Climate change may alter amphibian evolution

Tadpole egg clutch

Frogs that are adapting to climate change by laying eggs both in water and on land may be better equipped to handle changing weather patterns. (Photo courtesy of STRI)

Most of the more than 6,000 species of frogs in the world lay their eggs in water. But many tropical frogs lay their eggs out of water. This behavior protects the eggs from aquatic predators, such as fish and tadpoles, but also increases their risk of drying out. Justin Touchon, post-doctoral fellow at the Smithsonian Tropical Research Institute, discovered that climate change in Panama may be altering frogs’ course of evolution.

By analyzing long-term rainfall data collected by the Panama Canal Authority, Touchon discovered that rainfall patterns are changing, just as climate change models predict.

“Over the past four decades, rainfall has become more sporadic during the wet season,” said Touchon. “The number of rainy days decreased and the number of gaps between storms increased.”

The eggs of the pantless treefrog, Dendropsophus ebraccatus, are extremely susceptible to drying. The embryos die within a day when there is no rain. Heavy rains trigger breeding, so as storms become sporadic, the chance of rain within a day of being laid decrease, and so does egg survival.

As weather patterns have changed, the advantage of laying eggs out of water has decreased, not only for pantless treefrogs but potentially for many species. “Pantless treefrogs can switch between laying eggs in water or on leaves, so they may weather the changes we are seeing in rainfall better than other species that have lost the ability to lay eggs in water,” said Touchon. “Being flexible in where they put their eggs gives them more options, and allows them to make decisions in a given habitat, which will increase the survival of their offspring.”

The Smithsonian Tropical Research Institute, headquartered in Panama City, Panama, is a unit of the Smithsonian Institution. The Institute furthers the understanding of tropical nature and its importance to human welfare, trains students to conduct research in the tropics and promotes conservation by increasing public awareness of the beauty and importance of tropical ecosystems. Website:

Beth King, Smithsonian Tropical Research Institute

Press release: Smithsonian Scientists Find Deadly Amphibian Disease in the Last Disease-free Region of Central America

Toad Mountain harlequin frog (Atelopus certus)

The Panama Amphibian Rescue and Conservation Project has established an assurance colony for two species endemic to the Darien, including the Toad Mountain harlequin frog (Atelopus certus), shown here. (Brian Gratwicke, Smithsonian Conservation Biology Institute)

Smithsonian scientists have confirmed that chytridiomycosis, a rapidly spreading amphibian disease, has reached a site near Panama’s Darien region. This was the last area in the entire mountainous neotropics to be free of the disease. This is troubling news for the Panama Amphibian Rescue and Conservation Project, a consortium of nine U.S. and Panamanian institutions that aims to rescue 20 species of frogs in imminent danger of extinction.

Chytridiomycosis has been linked to dramatic population declines or even extinctions of amphibian species worldwide. Within five months of arriving at El Cope in western Panama, chytridiomychosis extirpated 50 percent of the frog species and 80 percent of individuals.

“We would like to save all of the species in the Darien, but there isn’t time to do that now,” said Brian Gratwicke, biologist at the Smithsonian Conservation Biology Institute and international coordinator for the Panama Amphibian Rescue and Conservation Project. “Our project is one of a few to take an active stance against the probable extinction of these species. We have already succeeded in breeding three species in captivity. Time may be running out, but we are looking for more resources to take advantage of the time that remains.”

The Darien National Park is a World Heritage site and represents one of Central America’s largest remaining wilderness areas. In 2007, Doug Woodhams, a research associate at the Smithsonian Tropical Research Institute, tested 49 frogs at a site bordering the Darien. At that time, none tested positive for the disease. In January 2010, however, Woodhams found that 2 percent of the 93 frogs he tested were infected.

“Finding chytridiomycosis on frogs at a site bordering the Darien happened much sooner than anyone predicted,” Woodhams said. “The unrelenting and extremely fast-paced spread of this fungus is alarming.”

The Panama Amphibian Rescue and Conservation Project has already established captive assurance colonies in Panama of two priority species endemic to the Darien—the Pirre harlequin frog (Atelopus glyphus) and the Toad Mountain harlequin frog (A. certus). In addition, the Smithsonian’s National Zoo maintains an active breeding program for the Panamanian golden frog, which is Panama’s national animal. The Panamanian golden frog is critically endangered, according to the International Union for Conservation of Nature, and researchers have not seen them in the wild since 2008.

