Panamanian toads may harbor a cure for Chagas disease

Panamanian toads Rhinella centralis are distinguished by their dorsal skin covered with pointed warts. They are common along the Pacific coastal areas, often in urban areas around Panama City and small towns, and form large choruses on rainy nights. The small but strongly swollen poison glands on their heads secrete a white toxic goop. This effective defense mechanism makes predators spit them out, or froth at the mouth, vomit and it may even kill them if they try to eat the toad.

Scientists working at INDICASAT, the University of Panama and STRI began screening wild frogs for substances with pharmacological potential to treat various tropical diseases. When they analyzed secretions from these toads they discovered a chemical in the poison glands called 19-hydroxy-bufalin. They found that this chemical was very potent at killing the parasites that cause Chagas disease, and that it was not very toxic to cells. Chagas disease is a neglected tropical disease that kills 10,000 people per year, and current medications used to treat the disease are not very effective, particularly in acute cases. The fact that this chemical is quite selective with low cell toxicity means it is a promising compound that make it a candidate compound to further explore as a potential way to treat Chagas disease.

Read the research here:

Rodriguez, C., Ibáñez, R., Ng, M., Spadafora, C., Durant-Archibold, A.A. and Gutiérrez, M. 2020. 19-Hydroxy-bufalin, a major bufadienolide isolated from the parotoid gland secretions of the Panamanian endemic toad Rhinella centralis (Bufonidae), inhibits the growth of Trypanosoma cruzi. Toxicon 177:89-92.

The International Festival of the Salamander @ Boquete

Salamanders are remarkably enigmatic amphibians, both due to their often-cryptic colorations and their extremely secretive lifestyles. They are nocturnal, but even at night, one can hardly call them “active”. Many species are burrowing, and barely ever come out of their moist and dark haven created by earth and fungi. Other species prefer a life in the canopy of mysterious and often nearly inaccessible cloud forests, in a world dominated by bark, moss and lichen.

Bolitoglossa compacta, a poorly known salamander occurring at the border of Costa Rica and Panama. (CC BY-NC-ND 3.0) Marcos Ponce.

Panamanian salamanders are no exception to this rule. Herpetologists that set out to find them, regularly return after their tiring night-time missions without seeing even a trace of these wonderful creatures. Local people that work and live in areas where salamanders occur sometimes don’t even know of their existence – which is exactly why a handful of Panamanian institutions decided to organize the first International Festival of the Salamander.

The Festival took place from November 1 to 3 in Boquete, located right at the border of Volcan Barru National Park. Aptly, this is the place to be if one wants to set out on a nocturnal quest to look for them. During the days, there were photographic exhibitions, stands of the organizations involved, an interactive kids corner with movies and drawings for coloring and a small T-shirt shop, hosted by a team of volunteers that where sitting on the edge of their seats to tell you about their beloved salamanders.

A pet Boa constrictor juvenile named Oscar. One of the organizations had brought Oscar along to teach kids that although they remain wild animals, snakes can be quite gentle and docile too. © Leni Lammens.

But Friday and Saturday night, things even got better: every evening from 6 to 10 p.m., there was a free guided tour by Los Naturalistas in Volcan Barru National Park, with experts knowing where exactly chances of spotting one where highest.

The tour started off at the entrance of Volcan Barru National Park, where we met with a team of tour guides and biologists, led by Dr. Abel Batista. Then we drove on for another 3 km on a bumpy gravel road, until we were at a place known for its substantial salamander population. The first and most important part of the tour consisted of disinfecting boots and equipment, to avoid spreading diseases. After all, one of the major reasons of amphibian declines worldwide is an extremely infectious fungus, Batrachochytrium sp.. While harmless to us, for many amphibian species, it causes severe skin damage, leading to death of susceptible individuals. After sterilizing our shoes, we began measuring about a dozen environmental variables; humidity, temperature, elevation, etc.. In the meantime, the guides explained a few rules: avoid touching the animals, don’t shine too bright lights directly in their eyes and don’t take pictures of them for too long and preferably without flash.

Then, we started searching. The weather was cold, but very dry, and therefore, our subjects of interest would mostly be hiding in moist places, one of the guides explained. We adjusted our strategies accordingly, looking in small holes between rocks and gently turning branches to peer underneath. We slowly walked upwards, and over the course of 20 minutes, we had only progressed about a hundred meters. When we had nearly given up, one of the guides suddenly called us further on.

Tengo una!”

We hurried on, nearly running uphill. But with a great reward waiting for us: a nearly 20 cm long, female magnificent web-footed salamander (Bolitoglossa magnifica)  was cautiously watching us from underneath her hiding place – a thick, rotting branch covered with lichen, about a meter and a half away from the road. All excited, we had to take turns to take a look from the right angle, so you could see her. We all took a few pictures, then we stopped bothering her with our flashlights and left her in peace.

A cautious female magnificent web-footed salamander (Bolitoglossa magnifica) glaring at us from her hiding place. © Leni Lammens.

