A vigorous immune response to the chytrid fungus is associated with susceptibility to the disease

For frogs dying of the invasive chytridiomycosis disease, the leading cause of amphibian deaths worldwide, the genes responsible for protecting them may actually be leading to their demise, according to a new study published today in the journal Molecular Ecology by Smithsonian Conservation Biology Institute (SCBI) and University of Central Florida researchers.

The lowland leopard frog, found in river drainages in Arizona, is one of a few amphibian species in which some individuals survive infection by Batrachochytrium dendrobatidis chytrid fungus (Bd) while other individuals do not—even when they live in the same local population.

In a study of lowland leopard frogs infected with Bd, the fungus that causes the disease chytridiomycosis or chytrid, researchers found that frogs that died from the disease had higher expression of major histocompatibility complex and other immune system genes than frogs that survived it. Those genes help organisms fight off infections and foreign substances.

“This result was totally counterintuitive and the opposite of the pattern we expected to recover,” said Anna Savage, the study’s lead author, an associate professor in UCF’s Department of Biology and former postdoctoral fellow at SCBI’s Center for Conservation Genomics (CCG).

Comparison of differential gene expression in control, early infected, surviving and susceptible frogs in both the spleen (left) and skin (right). 

“My previous research on these immune genes showed that some variants were associated with higher survival to Batrachochytrium dendrobatidis, so I hypothesized that those genes were enabling the frogs to have a stronger immune response that would kill the fungus,” she said. “Instead, it seems like those stronger responses are linked to susceptibility, and the genes associating with survival are linked to reduced immune function.”

Savage said acquired immune responses can be very potent, require a lot of energy from the body and can sometimes produce toxic byproducts that harm the host and the pathogen.

“Immune responses are much more complex than just an on-off switch,” she said. “A big part of the immune system is regulating the type, timing and dosage of a particular response, and if any of those components get dysregulated, it can have extremely negative consequences.”

She said, for instance, Batrachochytrium dendrobatidis suppresses the host immune system by killing B and T lymphocytes. “Because those are the same cells that proliferate during acquired immune responses, producing lots of those cells might just be wasting energy on something that chytrid can easily destroy,” she said.

Amphibian populations are in decline around the world, with two-thirds of the world’s 8,000 species considered to be threatened and nearly 200 species that have already gone extinct in the last two decades. In the U.S., amphibian populations overall are declining at a rate of nearly 4 percent a year, with some areas, such as the Rocky Mountains and the West Coast, facing a higher rate of decline, according to the U.S. Geological Survey.

Although the researchers studied immune gene expression in lowland leopard frogs with chytridiomycosis, the findings may be useful for studying the disease in other frog species due to genetic similarities they share, Savage said.

 

Lowland leopard frogs were chosen for the study because their responses to chytridiomycosis vary from one individual to the next, unlike many other frog species that are completely susceptible to the disease or are completely resistant or tolerant.

This allowed the researchers to rule out genetic variation between species and pinpoint specific differences in lowland leopard frogs’ immune genes that predicted different responses to infection.

The frogs were collected in Arizona and shipped overnight to the Smithsonian’s National Zoo in Washington, D.C., where the infection experiments were conducted. Subsequent analyses of gene expression occurred at the SCBI’s Center for Conservation Genomics. Statistical analyses of the data were performed at UCF.

Robert Fleischer, senior scientist and head of the SCBI’s CCG, co-authored the study and was Savage’s main advisor for the research when she was a postdoctoral fellow at the Smithsonian. Fleischer said the results help in understanding why some frogs survive the disease and others do not.

“If we can solve this mystery, and we have taken a big step in that direction with this study, our hope and plan is to use this information to develop resources and strategies to mitigate the disease in the more susceptible species, and to counter the worldwide tide of extinction and endangerment caused by chytrid,” he said.

The researcher said the findings also show that acquired immune responses, such as those generated by vaccination, may not always be useful in combating invasive diseases of conservation concern.

Brian Gratwicke, a conservation biologist with SCBI; Katherine Hope, an associate veterinarian with the Smithsonian’s National Zoo; and Ed Bronikowski, senior curator of the Smithsonian’s National Zoo, were study co-authors as well.

