Mission Critical: Amphibian Rescue

This award-winning documentary featuring our race to find a cure for a deadly amphibian disease and to build an amphibian ark in Panama is now available for FREE.  Watch the trailer below and download the full feature if you would like to see more on the itunes store for a limited time only.

CLICK HERE to download the full episode of Smithsonian Networks Mission Critical: Amphibian Rescue film. FREE FOR A LIMITED TIME ONLY!

Rescue Project Successfully Breeds Endangered Frog Species

 

Limosa harlequin frog (Atelopus limosus) baby on a U.S. quarter.

Limosa harlequin frog (Atelopus limosus) baby on a U.S. quarter. (Photo by Brian Gratwicke, Smithsonian Conservation Biology Institute)

The limosa harlequin frog (Atelopus limosus), an endangered species native to Panama, now has a new lease on life. The Panama Amphibian Rescue and Conservation Project is successfully breeding the chevron-patterned form of the species in captivity for the first time. The rescue project is raising nine healthy frogs from one mating pair and hundreds of tadpoles from another pair.

“These frogs represent the last hope for their species,” said Brian Gratwicke, international coordinator for the project and a research biologist at the Smithsonian Conservation Biology Institute, one of six project partners. “This new generation is hugely inspiring to us as we work to conserve and care for this species and others.”

Nearly one-third of the world’s amphibian species are at risk of extinction. The rescue project aims to save priority species of frogs in Panama, one of the world’s last strongholds for amphibian biodiversity. While the global amphibian crisis is the result of habitat loss, climate change and pollution, a fungal disease, chytridiomycosis, is likely responsible for as many as 94 of 120 frog species disappearing since 1980.

Between its facilities at the Smithsonian Tropical Research Institute in Gamboa, Panama, and the El Valle Amphibian Conservation Center in El Valle, Panama, the rescue project currently cares for 55 adult limosa harlequin frogs of the chevron-patterned form and 10 of the plain-color form. The project has had limited success breeding the plain-color form of this species, and has successfully bred other challenging endangered species, including crowned treefrogs (Anotheca spinosa), horned marsupial frogs (Gastrotheca cornuta) and toad mountain harlequin frogs (A. certus).

Each species requires its own unique husbandry to thrive and breed. The project’s animal care team and scientists learn husbandry techniques as they work with a limited number of individuals. Jorge Guerrel, conservation biologist at the Smithsonian Tropical Research Institute, arranged rocks in the breeding tank to create the submerged caves that appear to be the preferred egg deposition sites for limosa harlequin frogs. Like other Atelopus species, tadpoles require highly oxygenated, gently flowing water between 22 and 24 degrees Celsius. The tadpoles’ natural food is algal film growing on submerged rocks, which Guerrel and his colleagues re-created by painting petri dishes with a solution of powdered spirulina algae, then allowing it to dry.

The mission of the Panama Amphibian Rescue and Conservation Project is to rescue amphibian species that are in extreme danger of extinction throughout Panama. The project’s efforts and expertise are focused on establishing assurance colonies and developing methodologies to reduce the impact of the amphibian chytrid fungus so that one day captive amphibians may be reintroduced to the wild. Current project partners include Cheyenne Mountain Zoo, Houston Zoo, Smithsonian’s National Zoological Park, Smithsonian Tropical Research Institute and Zoo New England.

Lindsay Renick Mayer, Smithsonian’s National Zoo

Frog Poetry and the Washington Post

Washington Post

On Dec. 30, the Washington Post ran a front-page story about the rescue project.

The year ended on a high note for the Panama Amphibian Rescue and Conservation Project. William Booth, a science writer for the Washington Post, joined rescue project researchers on a field expedition and his story about the rescue project came out on the front page of the Post on Dec. 30. The story inspired one reader, Tim Torkildson, to share a lovely poem about frogs and the disease that is wiping them out.

Booth also did this NPR interview about his recent trip to Panama.

If you saw the story and are interested in making a donation to the rescue project, please follow this link to the National Zoo’s website.