We started hiking down again, all the while scanning every hole and crevice.  We passed the cars, and soon after, someone else already shouted he had found another one. This one was more difficult to see, hiding in a small hole in between rocks and loose earth. We had barely gotten to the second, when a third one was found, and soon after even a fourth and fifth!

Biologist taking photographs of a salamander (left), while a guide in the back continues searching in other holes. (right) A magnificent web-footed salamander (Bolitoglossa magnifica) that found a hiding place behind a mushroom.

Despite the unfavorable weather conditions, our evening excursion turned out to be a great success, spotting 5 individuals of the endangered magnificent web-footed salamander in less than an hour and a half. We returned tired and quite hungry, but fully satisfied nonetheless.

Los Naturalistas are currently working on a salamander-focused guided tour, which will roughly follow a similar structure as the tour we could enjoy that night. They hope to organize a lot of similar events like the International Festival of the Salamander, to further raise awareness among tourists as well as Panamanians concerning these mysterious and intriguing animals. Salamanders are facing many threats, but in protected places like Volcan Barru National Park, they are thriving.

By Leni Lamens Herpetologist, biologist and intern at the Panama Amphibian Research and Conservation center, in collaboration with the Smithsonian Tropical Research Institute and Smithsonian National Zoological Park.

By Leni Lammens

I would like to express my gratitude towards all organizing parties involved in the International Festival of the Salamander:

Action Hub+, Bioguias Panamá, Los Naturalistas, Universidad Autónoma de Chiriquí (UNACHI), Vicerrectoria de Investigación y Posgrado (VIP)

as well as to all sponsors, without which the Festival would not have been possible.

 

Strawberry poison dart frogs prefer mates that look like their parents

A new research paper published on strawberry poison dart frogs in Bocas del Torro found that one of the reasons we have polymorphism or so many different color forms within one species of frog.  Female tadpoles prefer to mate with males that have the same color as their parents (sexual imprinting), and males defend their territories more vigorously from other males that are the same color as their parents (rival imprinting). The researchers demonstrated this experimentally by using foster parents of different color forms to raise offspring, and then tested mate or rival preference of the adult offspring.

This process of sexual selection can lead to sexual isolation even in populations that live in the same places. From an evolutionary perspective this would be a rare example of sympatric speciation, or the evolution through natural selection without geographical isolation.

Read the paper here  Yang, Y., Servedio, M.R., Richards-Zawacki, C.L., 2019. Imprinting sets the stage for speciation. Nature 574, 99–102.

Golden Frog Festival Calendar of Events 2019

This is the Smithsonian calendar of events to celebrate the golden frog festival 2019 

Aug 4 12:30pm to 8:30pm Visit the amphibian rescue center in Gamboa

Aug 14 11AM-3:00pm the Q?bus science education team will visit schools in El Valle de Anton

Aug 28 6PM-8PM Rana Dorada via Argentina pub talk.

Aug 27-31 Punta Culebra family-friendly frog-themed games & educational activities.

if you are looking for information on la Dorada annual run in El Valle de Anton – visit Caminando Panama 

Update on the conservation status of Harlequin Frogs in Panama

On May 30, 2019 a special issue of the Journal Biological Conservation entitled ‘Amphibian conservation in the Anthropocene: Progress and challenges‘ Edited by Vincent Devictor, Evan Grant, Erin Muths, Benedikt Schmidt, Silviu Petrovan was published. The focus of this issue is on examples of potential solutions to the amphibian crisis that are directly relevant to, and integrated with conservation management actions.

The issue features a case study on Atelopus in Panama, updating the known historical distribution records and modeling potentially suitable habitat (below).

The paper also updates the IUCN conservation status for each Panamanian Atelopus species and the status of each of these species in captive populations, with commentary on the potential use of the captive population in research to find solutions that may be useful in restoring wild populations.

Atelopus conservation status in Panama 2019

Lewis CHR., Richards-Zawacki CL., Ibáñez R., Luedtke J., Voyles J., Houser P., Gratwicke B. 2019 Conserving Panamanian harlequin frogs by integrating captive-breeding and research programs. Biol. Conserv. 236, 180–187. (doi:10.1016/J.BIOCON.2019.05.029)

Closure of Frog Facility at the Nispero Zoo

In May 2019, the Panama Amphibian Rescue and Conservation Project closed its facility at the Nispero Zoo to streamline and consolidate its captive-breeding operations at a single location in Panama. We are very grateful to the owners of the Nispero Zoo for their support of the amphibian conservation efforts for the past12 years.  This consolidation effort is part of a long-planned strategic move to reduce the costs associated with running two separate facilities. The living collection of animals is now residing at our expanded breeding facility at the Smithsonian Tropical Research Institute in Gamboa.

PARC Gamboa

The Panama Amphibian Rescue and Conservation Project”s Gamboa Facility

As part of the transition process, STRI  transferred custodianship of a portion of the living collection to MiAmbiente who allocated these frogs to the newly formed EVACC foundation. The EVACC foundation will continue to operate independently as a non-profit organization in El Valle de Anton.

