The global status of Harlequin frogs

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Our planet is home to almost 9,000 amphibian species. For more than 100 years, these animals have dramatically suffered the consequences of deforestation, agriculture, wetland drainage, agrochemicals and other pollutants. In recent times, new threats have emerged making 40% of all amphibian species threatened with extinction under “Red List” released by the International Union for the Conservation of Nature (IUCN), which was recently updated. New threats include climate change and emerging infectious diseases. Among them, amphibian chytrid fungi causing skin infections play a key role. These fungi have been spread all over the world by humans and induce the disease chytridiomycosis in amphibians, leading to population declines and even extinctions.

Toad Mountain harlequin frogs from  the Darien.

Already 30 years ago, researchers, conservationists and other stakeholders have realized the crisis the amphibians are in. Various initiatives, at the global, regional and local scales have been founded to safeguard amphibian diversity including numerous management and action plans. Due to these activities, we massively augmented our knowledge about where declines happen, as well as the mechanisms behind these and how threats interact. This goes hand in hand with enormous engagement for protecting natural habitats and accompanying captive breeding in conservation facilities. Also, diseases and their agents are much better understood. There have been many stories of success and without all the investment, work and passion of dedicated actors many amphibian species would have become extinct by now!

However, it is difficult to appreciate where we stand in overcoming the amphibian crisis. Threats and the vulnerability to them are not equally distributed over all species. Certain amphibians are more susceptible and suffer more. They represent ‘worst-case scenarios’ of the amphibian crisis. For many of them, we lack sufficient information to access their current status. Not so for harlequin toads, genus Atelopus, from Central and South America. These are small, often colourful and day-active animals that inhabit lowland rainforests to high Andean moorlands (páramos) above tree line.

More than 130 Atelopus species are known and – being highly sensitive to threats – many of them have declined and are even feared extinct. Harlequin toads are the poster child of the amphibian crisis, and due to their iconic appearance, scientists have studied population status data since the early 1990s. In a recent study published in Communications Earth and Environment, Lötters and 99 colleagues, mostly conservationists and researchers from countries where harlequin toads naturally occur, compared population status data as of 2004 and of 2022 to examine species-specific trends over the last two decades.

Data from the authors confirm that massive conservation efforts from many scientists, conservationists and local communities have revealed that more than 30 Atelopus species that in part were feared to have vanished are still there! However, evidence suggests that at the same time all species remain threatened and their conservation status has not improved. Factors threatening the remaining harlequin toads remain unchanged and include habitat change and chytrid fungus spread. In addition, the authors demonstrated that in the future harlequin toads suffer from climate change.

Authors conclude that other worst-case amphibians continue to be imperilled demonstrating that the amphibian crisis is still an emergency. Thanks to the tremendous strength put into conservation, by collaborative networks like the recently launched Atelopus Survival Initiative under the umbrella of the Atelopus Task Force of the IUCN Amphibian Specialist Group, these amphibians have not yet vanished. It is now more than ever critical to continue and increase efforts to escape the emergency the amphibian crisis still is.