The research was funded by a Smithsonian Institution Competitive Grants Program for Science grant, the Smithsonian’s Center for Conservation Genomics and a Smithsonian Institution Molecular Evolution Postdoctoral Fellowship.

Anna E. Savage, Brian Gratwicke, Katharine Hope, Edward Bronikowski, Robert C. Fleischer. Sustained immune activation is associated with susceptibility to the amphibian chytrid fungusMolecular Ecology, 2020; DOI: 10.1111/mec.15533

written by Robert Wells (University of Central Florida)

Mass amphibian extinctions globally caused by fungal disease

An international study led by The Australian National University (ANU) has found that a fungal disease has caused dramatic population declines in at least 501 amphibian species, including 90 extinctions, over the past 50 years. The study involved collaborations with 41 different amphibian and wildlife disease experts from around the world. Smithsonian scientists contributed data from Panama—one of the worst-hit areas of the world by the disease—for the study.

Of the 90 confirmed extinctions of frogs across the globe, eight of those species were from Panama. Another 52 species of frogs in Panama have experienced more than a 90 percent decline.

“This study confirms that we are not dealing with a unique problem in Panama,” said Brian Gratwicke, amphibian biologist, international coordinator of the Panama Amphibian Rescue and Conservation Project, and one of the co-authors of the study who provided data. “If we or anyone does find a solution or cure for chytrid, it will likely have global implications.”

Captive Assurance Colonies

Collaborators like Smithsonian scientists allowed the lead researchers from ANU to get a first-hand insight into the conditions on-the-ground in countries around the world.

Chytridiomycosis, which eats away at the skin of amphibians, has completely wiped out some species, while causing more sporadic deaths among other species. Amphibians, which commonly live part of their life in water and the other part on land, mainly consist of frogs, toads and salamanders.

The deadly disease is present in more than 60 countries – the worst affected parts of the world are Australia, Central America and South America. The researchers found that chytridiomycosis is responsible for the greatest loss of biodiversity due to a disease.
The disease is caused by chytrid fungus, which likely originated in Asia where local amphibians appear to have resistance to the disease.

The unprecedented number of declines places chytrid fungus among the most damaging of invasive species worldwide, threatening similar numbers of species as rats and cats.

Lead researcher Ben Scheele, Fenner School of Environment and Society at ANU, said highly virulent wildlife diseases, including chytridiomycosis, were contributing to the Earth’s sixth mass extinction.

“The disease we studied has caused mass amphibian extinctions worldwide. We’ve lost some really amazing species,” said Scheele.

He said more than 40 frog species in Australia had declined due to this disease during the past 30 years, including seven species that had become extinct.
“Globalisation and wildlife trade are the main causes of this global pandemic and are enabling disease spread to continue,” said Scheele. “Humans are moving plants and animals around the world at an increasingly rapid rate, introducing pathogens into new areas.”

Scheele said improved biosecurity and wildlife trade regulation were urgently needed to prevent any more extinctions around the world.

“We’ve got to do everything possible to stop future pandemics, by having better control over wildlife trade around the world.”

Scheele said the team’s work identified that many impacted species were still at high risk of extinction over the next 10–20 years from chytridiomycosis due to ongoing declines.

“Knowing what species are at risk can help target future research to develop conservation actions to prevent extinctions.”

Scheele said conservation programs in Australia had prevented the extinction of frog species and developed new reintroduction techniques to save some amphibian species.

“It’s really hard to remove chytrid fungus from an ecosystem – if it is in an ecosystem, it’s pretty much there to stay unfortunately. This is partly because some species aren’t killed by the disease,” he said.

“On the one hand, it’s lucky that some species are resistant to chytrid fungus; but on the other hand, it means that these species carry the fungus and act as a reservoir for it so there’s a constant source of the fungus in the environment.

