Checking In on the Toad of Monteverde
MICHELE NORRIS, host:
This is ALL THINGS CONSIDERED from NPR News. I'm Michele Norris.
Now, another installment from our series Climate Connections with National Geographic. Twenty years ago, scientists were worried about global warming, but they didn't know what to expect. Then in 1999, the journal Nature printed a cover story about the extinction of the golden toad in Costa Rica's Monteverde Cloud Forest. It was one of the first clear indications of the effects of increase in temperature.
NPR's John Burnett visited Monteverde to see what's changed nine years after the groundbreaking report.
JOHN BURNETT: In order to care about what's happening on a remote mountaintop in Central America, you need to know something about Monteverde - green mountain. What an extraordinary place.
At 5,000 feet, Monteverde straddles the continental divide. Rains and cloud mists from the Pacific and the Caribbean bathe the mountain in near-constant moisture, producing a cool, lush, shrouded setting that verifies our dreams of what a cloud forest ought to be.
(Soundbite of birds chirping)
BURNETT: Plants grow on plants that grow on other plants in an orgy of fertility and adaptation. Here, scientists have identified 755 species of trees, 420 types of orchids, 68 kinds of bats, and more than 425 species of birds, including the three-wattled bell-bird, whose unmistakable call was captured on this recording by Andrew Roth(ph).
(Soundbite of bird call)
BURNETT: Monteverde is an ark, and it's in trouble.
Dr. KAREN MASTERS (Field Biologist): Okay. Here are the features of taxa that are probably at risk in Monteverde. Any taxon, any organism that has a narrow climate envelope...
Dr. Karen Masters is a Michigan-born field biologist who has lived and researched here for 20 years. In jeans and a sweater, she stands inside a classroom in the forest lecturing on tropical ecology to a group of U.S. university students. Today's lesson: Climate change is producing more dry days and warmer nights on the mountain. Consequently, certain life zones are expanding.
Dr. MASTERS: The forecast for biological change in Monteverde - well, we know that birds are moving upslope. So obviously, there are some winners in the equation. For instance, keel-billed toucans have expanded their range. That's great if you're a keel-billed toucan. It's not great if you are a Resplendent Quetzal.
(Soundbite of bird call)
BURNETT: That's the sound of a Resplendent Quetzal. In Monteverde, quetzals and toucans now compete for the same hollow trees to nest in. What's worse, toucans think quetzal eggs are yummy.
One of the things that's going on here is something called the escalator effect. At Monteverde, species that already live on the mountaintop - such as the fiery-throated hummingbird - cannot migrate any higher. Now they're endangered. Scientists have observed the same thing happening to butterflies in the mountains of Central Spain, tree possums in Australia, and pikas in the American West. As Karen Masters says, climate change is shuffling the deck.
Dr. MASTERS: All right. So it's going to be slippery and you got to watch your step.
BURNETT: Masters has her own research project just down the slippery slope from the classroom. Her specialty is epiphytes - plants that live on other plants. In a clearing, she's created a an orchid garden with hundreds of miniature orchids mounted on horizontal poles. Her research subject is one of the tiniest orchids in the world, smaller than a blueberry.
Dr. MASTERS: They truly are diminutive and extremely cute.
BURNETT: Though she does not want to reveal too much, since they want to publish their results, Masters and her coauthor have found that the tiny orchids in this narrow life zone are under stress and drying out.
Dr. MASTERS: We're having micro-droughts that can last for two to ten days, and although that doesn't sounds like a lot, for plants that live off of the ground, the plants that live up in the canopy, who depend on wind-borne moisture and nutrients, that can make the difference between life and death.
BURNETT: Since the disappearance of the golden toad 19 years ago, scientists have documented more amphibians vanishing throughout the American tropics. Anyone who's lived in Monteverde for a while has noticed it too.
When nature guide Javier Perez(ph) began giving tours of the cloud forest preserve three years ago, they would normally spot 40 frogs on their loop walk.
Mr. JAVIER PEREZ (Nature Guide, Monteverde Cloud Forest): Today, only three years later, in two hours' walk with the most carefully looking - today it's only two or three frogs in the whole loop.
BURNETT: Unless they're told, visitors wouldn't know anything as wrong. In fact, they may be happier because less rain means the roads and trails are not as muddy. To them, Monteverde still offers an astounding encounter with nature.
Mr. MALCOLM HALL(ph) (Tourist): Of course, we've seen a lot of coati around here. And we saw a sloth.
BURNETT: Malcolm and Betsy Hall(ph) were visiting from New York City.
Ms. BETSY HALL (Tourist): It's so great, and it shows you the difference in what a cloud forest is because you really do see how unique it is compared with anyplace else. Well worth going through.
BURNETT: To biologists who study this mountaintop, the living things that appear to be threatened by the effects of climate change, from orchids to hummingbirds, are deeply troubling. Karen Masters.
Dr. MASTERS: They're all profound. They're all pretty heartbreaking.
BURNETT: Once upon a time, deforestation was the greatest threat to biodiversity in Monteverde. Indeed, to tropics everywhere. With the specter of climate change upon them, biologists now look back and wish their foe were so obvious.
John Burnett, NPR News.
NORRIS: You can hear more Climate Connections stories at our Web site, npr.org/climate. And while you're there, you can get the latest climate change features from National Geographic Magazine.
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