THE FROG
by Tim Torkildson

The frog is an amphibian
Who thrives most ev’rywhere,
From the dry Namibian
To just off ol’ Times Square.
The ones who have a bumpy skin,
With warts and pits and nodes,
Are the closest Phylum kin;
We simply call them toads.
The bullfrogs in the early spring
give ponds reverberation
With their raucous verbal fling,
Attempting procreation.
The have a courtship ritual
that’s called, I think, amplexus,
Which gives them fits conniptual
Between the two odd sexes.
A little boy will manage to
Corral a tadpole, yes,
And give it quite a slimy view
Right down his sister’s dress!
And did you know the urine from
a pregnant lady will
cause some frogs to lay a scum
of eggs, with no male thrill?
And so they’re useful critters,
As the French will tell you so;
Their legs taste good in fritters,
Are mistaken for turbot.
And what of cane toads, mind you,
Where, if you lick the skin,
The psychedelics blind you
To sorrow, grief and sin?
But frogs, those little gargoyles,
Which are funny in cartoons,
Are engaged in lethal broils
That leaves their lives in ruins.
A fungus known as “Bd” kills
The frogs down in Belize,
Then jumps the valleys and the hills
So others it may seize.
The Costa Rica Golden Toad
Is now extinct, alack.
More are headed down that road,
Since habitat is slack.
Toxins give some frogs three legs,
Which doesn’t help them jump.
Instead they are like clumsy kegs
Who in the water flump.
Scientists preserve some frogs
In habitats in labs.
Dressed in their starched, stiff white togs
They keep meticulous tabs.
To save the frogs, oh please donate
A dollar or a yuan,
So the polliwog birth rate
Will someday be a shoo-in!

Using genetic tools to understand and manage chytridiomycosis

Lowland leopard frog (Lithobates yavapaiensis)

The lowland leopard frog is the focus of SCBI postdoc Anna Savage's work looking at the relationship between genes and chytrid resistance.

Chytridiomycosis, the disease wiping out frog species around the world, was described in 1999 by a team of researchers at the Smithsonian and the University of Maine. Today, in addition to creating an insurance population for various Panamanian species, the Smithsonian Conservation Biology Institute aims to find a way to manage this disease. One of the most promising solutions to stopping the killer may rest in genetics. SCBI scientists are looking to identify genes within frogs that provide resistance to the pathogen or that make them more susceptible to it.

Researchers pursuing this approach are optimistic that genetics could provide different answers than those offered by probiotics, which SCBI is also pursuing. The genetic approach is one based on natural selection.

“If you look across species, including humans, diseases rarely wipe out an entire species without any evidence of resistance, regardless of how virulent they are,” said Anna Savage, an postdoctoral fellow in SCBI’s Center for Conservation and Evolutionary Genetics studying the genetics of chytrid. “Immune systems are so complex that there’s a strong possibility for the development of resistance. The probability that a species develops no resistance to a disease is rather small.”

Genetics research within the last decade has identified frogs with varying degrees of resistance to chytrid. Savage is focusing her research on the lowland leopard frog (Lithobates yavapaiensis), which exhibits an intermediate level of resistance to the pathogen. Some individuals demonstrate resistance while others of the same species die if infected with chytrid. The identification of genetic variations between the individuals holds the potential of being the answer between life and death. One of the new frontiers for genetic research is the examination of a frog species’ immune system genes.

“If we can identify the genes responsible for resistance, we can breed the animals in captivity to ‘spread’ this genetic resistance and give adaptation a headstart,” Savage said. “This area of research holds the potential for creating populations of self-sustaining frogs that confer resistance to the rest of the population through reproduction.”

Anna Savage with bullfrog

Savage's research could hold the key to putting a stop to a deadly pathogen killing frogs around the world.

In order to understand a frog’s response to chytrid, the focus must be broadened to understanding how immune system genes interact with one another and which ones are being expressed during resistance. Savage is using this approach to understand chytrid susceptibility in lowland leopard frogs that are being raised at the Smithsonian’s National Zoo. This approach could potentially help scientists identify genes responsible for chytrid resistance. While this type of research shows considerable potential, researchers are only just beginning to scratch the surface.

