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

The Amphibian Pet Trade: Good for Business, Bad for Biomes?

Tree frogs are among the popular amphibian species kept as pets. (Photo by Brian Gratwicke, Panama Amphibian Rescue and Conservation Project)

How many times have you walked into a pet store and been surprised by the variety of amphibians available for purchase? I tend to gawk, awestruck, at these amazing creatures, just as though I’m admiring them during a visit to the zoo: Pacman frogs, White’s tree frogs, Malayan leaf frogs, powder blue poison arrow frogs, the list goes on…and all of these are available to buy. Many of these species are exquisite, exciting, beautiful and definitely non-native to the U.S. of A. But as much as we may love frogs and want to keep them as pets, we have to consider whether taking in such a pet has conservation implications.

The term “exotic” calls to mind word associations like “foreign” and “interesting,” which are not necessarily bad words, but certainly indicate something beyond the garden variety of whatever it is that we are comparing, be they automobiles, eggplants or footwear. With regards to organisms, however, “exotic” can mean something a little more problematic. Exotic, or introduced, species are defined by the National Park Service as “those that occur in a given place as a result of direct or indirect, deliberate or accidental actions by humans.”

If introduced to an environment, a non-native species can become an invasive species, outcompeting native species. For instance, it is quite likely that the Burmese pythons now prevalent in the Florida Everglades were initially kept as pets and became invasives upon their intended or accidental release, adapting quickly to environments similar to their own Amazon estuaries and southeast Asian swamps, respectively. Adaptations like high reproductive rates, longevity and the ability to consume large prey, combined with their misplacement, can allow them to outcompete and often consume native species like American alligators, opossums and even great blue herons, according to an article published in the Wilson Journal of Ornithology.

A few particularly popular amphibian species that might not have quite the same effects as their serpentine kin–but are just as exotic—include the tomato frog and the well-known families of Dendrobatidae (poison dart frogs) and Hylidae (red-eyed tree frogs and spring peepers, to name two). These particular amphibians are regulated by the Convention on International Trade in Endangered Species of Wild Fauna and Flora, or CITES, which establishes controls, protocol and limits for managing species that are endangered in the wild but for which there is high consumer demand. These frogs are listed among either the first or second appendices of CITES, meaning that they are restricted from being captured in the wild or are threatened in the wild, and their trade or sale may be regulated or restricted at any time. However, captive-bred individuals of these species are acceptable for trade and sale. Pets that are illegal to own generally depend on state laws, and many states have clear laws discussing what animals are illegal to be kept as pets and which animals require a permit to keep. For instance, the state of New Jersey requires a permit to own African clawed frogs, red-eyed tree frogs and a variety of other common pet trade frogs.

The quality and conduct of the facilities that breed and supply these amphibians should be assessed by the consumer prior to purchasing, according to Ed Smith, a biologist at the Smithsonian’s National Zoo. The amphibian pet trade is thought to be contributing to declining amphibian populations in the wild by overharvesting wild rare species and may play a role in spreading diseases. While the over collection of restricted range amphibians has contributed greatly to population decreases, habitat destruction and a species’ natural confinements can also negatively affect its survival rates. If you are considering investing in an exotic species, please be sure of two things. First, that the amphibian you are purchasing is not an illegal species prohibited by CITES. Second, that the farm or source has raised or procured the frog sustainably and in accordance to the best husbandry practice. Simply because a species can be traded does not necessarily mean that it is okay to purchase one. Do some background research on the species that you plan to purchase, not only to determine what kind of care and conditions you will need to provide your amphibious friend, but also to determine if this is a species that you can own without adversely affecting wild populations.

The Salamander Room by Anne Mazer

“The Salamander Room” by Anne Mazer discusses a young boy’s enthusiasm about keeping a salamander as a pet and how keeping the salamander changes his life literally and figuratively.