Bd infection

Chytridiomycosis is a rapidly spreading amphibian disease that attacks the skin cells of amphibians (shown here) and is wiping out frog species worldwide. (Doug Woodhams, Smithsonian Tropical Research Institute)

“We would like to be moving faster to build capacity,” Gratwicke said. “One of our major hurdles is fundraising to build a facility to house these frogs. Until we jump that hurdle, we’re limited in our capacity to take in additional species.”

Nearly one-third of the world’s amphibian species are at risk of extinction. While the global amphibian crisis is the result of habitat loss, climate change and pollution, chytridiomycosis is at least partly responsible for the disappearances of 94 of the 120 frog species thought to have gone extinct since 1980.

“These animals that we are breeding in captivity will buy us some time as we find a way to control this disease in the wild and mitigate the threat directly,” said Woodhams, who was the lead author of a whitepaper Mitigating Amphibian Disease: strategies to maintain wild populations and control chytridiomycosis. This paper, published in Frontiers in Zoology, systematically reviews disease-control tools from other fields and examines how they might be deployed to fight chytrid in the wild. One particularly exciting lead in the effort to find a cure is that anti-chytrid bacteria living on frog skin may have probiotics properties that protect their amphibian host from chytrid by secreting anti-fungal chemicals. Woodhams recently discovered that some Panamanian species with anti-chytrid skin bacteria transmit beneficial skin chemicals and bacteria to their offspring. The paper, Social Immunity in Amphibians: Evidence for Vertical Transmission of Innate Defenses, was published in Biotropica in May.

“We are all working around the clock to find a cure,” Gratwicke said. “Woodhams’ discovery that defenses can indeed be transferred from parent to offspring gives us hope that if we are successful at developing a cure in the lab, we may find a way to use it to save wild amphibians.”

The Smithsonian Conservation Biology Institute serves as an umbrella for the Smithsonian Institution’s global effort to understand and conserve species and train future generations of conservationists. Headquartered in Front Royal, Va., SCBI facilitates and promotes research programs based at Front Royal, the National Zoo in Washington, D.C., and at field research stations and training sites worldwide.

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Media only: contact Lindsay Renick Mayer, Smithsonian’s National Zoo, 202-633-3081

Snakes where frogs should be!

As the fungal disease, chytridiomycosis, wipes out frogs and other amphibians across Panama, snakes appear to be more common than previously—but are they really, and will they last?

Eyelash viper

Chad Montgomery took this photo of an eyelash viper, Bothriechis schleglii, eating a frog in El Cope, Panama, one of the most studied frog decline sites here.

Panama’s ongoing “Amphibian Armageddon” completely changes who eats whom—aka the food chain—near the highland tropical streams where frogs and amphibians used to abound.

Researchers from the Panama Amphibian Rescue and Conservation Project’s latest expedition to Cerro Brewster in Central Panama report that where the frogs used to be, they are now seeing snakes—deadly eyelash vipers, to be exact.

This weekend my family was visiting from the United States and we ventured out on my favorite easy day trip from Panama City–a drive up to El Valle, a little town nestled in the crater of an extinct volcano.

Our first stop was El Nispero, a small private zoo, home to the El Valle Amphibian Conservation Center, EVACC, a project initiated by the Houston Zoo with some logistical support from the Smithsonian Tropical Research Institute.

EVACC is housed in a new building—with a beautiful small exhibit about Panama’s endangered frogs where you can see one of the last remaining golden frogs, Atelopus zeteki—named for James Zetek, one of the founder’s of STRI’s Barro Colorado Island research station in the 1920’s.

Edgardo Griffith is pretty much the powerhouse behind EVACC. He was in the lab there and was kind enough to take a break to talk to me about the most recent rescue project trip up to Brewster Hill.

The last visit to Brewster, which also included a big group of people from the Cheyenne Mountain Zoo in Colorado, was in November, 2009.  That team found a lot of frogs, but many of them were already infected with the fungus.

This time they found very few frogs, although they were psyched to have found a female Altelopus limosus, the Limosa harlequin frog, which the rescue project recently bred in captivity.