Video by Katie Garrett and Jonathan Kolby

Citation to the Paper: Scheele, B.C., Pasmans, F., Skerratt, L.F., Berger, L., Martel, A., Beukema, W., Acevedo, A.A., Burrowes, P.A., Carvalho, T., Catenazzi, A., De la Riva, I., Fisher, M.C., Flechas, S. V, Foster, C.N., Frías-Álvarez, P., Garner, T.W.J., Gratwicke, B., Guayasamin, J.M., Hirschfeld, M., Kolby, J.E., Kosch, T.A., La Marca, E., Lindenmayer, D.B., Lips, K.R., Longo, A. V, Maneyro, R., McDonald, C.A., Mendelson, J., Palacios-Rodriguez, P., Parra-Olea, G., Richards-Zawacki, C.L., Rödel, M.-O., Rovito, S.M., Soto-Azat, C., Toledo, L.F., Voyles, J., Weldon, C., Whitfield, S.M., Wilkinson, M., Zamudio, K.R., Canessa, S., 2019. Amphibian fungal panzootic causes catastrophic and ongoing loss of biodiversity. Science (80-. ). 363, 1459 LP-1463. https://doi.org/10.1126/science.aav0379

 

Update from Release trial Research at Centro Mamoni

Blake Klocke, a student at George Mason University is studying where frogs go once we release them, how long it takes them to contract the chytrid fungus, if there are any effects of releasing chytrid susceptible frogs on the existing frog community & what other non chytrid fungus sources of mortality might affect reintroduction work.

In addition to our primary project partners the Houston Zoo, Zoo New England and the Cheyenne Mountain zoo we thanks the National Geographic Society, Mohammed Bin Zayed Species Conservation Fund, and the Smithsonian Women’s Committee for their support of these release trials.

Defying disease: Panama’s frogs are fighting back

Many infectious diseases can fade away after initial outbreaks. Bubonic plague, cholera, and influenza are examples from recent human history. The same phenomenon occurs for wildlife diseases as well. How does this happen? One popular explanation is that the pathogen evolves to become less deadly, so that it doesn’t completely wipe out its hosts, ensuring pathogen survival. While this scenario does sometimes play out, we know that there are other reasons why the severity of diseases can change over time.

Cori Richards and Jamie Voyles

For amphibians, we’ve known about a highly lethal disease called “chytridiomycosis” since the 1990s. This disease was especially devastating in Central America, where it may have wiped out entire species. In this study, we made the exciting discovery that some amphibian species – frogs that were thought to be extinct – are persisting, and even recovering, after lethal disease outbreaks. We wanted to understand how it was happening. Was it a change in the pathogen, the frogs, or both?

To answer these questions, we did two things. To begin with, we surveyed frogs in Panama before and after the disease outbreak. In addition, we collected samples of the pathogen at multiple time points: during initial outbreaks and ~10 years later. We found that nearly a decade after the outbreak, the pathogen was just as deadly. However, the frogs are surviving and have better defenses against it. Panama’s frogs are fighting back! Understanding how amphibian communities are recovering after this disease outbreak is important multiple reasons. First, resolving how this works will help us develop more informed conservation strategies to protect amphibians from disease-induced extinctions. Second, clarifying how disease outbreaks subside will help us predict, and respond to, other emerging pathogens in plants, wildlife, and in humans. These goals are increasingly important in a time when rapid globalization has increased the introduction of pathogens to naïve host populations.

Atelopus varius is one species that appears to have evolved antifungal skin secretions

by Jamie Voyles and Cori Richards-Zawacki

Read the paper: Shifts in disease dynamics in a tropical amphibian assemblage are not due to pathogen attenuation BY JAMIE VOYLES, DOUGLAS C. WOODHAMS, VERONICA SAENZ, ALLISON Q. BYRNE, RACHEL PEREZ, GABRIELA RIOS-SOTELO, MASON J. RYAN, MOLLY C. BLETZ, FLORENCE ANN SOBELL, SHAWNA MCLETCHIE, LAURA REINERT, ERICA BREE ROSENBLUM, LOUISE A. ROLLINS-SMITH, ROBERTO IBÁÑEZ, JULIE M. RAY, EDGARDO J. GRIFFITH, HEIDI ROSS, CORINNE L. RICHARDS-ZAWACKI SCIENCE 30 MAR 2018 : 1517-1519

The Smithsonian Tropical Research Institute and Panama’s Ministry of the Environment (MiAmbiente) Participate in Frog Release Trials in Eastern Panama as Part of the Implementation of the Action Plan for the Conservation of Amphibians in Panama

Scientists from the Smithsonian Tropical Research Institute (STRI) and officials from Panama’s Ministry of the Environment (MiAmbiente) visited the Mamoní Valley Reserve, where release trials are underway to release Limosa Harlequin (Atelopus limosus) frogs. These frogs were bred in captivity and are the descendants of frogs collected a few years ago in the same area.