Smith advises that anyone interested in caring for amphibians read a book called “The Salamander Room” by Anne Mazer. This picture book discusses a young boy’s enthusiasm about keeping a salamander as a pet and how keeping the salamander changes his life literally and figuratively.

“Like the boy in the story who models his room after the salamander’s habitat, we often find that fascination with one thing becomes a window to a world of further amazement,” Smith said. “Wanting to provide his salamander with everything it needed, the boy in the story considered each element of its habitat, one clump of moss and decomposing log at a time, until he had re-created the forest itself. There is something about the keeping of an aquarium or terrarium that leads conscientious caretakers to appreciate the details of an ecosystem—the essence of such an enterprise, or hobby, is caring.”

So before you run down to the pet store or queue up that pet distributor’s website, consider these parting thoughts from Ed Smith:

Two basic questions to ask when purchasing an amphibian (or any pet): “Can you care for it well? Are you harming amphibians at large with this purchase?”

Should you buy captive-bred or wild-caught amphibians for pets? “Consider captive-bred first (meaning animals that are already acclimatized, disease-free and not diminishing wild populations).”

Motivation for investing in an amphibian: “The business of caring for living things hones our focus to allow us to appreciate their complexities and hopefully enables us to better appreciate the diversity of plants and animals in the wild.”

Phil Jaseph, Smithsonian’s National Zoo

REPORT from Defenders of Wildlife: Perils Of The Frog Leg Trade

American bullfrog (Rana catesbeiana)

The frog leg market is systematically devastating frog populations throughout the world and, subsequently, causing severe environmental impacts to natural ecosystems. (Photo courtesy of the Utah Division of Wildlife Resources)

International wildlife conservation groups Pro Wildlife, Defenders of Wildlife, and the Animal Welfare Institute, issued a report in July titled Canapés to Extinction: The international trade in frogs’ legs and its ecological impact. The report is the first comprehensive study of the frog leg market ever conducted and reveals an industry that is systematically devastating frog populations throughout the world and, subsequently, causing severe environmental impacts to natural ecosystems.

“Humans have been eating frogs for ages. But today the practice is not sustainable on a global scale,” said Alejandra Goyenechea, acting director of international conservation programs for Defenders of Wildlife. “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.”

In recent years, the United States has imported an average of 2,280 tonnes (4.6 million pounds) of frog legs each year—the equivalent of 456 million to 1.1 billion frogs—and another 2,216 tonnes (4.4 million pounds) of live frogs for Asian-American markets. Most frog and frog leg imports to the United States come from China, Taiwan, Ecuador, Brazil, the Dominican Republic, Vietnam, Mexico and Indonesia.

During the last decade, the European Union imported an average of 4,600 tonnes (9.2 million pounds) of frog legs each year—the equivalent of 1 to 2.3 billion frogs. Indonesia is the world’s leading supplier, providing 84 percent of total imports to the EU with the vast majority of frogs being caught in the wild. Belgium, France and the Netherlands are the top importers in the EU.

“The decline of many frog species is a global problem that is being greatly accelerated by just a handful of European nations,” said Sandra Altherr, director of wildlife programs for Pro Wildlife in Germany. “The capture and killing of native frogs is prohibited within the EU, so it is incomprehensible that we would be supporting environmentally disastrous practices abroad.”

Until the mid-1980s, India and Bangladesh dominated the international frog leg export market. Severe exploitation resulted in the collapse of many wild frog populations in those countries, including two of the most sought-after species, the green pond frog and the Indian bullfrog. In turn, the decline of those species resulted in a dramatic increase in the use of pesticides, due to an explosion of insects and other agricultural pests previously kept in check by frogs. In 1985, the two frog species were protected with an Appendix II listing under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). India and Bangladesh subsequently banned exports, their native species have since recovered and the use of pesticides has been reduced.

However, in recent years, other countries have stepped in to fill the void and their frog populations appear to be headed for a similar fate. Indonesia, where billions of frogs are taken from the wild annually, and to a lesser extent China, Taiwan and Vietnam, where frogs are farmed very intensively, have now taken over the export market.