Instead they found a lot of snakes. Edgardo speculated that because there are fewer frogs it is not so much that there are more snakes, but that the snakes have to work harder to find frogs and are concentrated around the streams where a few frogs remain, so the team was just running into them more often.  But without more careful work, it is hard to say.

Chad Montgomery, now a professor at Truman State University in Missouri, did his post-doctoral research with Karen Lips from the University of Maryland on the effects of amphibian declines on frog predators at El Cope, one of the most studied frog decline sites in Panama.

He told me: “In 2005, the first year following the amphibian decline, we saw a change in the snake community, with snake species that are more dependent on amphibians as food (such as Sibon and Leptodeira) becoming less common relative to those snake species that are not as reliant on amphibians as prey (such as Oxybelis and Dipsas).”

“The ecosystem can’t support the previously large snake community,” he said. “Ultimately, loss of amphibians probably causes local extinction of some snake species and severely reduced population sizes in those species that remain.”

According to Julie Ray, the director of the La Mica Biological Station in El Cope, it’s unusual to see so many eyelash vipers, which have declined in El Cope following the frog decline. Eyelash vipers feed on frogs, lizards, mice, etc. She also said that Fer de lance, Panama’s most poisonous snake, actually feed on dying and dead frogs.

One of the truths that the rescue project reveals is how little we still know about playing Noah.  Many of Panama’s endangered frogs have never been studied in the wild or kept in captivity.

Not only do rescue project researchers have to figure out what frogs eat and what they need to survive and reproduce in a zoo, they still have no idea how their habitat will change as a result of the disease and when, if ever, it will be possible to reintroduce captive frogs back into the wild. We need to know much more about how frog extinctions change insect and animal communities…and that take precious time and money, which is why frog rescue projects need your support.

–Beth King, Smithsonian Tropical Research Institute

Jumpin’ Jack Flash!

Rain forest rocket frog (Silverstoneia flotator)

Rain forest rocket frog (Silverstoneia flotator)

Cute Frog of the Week: January 17, 2011

Okay, so this little guy can’t leap very far, but it sure appears like he’s trying here! Silverstoneia flotator (formerly Colestethus flotator), known as “rocket frogs,” live in the humid lowlands of Costa Rica and Panama. Because these cuties are actually a non-poisonous member of the poison dart frog family, they lack the bright warning colors of their well-defended cousins. There’s little information out there about these rocket frogs, but the International Union for Conservation of Nature lists them as least concern because they have a wide distribution and a large population. That’s at least some good news for our froggie friends! You can listen to their interesting vocalization on the Smithsonian Tropical Research Institute’s site.

Photo credit: Brian Gratwicke, Panama Amphibian Rescue and Conservation Project.

Banded horned tree frog (Hemiphractus fasciatus) ALL-NEW frog ringtones: Download the rainforest rocket frog’s call!

Every week the Panama Amphibian Rescue and Conservation Project posts a new photo of a cute frog from anywhere in the world with an interesting, fun and unique story to tell. Be sure to check back every Monday for the latest addition.

Send us your own cute frogs by uploading your photos here:

Frog Fantasmas

Jar of frogs

Researchers collected these dead frogs from sites where the fungus is moving through. (Photo credit: Karen Lips, University of Maryland)

Booo! Halloween’s over but ghost stories linger. In Panama, holiday season has begun! Nov. 3 marked the start of a long string of holidays–Independence from Colombia and from Spain this month, Mother’s Day, Chaunukah and Christmas in December, summer vacation for kids during the dry season, and ending up with Carnival festivities in February and back to school in March.

Yesterday my family piled into the car for the day-long drive up into the Chiriqui highlands near the border of Panama and Costa Rica.

We slept very well last night in the cool mountains where it’s extremely quiet compared to our home on the border of Soberania National Park in the lowlands where they say that the night time forest sound reaches 50 decibels–and a big part of that sound comes from frogs.

For some reason that no one understands, the chytrid fungus pathogen doesn’t seem to kill frogs in the lowlands, where it is sometimes found, but it decimates all amphibian populations along highland streams.