Lötters, S., A. Plewnia, A. Catenazzi, K. Neam, A.R. Acosta-Galvis, Y. Alarcon Vela, J.P. Allen, J.O. Alfaro Segundo, A. de Lourdes Almendáriz Cabezas, G. Alvarado Barboza, K.R. Alves-Silva, M. Anganoy-Criollo, E. Arbeláez Ortiz, J.D. Arpi L., A. Arteaga, O. Ballestas, D. Barrera Moscoso, J.D. Barros-Castañeda, A. Batista, M.H. Bernal, E. Betancourt, Y.O. da Cunha Bitar, P. Böning, L. Bravo-Valencia, J.F. Cáceres Andrade, D. Cadenas, J.C. Chaparro Auza, G.A. Chaves-Portilla, G. Chávez, L.A. Coloma, C.F. Cortez-Fernandez, E.A. Courtois, J. Culebras, I. De la Riva, V. Diaz, L.C. Elizondo Lara, R. Ernst, S.V. Flechas, T. Foch, A. Fouquet, C.Z. García Méndez, J. E. García-Pérez, D.A. Gómez-Hoyos, S.C. Gomides, J. Guerrel, B. Gratwicke, J.M. Guayasamin, E. Griffith, V. Herrera-Alva, R. Ibáñez, C.I. Idrovo, A. Jiménez Monge, R.F. Jorge, A. Jung, B. Klocke, M. Lampo, E. Lehr, C.H.R. Lewis, E.D. Lindquist, Y.R. López-Perilla, G. Mazepa, G.F. Medina-Rangel, A. Merino Viteri, K. Mulder, M. Pacheco-Suarez, A. Pereira-Muñoz, J.L. Pérez-González, M.A. Pinto Erazo, A.G. Pisso Florez, M. Ponce, V. Poole, A.B. Quezada Riera, A.J. Quiroz, M. Quiroz-Espinoza, A. Ramírez Guerra, J.P. Ramírez, S. Reichle, H. Reizine, M. Rivera-Correa, B. Roca-Rey Ross, A. Rocha-Usuga, M.T. Rodrigues, S. Rojas Montaño, D.C. Rößler, L.A. Rueda Solano, C. Señaris, A. Shepack, F.R. Siavichay Pesántez, A. Sorokin, A. Terán-Valdez, G. Torres-Ccasani, P.C. Tovar-Siso, L.M. Valencia, D.A. Velásquez-Trujillo, M. Veith, P.J. Venegas, J. Villalba-Fuentes, R. von May, J.F. Webster Bernal & E. La Marca (2023): Ongoing harlequin toad declines suggest the amphibian extinction crisis is still an emergency. — Communications Earth and Environment, 4, 412. https://www.nature.com/articles/s43247-023-01069-w

Check out this polka-dot color form of Vicente’s dart frog

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Around 2004, a poison dart frog resembling the polka dot poison dart frog Oophaga arborea was smuggled into the European pet trade. The striking animal had yellow dots characteristic of the species and caused a sensation. Part of the excitement is because Oophaga arborea is a critically endangered species is from a very small known distribution where it inhabits bromeliads in the tree canopies. It was thought to be common in the 1980’s but may have declined due to chytridiomycosis. According to the IUCN redlist it was last seen in 2012, but was possibly heard from the Fortuna forest reserve more recently. Could this animal indicate that the polka dot poison dart frog survived the amphibian chytrid epidemic?

Small brown poison dart frog covered with with pale yellow dots

Male Oophaga vicentei photographed by Ariel Rodríguez

In June 2022, a population of frogs with yellow spots resembling the polka dot poison frog was discovered in Veraguas, outside the known distribution of the polka dot frog. The researchers collected a few specimens and analyzed them genetically where they most closely matched Vicente’s poison frog Oophaga vicentei. These dart frogs are known to be highly polymorphic, coming in slate gray, metallic blue, yellow or brick red with mottling. The yellow polka dot version, however, has now been confirmed to be Vicente’s poison dart frog as opposed to strawberry poison dart frogs Oophaga pumilio, or Oophaga arborea. Vicente’s poison dart frogs are listed by the IUCN as an endangered species, they can be locally abundant in places they are found and are known from a small area in Panama.

The paper was published in the journal Salamandra: Monteiro JPC, Ibáñez, R,  Mantzana-Oikonomaki, V.,  Pröhl, H.,  Rodríguez, A. (2023)  Genetic diversity of Oophaga vicentei (Anura: Dendrobatidae) and taxonomic position of a remarkable color morph from Panama. Salamandra 59 (4): 347-351

Amphibians remain the most imperiled vertebrate class and they need our help

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Habitat destruction and disease are both well-documented causes of the decline of amphibians—among the most threatened animals on the planet—but a new paper analyzing two decades’ worth of data from around the world has found that climate change is emerging as one of the biggest threats to frogs, salamanders, and caecilians. The study was published today, Oct. 4, in the scientific journal Nature.