“We must take immediate action to protect frog species from being exploited for international trade,” said D.J. Schubert, a wildlife biologist with the Animal Welfare Institute. “Wild populations across Asia are already in trouble, and unregulated trade puts native species in the U.S. at even greater risk from deadly diseases that have been wreaking havoc on amphibians worldwide. It will take a coordinated effort from governments and the world’s conservation community to prevent the extinction of imperiled frog species and to protect our native species from harmful invasives.”

The report will be distributed to key government decision-makers, including those responsible for the implementation of CITES, with a request that they take immediate action to bring this unregulated trade under control.  Considering that the frog species dominating the frog leg trade are not currently protected under CITES, there is an urgent need for governments to secure CITES protections for them.

Download the full report

Read Scientific American’s coverage of this report.

The Hidden Jewels of Appalachia

 

“The Hidden Jewels of Appalachia” is a short film that uses compelling imagery to showcase Appalachia and raise awareness for declining Appalachian salamanders.  The Appalachian region of the eastern United States features an ancient mountain chain that serves as the world’s epicenter for salamander biodiversity.  These secretive creatures, ranging in size from two inches to more than two feet, are a keystone species at risk from a perfect storm of threats, including: development, climate change, mountaintop mining, invasive species, disease, transportation corridors, acid rain, pollution, and more.  Learn what these declining “canaries in the coal mine” are telling us about the state of our environment.

The Smithsonian Conservation Biology Institute is working to become a leader in salamander conservation through innovative research looking at Plethodon species competition and climate change affecting the eastern hellbender (Cryptobranchus alleganiesis), as well as working to connect people to their local environment through public presentations, conducting field surveys and swabbing salamanders for disease.  For more information, please find Appalachian salamanders on Facebook.

–Joe Milmoe, U.S. Fish and Wildlife Service.

Cute Frog of the Week to feature ARKive’s cutest frogs

Riobamba marsupial frog  (Gastrotheca riobambae)

This image of a Riobamba marsupial frog is ARKive Research Manager Dr. Verity Pitts' favorite frog photo in the ARKive collection. (© Pete Oxford / naturepl.com)

Every Monday morning we enjoy sharing with you a particularly adorable amphibian photo, complete with fun facts through our popular Cute Frog of the Week feature. Now, thanks to ARKive–a website containing an extensive collection of photos, videos, facts and updates about endangered species from all over the world–we’ll have even more diverse library of captivating images to share with you. We love that ARKive is helping educate individuals globally through images and wanted to share a Q&A we conducted with Dr. Verity Pitts, one of ARKive’s research managers a senior team member.

1. What was the primary objective for beginning ARKive? Now that it has become such a large site, has this objective changed?

ARKive was launched in 2003 and is an initiative of the international charity Wildscreen.

Wildscreen’s mission is to promote a greater understanding of the natural world, and the need for its conservation, using the emotive power of the very best wildlife films and photos.

A brainchild of the late Christopher Parsons OBE, former Head of the BBC Natural History Unit, and one of Wildscreen’s founders, ARKive was, and still is, a centralized multi-media library of the world’s endangered species.

ARKive not only communicates the wonders of the planet’s biodiversity, but it also provides a safe haven for almost 100,000 film clips and photos–for use by today’s generation and those of the future.

The ethos of ARKive remains true to its origins: providing unrivaled access for people from around the world to amazing imagery, unlocking the wonders of the natural world, in a bid to protect the planet’s precious flora and fauna.

2. What do you think that films and photos can uniquely do for conservation that other actions may not be able to accomplish?