MiAmbiente was represented by biologists Erick Núñez and Anthony Vega, technicians from the Department of Biodiversity of the Office of Protected Areas and Wildlife. They were accompanied by STRI staff scientist Roberto Ibáñez, director of the Panama Amphibian Rescue and Conservation Project (PARC), and Juan Maté, STRI’s manager for scientific affairs and operations and institutional liaison with MiAmbiente. PhD student at the Smithsonian-Mason School of Conservation at George Mason University, Blake Klocke, who is currently conducting this research, hosted and guided this visit, together with his field assistant, Mirjana Mataya.

Some of the frogs are from the initial release trial conducted in the El Valle del Mammoní Reserve by Panamanian PhD students from Virginia Tech, Daniel Medina and Angie Estrada. They kept the frogs inside enclosures in this reserve to protect them from predators and so that they could obtain samples to determine if they were infected by the chrytrid fungus (Batrachochytrium dendrobatidis). In a second release trial, Blake Klocke freed these and additional frogs. In this phase of the investigation, one of the objectives is to determine if it is necessary to keep in enclosures before releasing them completely. Some of the frogs were equipped with radio transmitters that allow researchers to follow their movements and estimate the size of their territories.

The visit with MiAmbiente officials was aimed at monitoring the release trials and the progress of research. Blake Klocke showed them how the radio-telemetry tracking system works using mini-transistors. This technological tool, applied to scientific research, allows us to follow the movements of these small frogs. Frogs without radio transmitters were certainly harder to observe. Likewise, measurements of the size and weight of frogs were obtained and samples of their skin were collected with swabs for detection of the chytrid fungus. At this point, the frogs have been kept close to the point of release. However, based on the data being collected, researchers will be able to estimate the future dispersion and survival of the frogs.

The initiative to advance the release trials is part of the Panama Amphibian Rescue and Conservation Project, known colloquially as PARC and administered by the Smithsonian Tropical Research Institute under the supervision of MiAmbiente. This project is a collaboration among several organizations including Cheyenne Mountain Zoo, Houston Zoo, Smithsonian National Zoological Park and New England Zoo. It has been supported by a long list of sponsors, among them Minera Panama SA.
PARC has two facilities, one at El Níspero Zoo in El Valle de Antón, Coclé, now known as PARC El Valle and the other in Gamboa in the Panama Canal Watershed, known as PARC Gamboa. The PARC El Valle facility received the first rescued frogs, which had been temporarily kept at the Hotel Campestre in 2007, an initiative of the El Nispero Zoo and the Houston Zoo, with funding from the latter as an emergency response to the reduction in numbers of amphibians due to the mortality caused when the fungus arrived in El Valle de Antón in 2006. In 2009, this facility in El Valle came under the umbrella of the PARC project, and has continued its operation within the El Níspero Zoo. In addition, in 2009, PARC Gamboa initially began with the building of facilities at Summit Municipal Park, before relocating to its current location in Gamboa in 2012 to improve and expand capacity for ex-situ conservation of amphibians and create an additional backup at a second site. The PARC project is characterized by the result of the joint effort of multiple organizations and large numbers of people who, over the years, have contributed to the conservation of Panama’s amphibians.

MiAmbiente and the STRI have an inter-agency collaborative agreement under which they work closely on the implementation of the Amphibian Conservation Action Plan in Panama approved in 2011. The Plan aims to ensure the conservation of amphibian populations through the implementation of actions that promote research and management, both in situ (in their habitat) and ex situ (outside their habitat) in addition to promoting the education of society in general. This plan integrates specific research, conservation and education activities in the short and medium term with the goal of safeguarding our natural heritage.

