birds, at low levels since World War II, are back on the land in force, whistling across their new home. —By Frank Graham Jr.
Interview
John R. Hamilton, U.S. Ambassador to Guatemala, has watched birds wherever his 35-year diplomatic career has taken him. In December 2002, after serving throughout Latin America and parts of Europe, Hamilton was posted to Guatemala, where he will continue to spend his free time pursuing the country's 700 species of birds until his retirement in July. Audubon recently asked him about pursuing his favorite pastime in one of the world's best birding locations. Question: You've worked in quite a few Latin American countries. How does Guatemala rank in terms of birding? Hamilton: It's certainly up there with Costa Rica. Both Costa Rica and Guatemala have a variety of habitats and ecosystems; Guatemala actually has more. And all this in an area the size of Ohio. I never go anywhere without taking my binoculars. Guatemala City is in a valley that's just laced with ravines that are quite deep, and they're teeming with birds. I've identified 49 species right here in my backyard. That includes three orioles and four species of tanagers. Q: What are your favorites? A: It's hard not to start off with the resplendent quetzal, but I like the gray silky-flycatcher. We have two pairs of them nesting in our backyard. Q: Have you been a birder for a long time? A: Since my midtwenties. My father was a lifelong birdwatcher, but he loved it so much he dragged it down the throats of his five kids. And we all resisted. But then I joined the diplomatic service, and I was assigned to Spain. I saw a bee-eater, and I got hooked. Nothing I did pleased my father more than when I became a convert. Q: Do you particularly enjoy the company of birdwatchers? A: Birdwatchers tend to be educated people who are also active in communities and who are interested in public affairs and, certainly, the ones that go to Guatemala or to other places are to a degree internationalists. That is the sector of American society I am really delighted to see go abroad. They are good representatives of the U.S. Q: Does this make cooperation between the two countries particularly important for neotropical migrants, many of which come to Guatemala from the United States? A: It does. I hope to see more cooperation. There is a program, a very interesting one, designed to support the habitat of the golden-winged warbler, which breeds in central and eastern North America. It migrates through Mexico and down through the Guatemalan highlands. From an ambassadorial standpoint I just love to see linkages like that protecting the environment. —By Jesse Greenspan Imagine a multiyear drought that blisters the landscape. Grasslands are overgrazed and farm fields overplowed. Cattle and crops wilt in the relentless heat. Winds blow topsoil off the land, resulting in “black blizzards.” This is no fictional scenario; it's how the Dust Bowl played out across 27 states in the 1930s. Scientists and farmers were completely caught off guard by the devastating chain of events. Today there is a new federally funded project under way to foretell climate phenomena and environmental conditions before they develop into Dust Bowl–like tragedies. The National Ecological Observatory Network (NEON) will establish a nationwide spider's web of technologically advanced field research stations—all cyber-networked to share data and allow unprecedented, countrywide observations. Thousands of state-of-the-art field sensors will constantly measure water, air, vegetation, and wildlife activity from coast- to-coast. The aim of the project, which is sponsored by the National Science Foundation and the American Institute of Biological Sciences, is to study seemingly disconnected environmental problems and piece together emerging trends on a massive scale. “We want to be able to forecast problems before they occur, so people can adjust to them,” explains NEON scientist Jim MacMahon. The high-tech infrastructure, including satellites, will be put in place over a 30-year period, says NEON program officer Elizabeth Blood. It will eventually help predict the effects of climate change, invasive species, and the spread of new infectious diseases like West Nile virus in much the same way that meteorologists currently forecast the weather. With invasive species, for example, airborne sensors would be able to detect the form and structure of a plant and would know the instant an invasive expanded its range. Scientists would then track the spread of the species to develop an appropriate method of control or eradication. Similar ecological prognosticating is currently used by the National Oceanic and Atmospheric Administration to measure fish stocks and water quality in the Gulf of Mexico. With a goal of making NEON as well- known as NASA, its designers are drawing up a massive public outreach and education campaign, which will include developing enviro-games (NEONtendo), cyber-linking NEON to schools, and establishing community learning centers across the country. For additional information, log on to www.neoninc.org.—By Aaron Teasdale
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