“Disease outcomes from chytridiomycosis can depend on several factors,” said Brian Gratwicke, SCBI wildlife biologist and Panama Amphibian Rescue and Conservation Project international coordinator.  “Some frogs appear to have innate resistance to the disease and produce antimicrobial peptides from glands in their skin. It is possible that some might acquire resistance through exposure, while other frogs have beneficial anti-fungal skin bacteria or a behavioral preference for temperatures that are bad for the fungus. As the fight against chytrid continues, we remain hopeful that the answers are out there and that Dr. Savage’s work will give us some insight into how this system really functions.”        

–Will Lazaro, Smithsonian’s National Zoo

(Frog photo by Jared Grummer; photo of Anna Savage by Dennis Caldwell)

Celebrating tadpole diversity

Tadpoles

The ability of certain Panamanian species to survive will depend on the ability of the rescue project to perfect specialized care for the individual species. (Photo by Lindsay Renick Mayer, Smithsonian

When we talk about frog diversity, we always mention how many species there are, or how they are found all over the world. We say how much frogs vary in size, or how colorful they can be. This is all true: there are more than 4,900 frog species, found on every continent, ranging from ½-inch long to more than a foot, that come in every color of the rainbow. It makes sense, then, that frogs are just as diverse during their other stages of the life cycle. Tadpoles, in fact, are among the most diverse vertebrates on Earth and are themselves morphologically and behaviorally unique from their adult counterparts.

Special Adaptations

Depending on the species, tadpoles can stay in the larval stage from eight days to two years, and vary in length from 1 to 4 inches. Overall, there is greater tadpole diversity in the tropics, but variations occur within habitats, as well. Even tadpoles with the same feeding habits can have diverse mouth shapes or behaviors. For example, tadpoles of the Asian horned frog (Megophrys montana) have an upturned mouth because they eat from the surface. Recently, however, scientists have observed a Honduran tadpole called Duellmanohyla soralia that also eats from the surface, but has a mouth in the more traditional spot. Instead, the Duellmanohyla soralia turns its body upside-down to reach the surface.

“We see tadpoles solving the same problems of survival in different ways,” says Dr. Roy McDiarmid, an amphibian zoologist and tadpole expert at the National Museum of Natural History. “This is where their diversity derives from.”

These variations show how tadpoles’ features are shaped largely by their surrounding environments. For example, tadpoles seem especially good at responding to strong predator presence. Over time tadpoles can grow their tails longer and deeper if there are numerous predators, allowing them to swim faster and look bigger. For European common frog (Rana temporaria) tadpoles, longer tails increase their chances of escape from predators up to 30 percent, according to the Institute of Zoology.

Like tail length, other adaptations can protect tadpoles from being eaten. While the majority of tadpole species have brown or faded coloration, several are multicolored. Contrary to its name, Cope’s gray tree frog (Hyla chrysoscelis) tadpoles grow red tails in response to the presence of dragonflies. Called aposematism, vibrant colors make these tadpoles appear larger or distasteful to their predators.

Researchers have only recently discovered other survival mechanisms that tadpoles have developed. In 2006, scientists discovered that if attacked, red-eyed tree frog (Agalychnis callidryas) embryos can hatch themselves within seconds and escape into the water below. These embryos can interpret vibrations on the water with astonishing precision.

“It turns out that when a snake bites into a gooey mass, all the embryos try to wiggle free,” Karen Warkentin, a biologist working at the Smithsonian Tropical Research Institute in Panama, told National Geographic.  “A wasp’s more focused attack prompts only neighboring eggs to hatch. And a rainstorm triggers nothing at all.”

Other recent research has looked at tadpole sensory input, such as smell and sound. In 2009, researchers at the University of California Davis determined that wood frog (Rana sylvatica) tadpoles can “smell” their primary predator, the salamander. The “odor” of a salamander in the water caused tadpoles to freeze. The strength of the scent determined how long the tadpoles remained still. In 2010, Dr. Guillermo Natale discovered the first evidence of aural larva communication. Natale heard tadpoles of the Bell’s horned frog (Ceratophrys ornate) “screaming” underwater when a threat was present.