This visit served as a joint verification by STRI and MiAmbiente on the progress of the project. An important milestone has been reached in the implementation of this Action Plan, as this is the first time in Panama that an amphibian conservation project is executing the phase where the behavior and survival of frogs reared in captivity is being investigated by exposing the animals to their natural environment. The results of these release trials will be of great use in guiding future efforts to re-establish the populations of certain species of frogs at sites where they have decreased in abundance or disappeared.

Earth optimism: Frogs

What’s Working in Conservation

The global conservation movement has reached a turning point. We have documented the fast pace of habitat loss, the growing number of endangered and extinct species, and the increasing speed of global climate change. Yet while the seriousness of these threats cannot be denied, there are a growing number of examples of improvements in the health of species and ecosystems, along with benefits to human well-being, thanks to our conservation actions. Earth Optimism is a global initiative that celebrates a change in focus from problem to solution, from a sense of loss to one of hope, in the dialogue about conservation and sustainability.

The Smithsonian will host an Earth Optimism Summit in Washington DC April 21-23, 2017
Please register if you are coming in person or stream the presentations online here: https://earthoptimism.si.edu/calendar/summit Sunday is a free public day.

Dr Brian Gratwicke will present the Panama Amphibian Rescue and Conservation Project on Saturday April 22 5:15pm on the panel Science on the Edge

Science to the Rescue in the #FightForFrogs

Gina Della Togna with a Panamanian golden frog, a beloved species at the center of her research. (Photo by Pei-Chih Lee, Smithsonian Conservation Biology Institute)

Gina Della Togna with a Panamanian golden frog, a beloved species at the center of her research. (Photo by Pei-Chih Lee, Smithsonian Conservation Biology Institute)

When SCBI conservation biologist Brian Gratwicke started the Panama Amphibian Rescue and Conservation Project with partners in 2009, it was a mad dash to find and collect frogs representing the very last best hope for their species, rapidly vanishing at the hands of an amphibian chytrid fungus (Batrachochytrium dendrobatidis, or Bd) that causes a disease called chytridiomycosis.

If that was the opening chapter of the rescue project’s story, seven years later the story reads like a manuscript for an initiative set up to be among the most successful comprehensive conservation projects to date.

Today the rescue project has provided a stable safe haven for 12 of the most imperiled Panamanian frog species, requiring keepers to learn the complex husbandry, behavior and reproductive physiology unique to each individual species. In the meantime, rescue project scientists are making strides in developing and refining assisted reproduction protocols, while also conducting experiments in a resolute search for a cure for Bd.

“We are entering a new phase,” Gratwicke says. “We’ve brought together some of the world’s leading animal husbandry experts, veterinarians, reproductive biologists, disease ecologists and herpetologists. With all of the talented scientific minds working on this one, we have great hope that we may someday be able to return these species safely to their home in the wild.”

Searching for a Cure

Things in Matt Becker’s lab can sometimes get a bit…strange. Take, for instance, an experiment the SCBI postdoctoral researcher conducted a year ago with unexpected results. Becker’s research focuses on the use of probiotics—or beneficial bacteria—to help frogs fight off Bd. Last year Becker applied five different probiotics with anti-fungal properties to the skin of five groups of Panamanian golden frogs, hoping to discover which probiotic gives them an effective shield against the pathogen.

Matt Becker prepares-probiotic baths. (Photo by Brian Gratwicke)

Matt Becker prepares-probiotic baths. (Photo by Brian Gratwicke, Smithsonian Conservation Biology Institute)

What he found surprised him. In past experiments, the probiotics were ineffective and all of the frogs died after the researchers infected them with Bd. This time, though, about 25 percent of the individuals survived. And those surviving frogs didn’t come from just one group with one kind of probiotics, but from every group, even the one that had been infected with Bd without a probiotic protectant.

So Becker and Gratwicke needed to determine what it was that the frogs did have in common to help them fight the disease. They started by looking at the frogs’ microbial community, or the complex community of bacteria on the skin. All of the frogs that survived had a greater abundance of specific bacteria on their skin.

In June of this year, the team launched a new experiment, this time using frogs from the Species Survival Plan collection at the Maryland Zoo in Baltimore that have similar abundances and types of bacteria as those that survived last year. The researchers have given the frogs a cocktail of eight bacteria that seem to strongly ward off Bd.