Wildscreen’s Patrons have answered this question very eloquently:

“Natural history films are more than just entertainment. They provide a crucial insight into the world, from which so many of us are increasingly divorced. We cannot properly value what we do not know. I truly believe the films that Wildscreen cares for and promotes are major elements in the battle to protect our imperilled natural world.”
Sir David Attenborough, world-renowned naturalist and broadcaster

“Books and lectures can do a lot to explain the facts of life on this planet, but films and photographs are better at stirring the imagination.”
HRH The Duke of Edinburgh

3. What kind of audience does ARKive hope to reach? How does this affect the content that it hosts or shares?

Through ARKive, Wildscreen’s mission has always been to provide people from all walks of life free access to its amazing collection of educational and awe-inspiring content.

Wildlife imagery can be a powerful tool in the fight to combat biodiversity loss and to reconnect people with nature–no matter how young or old. ARKive reveals what species look like, what makes them special and why we should care. Whether in the classroom or lecture hall, at home or in the field, ARKive transcends boundaries, and can be used in numerous educational situations–both formal and informal.

We do tailor information for different audiences, and on ARKive visitors can explore content in lots of different ways–through scrolling galleries of stunning images; by habitats; countries and topics, such as climate change; to fun interactive games and activities.

The ARKive blog is a relatively new feature to ARKive, but it enables us to use the ARKive imagery in different ways, helping us: tell stories about threatened species in the news; publish featured articles; update our visitors with what’s new to ARKive; as well as entertain with quizzes and games.

4. We’re so grateful that you’re helping us out with our Cute Frog of the Week. How has ARKive been able to work with and promote conservation organizations like ours?

Wildscreen recognizes the importance and value of building relationships and works in partnership with organizations from around the world on many different levels.

We believe that heightened public awareness to conservation issues translates into action, campaigning, lobbying and fundraising–all vital for protecting our most endangered species and habitats.

Through ARKive, Wildscreen is able to promote and support the efforts of conservation organizations working on the ground in a bid to save a huge variety of species.

5. ARKive has worked in cooperation with the Smithsonian and Google Earth. What future projects or objectives does Wildscreen hope to accomplish?

Reaching new audiences and engaging more people with the importance of biodiversity is an ongoing priority, whether this is by developing new resources and activities, via outreach programmes and new technologies, or of course through partnership working.

Wildscreen will continue to build on current partnerships and encourage new collaborations to enable additional access to ARKive through multiple third party platforms to reach even greater audiences.

6. What type of reaction do you hope that visitors to ARKive’s site have when browsing through the images?

Wildscreen’s aim is to open the window onto the natural world through its ARKive project. The charity works with the world’s finest photographers, filmmakers, scientists and conservationists to bring scientific names to life.

By inspiring people to care for the natural world and its many wonders, Wildscreen hopes to motivate visitors to become involved in the conservation movement, whether on a local or global level.

7. What do you enjoy most about the work you do at ARKive?

There are now more than 75,000 photos on the ARKive website and each of these has been hand-picked by one of our researchers. We only select the ‘best’ images for each species, which are either engaging portrait shots or shots that tell the story of the species’ life history. However, for some species only a few images exist and tracking these down is a very rewarding task.

Having worked on the ARKive project for nearly eight years, I still enjoy learning about new species and seeing the stunning imagery that is pouring into the office from around the world.

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.

# # #

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

This time, it is not good to be a leader

Atelopus varius

Atelopus varius is just one of many species of frog that is critically endangered. (Photo by Brian Gratwicke, Panama Amphibian Rescue and Conservation Project).

Chytrid fungus is believed to have played a role in the disappearance of 94 of the 120 frog species thought to have gone extinct since 1980.  But that is not the only battle frogs are facing in the fight to survive.

No one issue can explain all of the population declines that are occurring at an unprecedented rate, and much faster in amphibians than most other animals, the scientists conclude in a study just published in the Annals of the New York Academy of Sciences.

The totality of these changes leads these researchers to believe that the Earth is now in a major extinction episode similar to five other mass extinction events in the planet’s history. And amphibians are leading the field – one estimate indicates they are disappearing at more than 200 times that of the average extinction rate.

In this case, it is not good to be the leader.

