By Jennifer S. Holland Photographs by Joel Sartore
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L42^ 4,- 44 4,. ;4:1 44, 44 44 • BY JENNIFER S. HOLLAND PHOTOGRAPHS BY JOEL SARTORE 138 NATIONAL GEOGRAPHIC • APRIL 2009 SURO STREAM FROG • Hyloscirtus pantostictus At Pontificia Universidad CatOka del Ecuador UP TO 2.5 INCHES • SOUTH AMERICA • ENDANGERED 1 E GRIPS HIS MATE, front legs clasped Egyptians they symbolized life and fertility; tight around her torso. Splayed beneath and for children through the ages they have H him like an open hand, she lies with been a slippery introduction to the natural her egg-heavy belly soaking in the shallow world. To scientists they represent an order that stream. They are harlequin frogs of a rare Ate- has weathered over 300 million years to evolve lopus species, still unnamed and known only in into more than 6,000 singular species, as beauti- a thin wedge of the Andean foothills and adja- ful, diverse—and imperiled—as anything that cent Amazonian lowlands. The female appears walks, or hops, the Earth. freshly painted—a black motif on yellow, her Amphibians are among the groups hardest underside shocking red. She is also dead. hit by todays many strikes against wildlife. As Above this tableau, at the lip of the ravine, a many as half of all species are under threat. bulldozer idles. Road construction here, near the Hundreds are sliding toward extinction, and town of LimOn in southeastern Ecuador, has sent dozens are already lost. The declines are rapid an avalanche of rocks, broken branches, and dirt and widespread, and their causes complex— down the hillside, choking part of the forest-lined even at the ravine near LimOn the bulldozer is stream. Luis Coloma steps gingerly over the loose just one hazard of many. But there are glimmers rocks, inspecting the damage to the waterway. of hope. Rescue efforts now under way will shel- The 47-year-old herpetologist is bespectacled ter some animals until the storm of extinction and compact in a yellow shirt dotted with tiny passes. And, at least in the lab, scientists have embroidered frogs. He hasnt bothered to roll up treated frogs for a fungal disease that is devas- his khaki pants, which are soaked to the knees. tating populations around the world. Poking a stick into the debris, he says, "They have In Quito, Coloma and his colleague Santiago destroyed the house of the frog." Ron have established a captive-breeding facil- Frogs and toads, salamanders and newts, ity for amphibians at the zoological museum wormlike (and little-known) caecilians—these at Pontificia Universidad CatOlica del Ecuador. are the class Amphibia: cold-blooded, creep- They admit its a drop in the pond, offering safe ing, hopping, burrowing creatures of fairy tale, harbor to a select few in hopes of stemming biblical plague, proverb, and witchcraft. Medi- national losses. The facility houses just 16 spe- eval Europe saw frogs as the devil; for ancient cies, although Ecuador is home to more than 470. And thats just whats on the books. Despite Jennifer S. Holland is a senior writer for National heavy deforestation across this country, every Geographic. Joel Sartore is a frequent contributor to year new species are discovered. Colomas lab the magazine, often photographing threatened species. has about 60 recently discovered species still BOREAL TOAD COMMON FIRE SALAMANDER Anaxyrus (Bufo) boreas Salamandra salamandra At the Cheyenne Mountain Zoo, Colorado At the St. Louis Zoo, Missouri UP TO 5 INCHES . WESTERN UNITED STATES . DECLINING UP TO 10 INCHES • EUROPE • DECLINING r. g Scientists in Ecuadors Andes test an Atelopus frog for chytrid fungus (result: positive). The frogs breeding stream was clogged with construction debris. Forest clearing, aridity, and infectious disease are proving a lethal mix for a host of species in the amphibian-rich Southern Hemisphere. b 11 OOPHAGA SYLVATICA PRISTIMANTIS SP. GOLDEN POISON FROG At Pontificia Universidad Catdlica del Ecuador At Reserve Las Gralarias, Ecuador Phyllobates terribilis UP TO 1.5 INCHES • SOUTH AMERICA . DECLINING UP TO 2 INCHES • ECUADOR STATUS UNKNOWN At Rolling Hills Zoo, Salina, Kansas UP TO 2 INCHES • COLOMBIA • ENDANGERED By 2000, teams were grabbing up animals to stash them away— at zoos, at hotels, anywhere space could be carved out. awaiting scientific names—enough to keep ten the LimOn stream. Both animals tested posi- taxonomists hard at work for a decade. tive for chytrid fungus, and the male died soon Coloma and Ron, who have also initiated after the female. land purchases for habitat protection, hope to Chytrid was wiping out amphibians in Costa add room at the captive facility for more than a Rica back in the 1980s, although no one knew hundred species. But the pool of wild animals is it at the time. When frogs started dying in big shrinking fast. Where field scientists once had to numbers in Australia and Central America in watch their step to avoid