Looking at which immune system genes turn on or off to fight off a chytrid infection can help scientists discover why some frogs aren't as susceptible. (Photo by Mehgan Murphy, Smithsonian's National Zoo)

Looking at which immune system genes turn on or off to fight off a chytrid infection can help scientists discover why some frogs aren’t as susceptible. (Photo by Mehgan Murphy, Smithsonian’s National Zoo)

“At the start of every experiment, you’re really optimistic,” says Becker, who has been working on golden frog probiotics since 2007. “It’s been a great journey and we’re really learning a lot about golden frogs and how chytrid affects these guys. Every little bit of information really goes a long way for the conservation of this species and similar species.”

For the first time during a probiotics study on frogs, the researchers will also be looking at the gene expression—or combination of genes in an individual frog that gets turned on or turned off—while the frog mounts an immune response to fight off Bd.

“We’re throwing everything we’ve got at this,” Becker says. “We want to be able to use these tools to determine which frogs in the overall captive population share those same strengths—either their microbial community or gene expression—that keep them alive. There are so many questions we need to answer, but through the scientific process, we’re getting there.”

Frogs for the Future

While Becker is focused on getting frogs safely back into the wild, this goal is only possible if there are actually future generations of frogs to release into the wild. That’s where Smithsonian researcher and Panamanian native Gina Della Togna comes in.

Gina Della Togna in the lab. (Photo by Brian Gratwicke)

Gina Della Togna in the lab. (Photo by Brian Gratwicke, Smithsonian Conservation Biology Institute)

Della Togna is working on a number of complex assisted reproduction techniques for Panamanian frog species. She is the first scientist to develop protocols for extracting and freezing sperm from the Panamanian golden frog, a species that is extinct in the wild and a cultural icon in her home country. Scientists could someday use the sperm to infuse populations with additional genetic diversity, key to a species’ overall health.

“When we started, we didn’t know anything about anything,” Della Togna says. “We needed to learn which hormones at what concentrations to use, how to keep the sperm alive long enough to freeze it and the best techniques to freeze it so that the sperm is viable when we thaw it, even years later. It was a challenge, but I love a good challenge.”

Now Della Togna is working on developing similar protocol for other rescue project species, including the mountain harlequin frog, Pirre harlequin frog, variable harlequin frog, limosa harlequin frog and the rusty robber frog. In the future, she plans to get out into the field to capture genetic lineages from frogs in the wild. As she continues to perfect these protocols, Della Togna also aims to collect eggs from female Panamanian golden frogs to use for artificial fertilization with the frozen sperm. And most recently in Panama, she successfully applied a hormone treatment to help six pairs of the limosa harlequin frog and Pirre harlequin frogs breed that hadn’t laid eggs before.

“Breeding frogs is the fundamental step to sustaining captive populations and growing the numbers for release trials,” Gratwicke says. “Gina’s work is of huge applied value to us because we have some very challenging species to breed, and hormone dosing may help us to get them to cycle reproductively, even if we can’t figure out the external reproduction cues.”

For Della Togna, Gratwicke and Becker, the goal is the same: to give these unique species a fighting chance against Bd.

“If these frogs go extinct, nothing can replace them,” Della Togna says. “They are important to the ecosystem and essential to our planet’s equilibrium. There’s no doubt that we’re responsible for getting them back to where they belong.”

From now until the end of August, you can help us #FightForFrogs! Our generous sponsor Golden Frog—a global online services provider with a terrific name—will match donations to the rescue project up to $20,000, helping us raise money critical to our fight for frogs. Your donations during the Fight for Frogs campaign will buy us equipment to care for the frogs in the rescue pods, help us continue to conduct experiments to find a cure, ensure crucial breakthroughs, and ultimately one day see the return of these incredible species to their home in the wild.

The Panama Amphibian Rescue and Conservation Project is a project partnership between the Cheyenne Mountain Zoo, the Houston Zoo, Zoo New England and Smithsonian Institution. You can follow the Fight for Frogs campaign on Twitter using the #FightForFrogs hashtag or on the rescue project’s Facebook page.