Earlier this month I had the wonderful opportunity to take an interpretation course offered by the National Association for Interpretation as part of a USAID tourist guide training program organized by Panama’s Association for Sustainable Tourism (APTSO). Each of the student guides was asked to share a story that they tell visitors to Panama that touches their hearts.

Carlos Fonseca, a young guide from Chiriqui, told that he and his brother used to spend summer days playing along streams in the highlands where they loved to find frogs…colorful frogs with pale white underbellies and even glass frogs that you can see through! About ten years ago, the chytrid epidemic passed through, and now the kids who play there don’t even know that there were frogs there.

Insects and birds dominate a cloud forest soundscape that used to ping and croak.

So, we’ll go for long walks in the woods on our weekend trip–we will see rainbows and maybe even a resplendant quetzal–and we’ll keep our eyes open for survivors–the few frogs that either managed to escape or were resistant to the disease.

Due to the vision of researchers like Karen Lips, from the University of Maryland, who first saw the fungus coming into Panama from Costa Rica, Roberto Ibanez, from the Smithsonian Tropical Research Institute and Brian Gratwicke from the Smithsonian’s National Zoological Park, a rescue effort was mounted to save Panama’s frogs.  Now, with support from Panama’s Environmental Authority (ANAM) and Summit Nature Park in Panama and eight other partner institutions in the United States, the Panama Amphibian Rescue and Conservation project rescues frogs in Eastern Panama where the fungus hasn’t been yet. It is one of the few examples of proactive conservation of species that otherwise would be doomed, and, to that end, offers a kind of hope that is rare in this world.

–Beth King, Smithsonian Tropical Research Institute

Guppy Travels: Day Two

Lindsay and gladiator frog

Before I had even set my luggage down, we were in the Panamanian rainforest looking for frogs.

The night quest—it’s not quite the childhood sport I remember. Sure, your heart is thumping rapidly and you–the frogger–have only moments to figure out the most effective way to wrap your hands around the frog without letting it escape. And when you finally do get your hands around him, you’re spellbound by the feeling of the animal perched there. But I had never actually caught frogs at night as a kid and in the first 24 hours here I’ve found myself on two nighttime frog hunts in the rainforest—one within hours of my plane touching down.

Hello, little frog. I flew 2,071 miles today just to meet you!

During Saturday night’s excursion, I held a red-eyed tree frog in my hand, watched as two tungara frogs in amplexus whipped up a froth of eggs, spotted more than one cane toad and got a good look at the hourglass pattern on the aptly named hourglass frog. Even before I laid eyes on a frog, though, I was swept up in the sounds of a richly diverse world. The chucking of the tungura frogs calling to mates, the chirping of the red-eyed tree frog as air pushes through its larynx. If these are the prima divas (and divos) in the opera of the natural world, then the insects are definitely the orchestra.

Gladiator frog

Although red-eyed tree frogs are quickly becoming one of my favorite species, this gladiator frog stole my heart on our second night of frogging.

We also ran into a Smithsonian Tropical Research Institute frog researcher in the forest. As I understand it, he was studying what combination of sounds and vibrations elicit a response—vocal and physical—from a potential mate. With his camera, we were able to see the world through infrared, including an unknowing red-eyed tree frog who looked eerily supernatural through this lens.

Last night’s excursion was a little different. Certainly more muddy and wet. My first spotting was of a pair of tungura frogs in amplexus. We collected them for a photo shoot before setting them free this morning. We also tracked down two red-eyed tree frogs by following their sound, standing under the tree that seemed to be making all the noise and peering up into the branches as two pairs of big red eyes peered back down at us. Perhaps my favorite discovery of the night was a gladiator frog the size of the palm of my hand. We didn’t collect this guy, but we did spend some time taking beauty shots of him. And oh how beautiful he was.

What is so markedly different about my hunt for frogs now, as an adult, is the feeling of gratitude and relief that I experience each time I see a frog in the wild. Relief that I am in the presence of a living, presumably healthy animal that doesn’t yet need an ark to survive the wave of chytrid in the way many of the highland species do. And relief that even though as an adult I am cursed with the ability to understand just how grave the situation is for amphibians, I am blessed to be part of a project that aims to ensure a biodiverse world for the next few generations of froggers looking for a good night quest.

-Lindsay Renick Mayer, Smithsonian’s National Zoo