Visitors who would like to see the frogs can visit our Fabulous Frogs exhibition at the Punta Culebra Nature Center in Amador, Panama City, or at our small exhibition niche in Gamboa (8:30am – 4pm daily).

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

 

Role of Zoos and Corporations in Conserving Panamanian Amphibians

The Panama Amphibian Rescue and Conservation Project was created in 2009 as a partnership between Zoo New England, Cheyenne Mountain Zoo, Houston Zoo, Smithsonian National Zoo, Smithsonian Tropical Research Institute and Defenders of Wildlife to build captive populations of species at risk of extinction from the deadly amphibian chytrid fungus. Together we have built significant capacity for amphibian conservation in Pamama by contributing financial resources, involving zoo staff in field work to collect and care for endangered amphibians, training our Panamanian colleagues in state-of-the art animal care, veterinary care, pedigree management and record-keeping.

Since the project was established, Zoos have provided approximately $300K per year with a total investment of $2.7m in the project that leveraged additional support of $3.9m in grants from Miambiente, First Quantum Minerals (Cobre Panama), USAID, the National Science Foundation, SENACYT, National Geographic, US Fish and Wildlife Service, Mohamed bin Zayed Species Conservation Fund, the Morris Animal foundation and other private donors. First Quantum Minerals (Cobre Panama) has been our largest corporate contributor, providing approximately $450K per year with a total investment of $2.3m in the project.

Milestones

Endangered Frogs
Established founding populations of 12 species of Panama’s most endangered frogs, including Panama’s iconic Panamanian Golden Frog. Reproduced all 12 species in captivity most of them bred in captivity for the first-time ever by project staff.

Priority rescue species PARC

Capacity-Building
Constructed the Gamboa Amphibian Rescue and Conservation Center which is now the largest amphibian conservation breeding center in the world and trained a professional cadre of conservation staff to care for the animals.

PARC Gamboa

Research
Established a world-class research program investigating the frog-killing chytrid fugus and searching for a cure for the disease. Conducting hormone stimulation research to improve captive reproduction. Continued publications of veterinary care, nutrition and husbandry of amphibians to improve knowledge to sustain captive amphibians.

Reintroductions
Conducted the first-ever reintroduction trials of amphibians to learn about the limiting factors how captive frogs transition back into the wild. This data will be used to inform future release strategies using adaptive management principles.

Education
Annual coordination of ‘Festival la Rana Dorada’ activities in Panama City, continued operation of fabulous frogs of Panama exhibition and the integrated informal schools’ curriculum.

Vision for the future
We need to continue to grow the captive amphibian populations to about 300 animals per species with even representation of founder animal genes as the primary assurance colony. This core captive population will safeguard against species’ extinction, and biological banking of gametes will help to ensure against unintended genetic bottlenecks in captivity. Surplus-bred animals will be used for further basic reintroduction research, breeding for disease-resistance, finding a cure for the amphibian chytrid fungus, and basic research that will ultimately be used to reestablish viable wild populations of these species.

Spindly leg syndrome in amphibians

Spindly leg syndrome is the bane of many captive breeding efforts in amphibians, causing much speculation on husbandry boards. This syndrome results in poorly developed limbs of post-metamorphic froglets. The condition has been observed in most of the species we have reared at the Panama Amphibian Rescue and Conservation Project and its a priority for us to resolve from an animal welfare and production perspective.

Atelopus certus post-metamorphs, an example of a SLS frog with poorly developed forelimbs (left) compared with a healthy froglet from the same clutch (right).

Many people had speculated that it was related to a nutritional deficiency in tadpoles or parent frogs, but the new study from the Panama Amphibian Rescue and Conservation Project using Atelopus tadpoles found no connection to diet, but treating the water by reverse osmosis filtration and then reconstituting the minerals was a sure-fire way to reduce the incidence of this syndrome. It is possible that the filtration process removed some factor that caused the syndrome, or that the reconstitution process added minerals such as calcium that were lacking in the original tap water.

One other factor that aggravated SLS was overfeeding of tadpoles, so our future work will manipulate dissolved mineral ratios in future experimental setups. We have been awarded a grant from the Morris Animal Foundation to continue our work on this. Further isolating the factor(s) responsible for causing this syndrome, will help us to improve captive amphibian welfare and allow managers to better control production of amphibians in captive breeding efforts.

Julio working on the second experiment manipulating food quantity, water composition and diet type. Each tank contained 20 full sibling Atelopus glyphus.

Citation: Camperio Ciani JF, Guerrel J, Baitchman E, Diaz R, Evans M, Ibáñez R, et al. (2018) The relationship between spindly leg syndrome incidence and water composition, overfeeding, and diet in newly metamorphosed harlequin frogs (Atelopus spp.). PLoS ONE 13(10): e0204314. https://doi.org/10.1371/journal.pone.0204314 

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.