Join us as together we Fight for Frogs

Brian swabs frogs in the field_Brian GratwickeFrogs matter. As a kid in nursery school, I remember observing tadpoles metamorphose into froglets right before our eyes in the classroom. It was like watching a magic trick over and over again. As I grew more interested in these cool little creatures, I learned that some frogs reproduce using pouches, others by swallowing their own eggs and regurgitating their young, others still by laying eggs that hatch directly into little froglets. It was like discovering not one magic trick, but an entire magical world—except this world was no illusion, it was real. My formative experiences both in the classroom and out rummaging around cold rainy ponds at night with my best friend and a headlamp spurred me into a career in the biological sciences. They also instilled in me a deep appreciation for the incredible diversity of life.

Panamanian golden frog_Brian GratwickeToday I am focused on conserving that incredible diversity specifically among amphibians in Panama, which is home to an astounding 214 amphibian species. Or at least it was. When a deadly amphibian chytrid fungus swept through, nine species disappeared entirely, including the country’s national animal, the beautiful Panamanian golden frog.

graphical abstractSince 2009, the Panama Amphibian Rescue and Conservation Project has spearheaded efforts to bring at-risk species into rescue pods to ride out the storm while we work on finding a cure. We’ve worked with partners to conduct several experiments in search of a cure and to better understand why some frogs resist infection and others do not. We have built new facilities that house highly endangered species of amphibians as part of a bigger global push to create an “Amphibian Ark.” These efforts and those of our colleagues around the world give me profound hope for our amphibian friends.

But we need your help.

Although frogs are the orchestral backdrop to every pond and forest, frogs have no voice to represent themselves, and they certainly can’t write checks. It’s up to professional conservationists, including the rescue project’s 12 talented conservationists in Panama, to save frogs so that others can enjoy them. This, however, requires money. From now until the end of August, our generous sponsor Golden Frog—a global online services provider with a terrific name—will match donations to the rescue project up to $20,000, helping us raise money critical to our fight for frogs. Your donations during the Fight for Frogs campaign will buy us equipment to care for the frogs in the rescue pods, help us continue to conduct experiments to find a cure, ensure crucial breakthroughs, and ultimately one day see the return of these incredible species to their home in the wild.

Together, let’s make a stand. Together, let’s #FightForFrogs.

The Panama Amphibian Rescue and Conservation Project is a project partnership between the Cheyenne Mountain Zoo, the Houston Zoo, Zoo New England and Smithsonian Institution. You can follow the Fight for Frogs campaign on Twitter using the #FightForFrogs hashtag or on the rescue project’s Facebook page.

New Amphibian Study Helps Smithsonian Scientists Prioritize Frogs at Risk of Extinction

graphical abstractScientists at the Smithsonian Institution and partners have published a paper that will help them save Panamanian frog species from extinction due to a deadly fungal disease called Chytridiomycosis (chytrid). The study, which was published Jan. 4 in Animal Conservation, draws on the expertise of amphibian biologists and scientists the Panama Amphibian Rescue and Conservation Project to mathematically determine which frog species have the best probability of escaping extinction with the rescue project’s help.
“We don’t want to arbitrarily decide which species lives and which species don’t, nor do we want to waste our time on species that don’t need our help,” said Brian Gratwicke, co-author on the paper and international coordinator of the rescue project out of the Smithsonian Conservation Biology Institute. “This study took into account the differences in opinions among amphibian experts in Panama and found consensus in a systematic away. This has allowed us to focus on the species where we have the best chance of making a difference.”

The study also found that eight Panamanian species are likely now extinct in the wild due to disease-related declines. About 80 of Panama’s frog species were too rare for conservationists to prioritize their need for help or the likelihood of successful rescue. The new prioritization scheme, however, will allow the scientists to adapt to new information as it becomes available.

“Over the years, several frog populations—and even species—have vanished or nearly vanished from Panama,” said Roberto Ibáñez, the in-country director of the rescue project at the Smithsonian Tropical Research Institute, “Unfortunately, it is impossible to save them all through conservation programs. With this study, we can focus our limited resources on those species that we are more likely to find in the wild and breed in captivity, while we simultaneously look for a way to manage chytrid.”