Discovery

Tadpole

The amount of tadpole diversity rivals that of their adult life forms. (Photo by Brian Gratwicke, Smithsonian Conservation Biology Institute)

New and unpredictable tadpole discoveries continue to go on worldwide. For example, biologists at the Australian Museum in Sydney recently discovered that tadpoles of the vampire flying frog (Rhacophorus vampyrus) have small black fangs, instead of traditional mouthparts. In general, scientists estimate that more than 1,000 frog species have yet to be discovered, not to mention all the intricacies of their life stages.

Tadpoles are also essential for understanding the dramatic decline in frog populations. Chytrid, the epidemic that has affected 30 percent of the world’s amphibian population, is the lead cause of this decline. In tadpoles, chytrid only infects the keratin around their mouths. However, as they metamorphose into frogs, chytrid fatally spreads throughout their bodies. By studying tadpoles, we can better understand how frogs contract and carry chytrid.

“When frog species are disappearing like they are, you would want to know what’s going on at each stage of the life cycle, egg to larva to juvenile to adult–everything,” McDiarmid says.

The Challenges of Breeding

For the Panama Amphibian Rescue and Conservation Project, every tadpole means the chance for a species to survive. But because many of the rescue project’s priority species have never been kept or bred in captivity before, rearing tadpoles can mean a steep learning curve.

“Breeding frogs isn’t just about putting a male and female together and hoping for eggs,” said Lindsay Renick Mayer, spokesperson for the rescue project. “It’s about specialized husbandry for each individual species among a diverse array and unfortunately for some of these species we’re learning those skills even as the species dwindles down to just a few remaining individuals. Whether these species are one day returned to the wild depends on the rescue project’s success in perfecting the variety of care in a short period of time.”

Nadia Hlebowitsh, Smithsonian’s National Zoo

New experiment may offer hope for frogs facing chytrid

Probiotics bath

The golden frogs were given a bath in one of four probiotic solutions. (Photo by Brian Gratwicke, Smithsonian Conservation Biology Institute)

We usually think of bacteria as bad for us, but that isn’t always the case. For us humans, the most common examples of helpful bacteria, or probiotics, live in yogurt. Now, scientists believe amphibian probiotics may be the key to fighting chytridiomycosis, the fungal disease devastating frogs around the world.

A few years ago, Reid Harris, a biology professor at James Madison University, discovered that local salamanders that could survive chytrid played host to bacteria in their skin. Now, Brian Gratwicke, a research biologist at the Smithsonian Conservation Biology Institute, is collaborating with a team from Virginia Tech, James Madison, Villanova and Vanderbilt Universities in an experiment to see if similar bacteria can protect the Panamanian golden frog, which he calls “the poster-child for amphibian conservation.”

The first step is to find a probiotic that will stick to the golden frogs. In early December, the team began giving golden frogs baths using four different types of bacteria. Researchers gathered the potential probiotics from frogs in Panama in 2009. The finalists were chosen based on their ability to prevent chytrid growth in lab tests, with a preference for bacteria that are common in close relatives of Panamanian golden frogs.

Every two weeks, each frog is swabbed to check whether its probiotic has made itself at home. The tests take some time, so a month and a half in, the team is still waiting for results to see which probiotics are sticking. But they do have some good news already.

“The bacteria haven’t been causing any problems with the frogs and they all look healthy,” said Gratwicke, who emphasizes how important it is to use only beneficial bacteria. In addition to tracking weight gain and other visible characteristics, Shawna Cikanek, a student at Kansas State College of Veterinary Medicine is using frog poop to study stress hormones to get a better picture of the animals’ overall health and whether the bacteria are causing any stress.

The probiotics that stick to the frogs for a full three months will move on to the next round of tests, when bacteria-shielded frogs will be infected with chytrid to check for any adverse effects.

“Hopefully, the bacteria are going to do their thing and protect these little guys,” said Matt Becker, a PhD candidate from Virginia Tech who is conducting the experiment. Whatever probiotics make the cut will be tested again on golden frogs bred in Panama before scientists develop a final plan.