Cindy Hoffman, Defenders of Wildlife

A sad story with a golden glimmer of hope

Panamanian golden frog (Atelopus zeteki)
Panamanian golden frog (Atelopus zeteki)

Cute Frog of the Week: May 2, 2011

Critically endangered since 2004, the endemic Panamanian golden frog has suffered a population decline of 80 percent over the last 10 years. An angular, dark yellow frog with a trademark swagger, the golden frog is a symbol of Panama’s abundant biodiversity. It is also well-known for its potent skin toxins, which it uses to protect itself against predators. A single frog’s skin contains enough nerve-disabling poison to kill 1,200 mice! Frequently found in and around high mountain forest streams, the golden frog in its golden-yellow, liberally spotted morph (individuals come in various colors and patterns) visually warns potential predators to stay away.

Despite its toxicity, the frog has found itself nearly defenseless against chytridiomycosis, the amphibian disease epidemic that has recently devastated frog populations and biodiversity throughout Central America. Because the range of this frog species is limited, extinction seems all too likely, unless human intervention succeeds in keeping the species around in captivity. Fortunately, an in-situ conservation program in western Panama (the El Valle Amphibian Conservation Center, aptly named EVACC) has led the conservation effort as part of the Panama Amphibian Rescue and Conservation Project.

Frog declines raise a number of fascinating questions.  For example, recent studies have shown that Panamanian golden frogs are making a last-ditch attempt to ward off infection by thermally killing the pathogen. Fortunately, researchers believe that the chytrid fungus does not thrive at temperatures 5 C above the frog’s normal body temperature. The frog attempts to increase its body temperature above normal levels by moving within its habitat to warmer places. As an ectotherm (a cold-blooded animal), the frog can only control its internal temperature by these behavioral adjustments to its external environment. Nonetheless, these efforts by wild golden frog populations may by in vain. Chytridiomycosis has so far prevailed, but intense conservation efforts in Panama keep hope alive. Panama’s symbol of amphibian beauty continues to awe humans in safe environments like EVACC. Re-introduction of these individuals and any offspring into the wild will, we are assured, only take place if and when the epidemic has abated.

Photo credit: Mehgan Murphy, Smithsonian’s National Zoo

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: http://www.flickr.com/groups/cutefrogoftheweek/

Notes from the Field: Finding the Limosa harlequin frog

Jenyva Turner, Cheyenne Mountain Zoo animal keeper

Jenyva shows off an Atelopus limosus the Cheyenne Mountain Zoo team captured during the February expedition. (Photo courtesy of the Cheyenne Mountain Zoo)

Wanted: Adventurous expedition members to hike into the jungles of Panama looking for the rare Atelopus limosus. Must be willing to hike long hours in rugged, muddy terrain and in thigh-deep water, and ready to be wet, hungry, tired, and not afraid of spiders, snakes, scorpions, and lots of insects.

SIGN ME UP!!!

How could I pass up an opportunity to hike, explore, and camp in the jungle, all while helping save a species? This February was my first trip to Panama, however I followed the blog posts from other Cheyenne Mountain Zoo team members during previous expeditions to Panama, so I felt like I had already been there. I knew it was going to be a challenging trip, both physically and mentally. Would we find frogs? That was my biggest concern. As we all know, the chytrid fungus is taking its toll on frog populations around the world and the rare Atelopus limosus is not immune to chytrid’s deadly sting.

Atelopus limosus was our target species since the Panama Amphibian Rescue and Conservation Project only had one female and four males in captivity. The future of the species appeared to depend on our findings. It was the “dry season” in Panama (although, being from Colorado, rain every day does not seem very “dry”!) and therefore, was the best time to find females, as they would be coming down to the streambeds to lay their eggs. The males would be there waiting.