Since 2009, the rescue project has been building and maintaining insurance populations of frog species susceptible to chytrid, bringing small groups into captivity to breed as the species crashes in the wild. For each of Panama’s 214 known frog species, the paper’s authors asked amphibian experts to determine the probability that: 1) the rescue project could locate an adequate founding population (20 males and 20 females), 2) the rescue project could successfully breed the species and 3) without the rescue project’s help, the species would go extinct.

While most of the rescue project’s original priority species ranked high based on the new prioritization scheme, the conservationists have already started making some changes. They have determined that the likelihood of successfully breeding La Loma tree frogs (Hyloscirtus colymba) is low and they are instead shifting resources to the recently discovered Craugastor evanesco and the Rusty robber frog (Strabomantis bufoniformis), both of which came up as high priorities.

The Panama Amphibian Rescue and Conservation Project is a project partnership between the Cheyenne Mountain Zoo, the Houston Zoo, Zoo New England and Smithsonian Institution.

Golden frogs with unique communities of skin bacteria survive exposure to frog-killing fungus  

Chytridiomycosis is an amphibian disease that has wiped out populations of many frog species around the world, including the charismatic Panamanian golden frog, which now exists only in captivity in the United States and Panama.

Research published this week in the Proceedings of the Royal Society found unique communities of skin bacteria on golden frogs that survived chytridiomycosis. The original experiment was designed to test the idea that antifungal probiotic bacteria may be used to prevent chytridiomycosis in captive golden frogs. Approximately 25 percent of the golden frogs eventually cleared infection, but their survival was not associated with the probiotic treatment, rather it was associated with bacteria that were present on their skin prior to the start of the experiment. In fact, the probiotic antifungal bacteria did not appear to establish on the golden frog skin at all.

Study authors Matt Becker and Shawna Cikanek work to inoculate frogs with beneficial bacteriaMatthew Becker, a fellow at the Smithsonian Conservation Biology Institute who conducted the experiment as part of his PhD research at Virginia Tech University, says it is unclear why the microbes did not linger on the skin, but he thinks that the way he treated the frogs – with a high dose of bacteria for a short duration – may be part of the reason.

“I think identifying alternative probiotic treatment methods that optimize dosages and exposure times will be key for moving forward with the use of probiotics to mitigate chytridiomycosis,” Becker said.

Brian Gratwicke, amphibian conservation biologist at the Smithsonian Conservation Biology Institute where the experiment was conducted, says that he was disappointed that they did not find a ‘silver bullet’ to cure chytridiomycosis in this species, but noted that the results do advance our understanding of this disease.

“Previous experiments found that golden frogs are highly susceptible to chytridiomycosis, so any survival is cause for hope,” said Reid Harris, director of disease mitigation at the Amphibian Survival Alliance. “The tricky piece is figuring out the survival mechanism, and this exciting research gives some new insights in that direction.”

This research also provides additional support for the importance of symbiotic microbes, or the ‘microbiome,’ for the health of their hosts, ranging from sponges and corals to humans.

“In all multi-cellular organisms, we have suites of microbes performing critical functions for their hosts, and the same appears to be true for golden frogs,” said Lisa Belden, who supervised the study at Virginia Tech University.

The team, led by Becker, now plans to determine if this study is repeatable by investigating whether the golden frog’s skin microbiota can predict the susceptibility to chytridiomycosis. They will also investigate whether the bacteria associated with the surviving frogs from this study can be used as a probiotic treatment to prevent infections of golden frogs without a ‘protective’ microbiota.

“The ultimate goal of this research is to identify a method to establish healthy populations of golden frogs in their native habitat, despite the presence of chytridiomycosis in the environment,” Becker said.

Citation: Matthew H. Becker, Jenifer B. Walke, Shawna Cikanek, Anna E. Savage, Nichole Mattheus, Celina N. Santiago, Kevin P. C. Minbiole, Reid N. Harris, Lisa K. Belden, Brian Gratwicke (2015) Composition of symbiotic bacteria predicts survival in Panamanian golden frogs infected with a lethal fungus. Proc. R. Soc. B: 2015 282 20142881; DOI: 10.1098/rspb.2014.2881. Published 18 March 2015