So far, chytrid has defied attempts to stop it. Scientists may be able to selectively breed frogs resistant to chytrid, but there has been very little work done so far in that direction. But there are high hopes for probiotics’ potential to protect frogs. “It’s a long shot, but it’s our best shot,” said Gratwicke.

Becker hopes that one day, probiotics will allow Panamanian golden frogs to return to their homes. “These guys are really neat and it’s so sad not to see them in the wild,” he said. “We have a moral obligation since indicators are pointing to humans as major spreaders of the disease through the frog trade.”

Meghan Bartels, Smithsonian’s National Zoo

Smithsonian scientists survey frogs in the Peruvian Andes

Acancocha water frog (Telmatobius jelskii)

Last December two researchers from the Smithsonian Conservation Biology Institute spent two weeks in Peru surveying the Acancocha water frog (Photo by Jessica Deichmann, SCBI)

Imagine measuring the tail of a squirmy, inch-long tadpole. Now imagine doing that where the air is thin enough to make you dizzy, a hail storm is about to start and you just spent 45 minutes up to your elbows in a freezing cold stream.

Last December, Jessica Deichmann, a research scientist with the Smithsonian Conservation Biology Institute, and Ed Smith, a biologist at the Smithsonian’s National Zoo’s Amazonia Exhibit, spent two weeks doing just that to complete a survey of the Acancocha water frog (Telmatobius jelskii). They were participating in a frog surveying trip for SCBI’s Center for Conservation Education and Sustainability’s Peruvian Biodiversity Monitoring and Assessment Program (BMAP). The program lends Smithsonian scientific expertise to gas and oil companies to assess the effects of development projects on local plants and animals. This information is used to improve restoration work, and reduce environmental impacts of future development. This was the third survey along the path of a natural gas pipeline constructed in 2009 that runs from the Amazon over the Andes to the Pacific Ocean—about 250 miles.

The Acancocha water frog is found only in the cold clear streams of the high-elevation Peruvian Andes. The frog is one of about 40 species researchers are surveying around the construction of this particular pipeline. Scientists chose this species because although historically it has been fairly abundant, it lives in a relatively small area with precise habitat requirements. When individuals of a species are clustered together, it’s easier to lose the entire species.

“You always worry about frogs with small geographic ranges—not just frogs, but any species,” Deichmann said.

When you think of the Peruvian Andes, you probably think of Macchu Picchu, a lush green mountainside where, as Smith jokes, “if you sit too long you have orchids growing on you.” Smith and Deichmann, however, were in a very different ecosystem called puna and sometimes nicknamed equatorial tundra. Puna is found high in the Andes, where trees no longer grow, rain is scarce, and nights are freezing. The team spent much of its time about 15,000 feet above sea level, where the air is so thin that breathing is hard until you get used to it. “For us lowland landlubbers, that alone was an exhausting business,” Smith said.

Peruvian Andes

Smith and Deichmann were in a very different ecosystem called puna and sometimes nicknamed equatorial tundra. (Photo by Jessica Deichmann, SCBI)

The team—Deichmann, Smith and two Peruvian biologists—took samples at twelve sites where the pipeline crosses mountain streams. At each site, they spent about 45 minutes upstream, elbow-deep, feeling for frogs and tadpoles. For each tadpole, first, the team swabbed its mouth for a sample for chytrid testing. The team also recorded the tadpole’s body length, tail length, mass, and developmental stage, and photographed each sample before the animal was returned to the stream.  They also took measurements of the stream itself. Then the team repeated the whole process downstream of the pipeline. Any one site could take five or six hours.

But Deichmann is clear that the process was worth it. “Just to find frogs and tadpoles was exciting,” she said. “Especially adults—after hours and hours in freezing cold water and your arms are purple, when you find your first frog it’s just so exciting.”

The team hasn’t processed the data yet, but their initial measurements suggest some good news: so far, they have seen no obvious effects as a result of the pipeline. However, although the team found hundreds of tadpoles, they found only 10 adult frogs in all the sample areas.