We hiked along the stream and carefully searched the moss-covered rocks for the small, highly camouflaged black and green frogs. It was tough to be quiet and sneak up on our target as we sloshed around streambeds, stepped over branches, and slipped on rocks. We paid especially close attention to areas of the stream where the water moved a little faster. Atelopus limosus lay their eggs in faster-moving water to reduce competition from other frog species and reduce predation. The tadpoles are specially designed with little suction cup disks on their bellies to help them hold onto the rocks and keep them from being washed away. Pretty cool!

Our team found just four Atelopus limosus during our time in the field, but we were able to give hope to the species as one of those caught was a young female. We handed off our precious cargo to the capable staff at the Summit Zoo, who take their job and role in frog conservation very seriously. They are working hard to care for and propagate many other amphibian species besides Atelopus limosus to ensure the sounds of frogs continue to be heard in the jungles of Panama.

Here’s a video of Antonia Chastain, a member of the Cheyenne Mountain Zoo team, finding out first-hand how difficult it is to catch an Atelopus limosus during the February trip:

Jenyva Turner, Cheyenne Mountain Zoo animal keeper (and first-time frog finder!)

In the Field, In Search of a Cure

Rocket frog with tadpoles

Researcher Denise Küng is using emerald glass frogs and rocket frogs (shown here with tadpoles) in Panama to see if she can develop a treatment for chytrid. (Photo by Brian Gratwicke, Panama Amphibian Rescue and Conservation Project)

What comes to your mind when you think about bacteria? They are generally feared as disease agents among humans, but they do much more than cause infections. It seems like mutualistic microbial communities are common in invertebrates as well as vertebrates. Humans, with more than 600 types of bacteria residing only in their mouth, are no exception. Several cooperating bacteria can develop biofilms and create a matrix of living cells and bacterial products, and the community structure of microbes on a host could be connected with resistance to disease. Let’s say a bacterial community is disturbed by antibiotics and its competitiveness is thus reduced, then pathogens can exploit this and establish themselves in a host.

The skin of amphibians is host to a diverse microbiota. They live in damp or aquatic habitats which are potentially pathogen-rich environments. As protection against infections, amphibians developed skin defenses, such as antimicrobial peptides secreted by glands in their skin and microbial communities with antimicrobial activity. By doing bacteria removal and additional experiments, scientists found evidence for enhanced or decreased amphibian health depending on alterations of the microbial community structure on the skin. In some amphibian species, antimicrobial peptides seem to provide protection from infectious diseases such as the fungus Batrachochytrium dendrobatidis and may help to prevent population declines.

Denise with Colostethus

Denise hopes to find a treatment for frogs in nature so they can safely coexist with chytrid. (Photo by Brian Gratwicke, Panama Amphibian Rescue and Conservation Project)

To find out more about the bacterial communities and antimicrobial peptides on the skin of amphibians, I’m currently in Panama working with the Panamanian rocket frog, Colostethus panamensis, and emerald glass frog, Centrolene prosoblepon. I’m going to look at their skin microbiota and how it changes after several weeks living in captivity. Will it stay the same or are some members of the bacterial community getting lost?

By giving some of the rocket frogs a bath in a solution with bacteria, I’m trying to increase the density of a particular bacterium on their skin. This bacterium has been shown to decrease the growth of the chytrid fungus Batrachochytrium dendrobatidis in the lab. If it’s possible to amplify its density on amphibian skin over a long period of time, this might be a possible treatment for frogs in nature to allow them to coexist with the pathogen in infected environments.

The emerald glass frogs seem to be able to survive in environments infected with Batrachochytrium dendrobatidis. They must have found a form of protection from the fungus on their skin. I am taking a closer look at the antimicrobial peptides on their skin. I also bathed them in water every day for a week and then used their skin washes to treat another group of the rocket frogs with the hope that whatever protects the glass frogs from the fungus will go in the water and from there onto the skin of the rocket frogs. Analyzing the skin swabs of the frogs in the lab will show whether this treatment changed the rocket frog skin microbiota, antimicrobial petides or both.

Denise Küng, University of Zurich