crushing frogs moving the mid-1990s, scientists discovered the fungus in mass migrations, now counting a dozen feels was to blame. It attacks keratin, a key structural like a victory. "Were becoming paleontologists, protein in an animals skin and mouthparts, per- describing things that are already extinct: Ron haps hampering oxygen exchange and control says. At the Quito lab the evidence is stacked of water and salts in the body. African clawed The protein keratin is the target of chytrid fungus. Frogs have more of it than tadpoles, making them more vulnerable to infection. O Keratin high. Coloma holds up one jar from a cabinet- frogs, exported widely for pregnancy tests ful. Two pale specimens bob in alcohol. "This beginning in the 1930s, may have been the species," he says, his face distorted through the initial carriers of the fungus. "Its amazing we glass, "went extinct in my hands." havent seen even more population crashes, the way we shuffle things all over the world, ITS NO WONDER some view our time on Earth complete with pathogens," notes Ross Alford of as a mass extinction. Biodiversity losses today Queenslands James Cook University. have reached levels not seen since the end of Chytrid is now reported on all continents the Cretaceous period 65 million years ago. where frogs live—in 43 countries and 36 U.S. Yet amphibians were able to hold on through states. It survives at elevations from sea level to past extinction spasms, surviving even when 20,000 feet and kills animals that are aquatic, 95 percent of other animals died out, and land-loving, and those that jump the line. later when the dinosaurs disappeared. If not Locally it may be spread by anything from a then, why now? frogs legs to a birds feathers to a hikers muddy "Todays amphibians have taken not just boots, and it has afflicted at least 200 species. a one-two punch, but a one-two-three-four Gone from the wild are the Costa Rican golden punch. Its death by a thousand cuts," says Uni- toad, the Panamanian golden frog, the Wyoming versity of California, Berkeley, biologist David toad, and the Australian gastric-brooding Wake. Habitat destruction, the introduction of frog, to name a few. Some scientists play down exotic species, commercial exploitation, and the importance of any single factor in over- water pollution are working in concert to deci- all declines. But in a 2007 paper, Australian mate the worlds amphibians. The role of climate researcher Lee Berger and colleagues, who first change is still under debate, but in parts of the laid blame on the fungus, put it this way: "The Andes, scientists have recorded a sharp increase impact of chytridiomycosis on frogs is the most in temperatures over the past 25 years along spectacular loss of vertebrate biodiversity due to with unusual bouts of dryness. disease in recorded history" But a form of fungal infection, chytridio- Its been a time of desperate measures. For mycosis (chytrid for short), often administers example, after Southern Illinois University the coup de grace. It did for the mating pair in researcher Karen Lips and colleagues reported MARIEL FURLONG, NG STAFF. SOURCES: LEE BERGER AND RICK SPEARE, JAMES COOK UNIVERSITY si- fungus-related declines in Costa Rica and venture aimed at keeping at least 500 species on Panama in the late 1990s, they began mapping in captivity for reintroduction when—if—the chytrids path and predicting its victims. By crisis is resolved. But the task is immense and sta 2000, teams were grabbing up animals from the expensive, and theres no guarantee how many ew most vulnerable species to stash them away—at healthy wild places will be left for amphibians big zoos, at hotels, anywhere temporary space could to recolonize. in be carved out for stacks of aquariums. Sick ;US frogs were treated and quarantined. Many were THE TROPICS, where conditions foster high tral exported (with much political wrangling) to amphibian biodiversity, have seen the most per- U.S. zoos, while a Panamanian facility was built dramatic declines. But more temperate climates trol to house nearly a thousand animals. So began havent been spared. Consider the cold, upper ved the Amphibian Ark, a growing international reaches of the Sierra Nevada of California. Here, NORTH • AMERICA • EUROPE ests Chytrid on the March ASIA the Global data reveal the alarming reach . of amphibian chytridiomycosis, first we AFRICA reported in the wild in Australia, but Area w • hes, likely originating in Africa. Enlarged trld, .1, SOUTH -d of AMERICA • jr AUSTRALIA ents . Igr 4 • U.S. • Chytrid sampling sites as of 2008. el to Surveys in Asia are under way. 4.•`• NICARAGUA 0 Positive Latic, O Negative line. )m a 1987 COSTA o .- uddy .• tcies. RICA .•.0 Caribbean Aden do 1993 ming Sea 2006 ding Ilk1996 PANAMA 2004 C,AtIAL own 2002 over- • Panama alian In Central America (above) the City Cope 3 first fungus has moved like a wave—spreading up to 27 miles PANAMA "The a year.