Unfortunately, that suggests chytrid is playing a role in shaping the population structure. The skin fungus follows skin keratin proteins, the amphibian equivalents of those found in human skin calluses, hair and nails. Tadpoles usually survive chytrid infection because they have keratin only around their mouths. As they develop their keratin “suit of armor,” frogs are left vulnerable to the disease that has decimated them in less than half a century.

“From metamorphosis, something called the ‘chytrid clock’ starts ticking,” Smith said. In adults, “chytrid interferes with water balance, usually in a lethal way.” Because of this, chytrid-struck populations often consist of many tadpoles and a few adults.

And according to the previous surveys, “at pretty much all the sites where frogs and tadpoles were present, chytrid was present,” Deichmann said.

Mountain stream

At each of 132 sites, the team spent about 45 minutes upstream, elbow-deep, feeling for frogs and tadpoles. (Photo by Jessica Deichmann, SCBI)

But until they have the results from lab tests on the mouth swabs the team took, they won’t have the full picture about how the disease is affecting these populations.  And chytrid isn’t the only danger these frogs face. “In a lot of our streams we were, not surprisingly but disappointingly, finding trout,” an invasive predator, Smith said.

Deichmann and Smith agree that the data they collected will be useful for conservation efforts. “Monitoring populations now gives us a baseline without which we can never know what’s changed,” Smith said. The team has a tentative follow-up survey scheduled for the dry season of 2012, during the northern hemisphere’s summer. Deichmann hopes that the data from this December’s trip will allow the program to modify the survey protocol to make sure future trips are gathering the most helpful data possible.

And of this expedition? “It was an amazing trip,” Deichmann said. “The habitats are stunning, the scenery is stunning. You’re at the top of the world.”

Meghan Bartels

Defenders Urges USFWS to Ban Importation of Live Frogs That May Have Chytrid

Chytrid infected frog

Defenders of Wildlife has submitted a proposal to the U.S. Fish and Wildlife Service to ban the importation of live frogs unless they are accompanied by a health certificate verifying that they are free of the chytrid, which killed the frog shown here. (Photo by Brian Gratwicke, Smithsonian Conservation Biology Institute)

The global amphibian trade has been indicted as the culprit in the spread of the deadly chytrid fungus. A study published in New Scientist  calls for an amphibian quarantine to help slow the disease’s spread.

The study sequenced the genomes of 20 samples of Bd, collected in Europe, Africa, North and South America and Australia. They found that 16 of the 20 samples were genetically identical.

The researchers say the explanation for this is simple, that world-wide trade in amphibians enabled the spread of this disease.

The researchers suggest that countries quarantine all imported amphibians and only allow them to stay if they are not infected.

Defenders of Wildlife, a partner in the Panamanian Amphibian Rescue and Conservation Project, has submitted a proposal to the U.S. Fish and Wildlife Service to ban the importation of live frogs unless they are accompanied by a health certificate verifying that they are free of the chytrid fungus.

“Billions of frogs are traded internationally each year for human consumption, and that industry is responsible for depleting wild populations, spreading deadly disease, and allowing invasive species to destroy the health of native ecosystems,” said Alejandra Goyenechea, counsel for the international conservation programs for Defenders of Wildlife.

Defenders is working with the upcoming CITES Animals Committee to ensure that the international trade of frogs is not detrimental to their survival and with CITES Parties to bring awareness on the international trade of frog legs with our report.

Cindy Hoffman, Defenders of Wildlife

National Zoo Successfully Collects Sperm Samples to Save Endangered Frog

Gina Della Togna, an SCBI PhD student and native Panamanian, is one of the researchers in charge of the sperm collection procedure.

Gina Della Togna, an SCBI PhD student and native Panamanian, is one of the researchers in charge of the sperm collection procedure. (Photo courtesy of the Smithsonian Conservation Biology Institute)

With nearly one-third of all amphibian species at risk of extinction as the result of the deadly chytrid fungus, the Smithsonian’s National Zoo has taken a bold step toward preserving amphibian genes and the world’s incredible amphibian biodiversity. Researchers at the Smithsonian Conservation Biology Institute in Washington, DC, have begun to collect sperm samples from the Zoo’s collection of Panamanian golden frogs (Atelopus zeteki), which are extinct in the wild.

Although researchers have collected sperm samples from other amphibian species such as Mississippi gopher frogs and leopard frogs, there are no publications detailing sperm collection methods from Panamanian golden frogs. SCBI’s colleagues at the Maryland Zoo have aided in the process, providing advice to the SCBI researchers about the method to collect the frogs’ spermatozoa using hormonal stimulations.

“We currently have three other species of Atelopus in captive assurance colonies in Panama,” said Brian Gratwicke, an SCBI conservation biologist who leads the Zoo’s amphibian conservation program to curb global amphibian declines. “If we can freeze some of their sperm, golden frogs will be a model to secure the long-term genetic integrity of other toad species in similar situations.”

Gina Della Togna, an SCBI PhD student and native Panamanian, is one of the researchers in charge of the sperm collection procedure. Even though this is still a fairly new endeavor, Della Togna said she felt that it was easy compared to collecting sperm from mammals. After hormonal stimulation, spermatozoa are excreted in the urine from the frog’s cloaca, a multipurpose opening from which feces, urine and gases are expelled. This is in contrast to mammals, which possess specialized structures for the expulsion of waste and reproduction.

Atelopus zeteki sperm

A Panamanian golden frog sperm

Although sperm collection from this species has been successful, finding the most efficient and repeatable stimulation protocol is critical. Then, identifying the right cryoprotectant and freezing method will be another challenge. Researchers suspect that the cell component most likely responsible for the movement of the sperm, called a mitochondrial vesicle, has a unique structure compared to that of other animals.

“The mitochondrial vesicle is a very fragile structure,” Della Togna said. “Protecting this structure will definitely be one of our greatest challenges.”

Even in the face of numerous challenges, the research team overseeing the sperm collection and storage of the samples remains optimistic.

Pierre Comizzoli, an SCBI gamete biologist supervising the PhD project  is enthusiastic about the prospect of this endeavor and is charged with studying the complex golden frog sperm structure with Della Togna.

“It is always exciting to discover new biological mechanisms,” Comizzoli said. “Spermatozoa from each species have unique traits that needs to be well understood before developing preservation protocols.”

Other than its genetic and natural significance, the Panamanian golden frog is a meaningful symbol of culture for Panamanians. Pre-Columbian peoples used to make golden “huacas,” or sacred objects, in the image of these frogs, along with creating legends about these renowned frogs, which endure in the Panamanian countryside today, Della Togna said.

“This species does not exist anywhere else in the world,” Della Togna said. “You will find pictures and sculptures of it in local markets, in indigenous handcraft sales, and on lottery tickets, among places. Hopefully this project will help to ensure that one day you will be able to see them once again on the banks of Panamanian streams where they belong.”

Phil Jaseph, Smithsonian’s National Zoo

Double Whammy: Snake carries killer fungus

blunt-headed tree snake

Researchers recently confirmed that the fungus causing the lethal disease chytridiomycosis is present on nonamphibian carriers, such as this blunt-headed tree snake, in natural environments. (Photo courtesy of STRI)

The blunt-headed tree snake (Imantodes cenchoa) not only eats frogs and their eggs, it also carries the killer fungus that has wiped out more than 100 amphibian species worldwide.

A new study by Vanessa Kilburn and David Green from Canada’s McGill University with the Smithsonian Tropical Research Institute’s Roberto Ibáñez, in-country director of the Panama Amphibian Rescue and Conservation Project, confirms for the first time that the fungus causing the lethal disease chytridiomycosis is present on nonamphibian carriers in natural environments.

The team surveyed 13 species of lizards and 8 species of snakes from sites across Panama using a genetic test to identify fungal DNA in samples taken from the reptiles’ skin with a cotton swab. They found evidence of the disease on up to 32 percent of lizards (Anolis humilis) and on three different species of snakes.

The irony of a frog-eating snake that carries a killer frog disease is that it may eliminate its own food supply, leading to its own demise.

Beth King, Smithsonian Tropical Research Institute