The study, “Ongoing declines for the world’s amphibians in the face of emerging threats,” is based on the second global amphibian assessment, coordinated by the Amphibian Red List Authority, which is a branch of the International Union for Conservation of Nature’s Species Survival Commission’s Amphibian Specialist Group, hosted and managed by Re:wild.

The assessment evaluated the extinction risk of more than 8,000 amphibian species from all over the world, including 2,286 species evaluated for the first time. More than 1,000 experts across the globe contributed their data and expertise, which found that two out of every five amphibians are threatened with extinction. These data will be published on the IUCN Red List of Threatened Species™.

Between 2004 and 2022, a few critical threats have pushed more than 300 amphibians closer to extinction, according to the study. Climate change was the primary threat for 39% of these species. This number is expected to rise as better data and projections on species’ responses to climate change become available. Climate change is especially concerning for amphibians in large part because they are particularly sensitive to changes in their environment.

Small red poison dartfrog called Andinobates geminisae carrying a tadpole on his back

Geminis’ dart frog is a critically endangered Panamanian amphibian that was only recently described. It is known from an area just 40km 2, males care for the offspring and transport tadpoles on their backs.

“As humans drive changes in the climate and to habitats, amphibians are becoming climate captives, unable to move very far to escape the climate change-induced increase in frequency and intensity of extreme heat, wildfires, drought and hurricanes,” said Jennifer Luedtke Swandby, Re:wild manager of species partnerships, Red List Authority coordinator of the IUCN SSC Amphibian Specialist Group, and one of the lead authors of the study. “Our study shows that we cannot continue to underestimate this threat. Protecting and restoring forests is critical not only to safeguarding biodiversity, but also to tackling climate change.”

Habitat destruction and degradation as the result of agriculture (including crops, livestock like cattle and livestock grazing, and silviculture), infrastructure development and other industries is still the most common threat, according to the paper. Habitat destruction and degradation affect 93% of all threatened amphibian species. Expanded habitat and corridor protection in the places most important for biodiversity is going to continue to be critical.

Disease caused by the chytrid fungus–which has decimated amphibian species in Latin America, Australia and the United States–and overexploitation also continue to cause amphibian declines. Habitat destruction and degradation, disease, and overexploitation are all threats that are exacerbated by the effects of climate change.

The study also found that three out of every five salamander species are threatened with extinction primarily as the result of habitat destruction and climate change, making salamanders the world’s most threatened group of amphibians. North America is home to the most biodiverse community of salamanders in the world, including a group of lungless salamanders abundant in the Appalachian Mountains of the eastern United States. Because of this, conservationists are concerned about a deadly salamander fungus that has been found in Asia and Europe, called Batrachochytrium salamandrivorans (Bsal), entering the Americas.

“Bsal has not yet been detected in the United States, but because humans and other animals can introduce the fungus to new places, it may only be a matter of time before we see the second global amphibian disease pandemic,” said Dede Olson, a research ecologist with the USDA Forest Service, member of the IUCN SSC Amphibian Specialist Group, and co-author on the paper. “It is critical that we continue to implement proactive conservation actions to prevent the spread of Bsal into the United States, including effective biosecurity practices for wild and captive amphibians, and rapid detection and response measures. The North American Bsal Task Force includes a multi-pronged strategic plan that includes: a continental surveillance and monitoring network; research studies identifying high-risk geographies and species; and collaborative partnerships across public, private, and governmental sectors.”

The Nature paper provides an update to the 2004 landmark paper that was based on the first global amphibian assessment for the IUCN Red List, which revealed the unfolding amphibian crisis for the first time and established a baseline for monitoring trends and measuring conservation impact. According to this new study, nearly 41% of all amphibian species that have been assessed are currently globally threatened, considered critically endangered, endangered or vulnerable. This is compared to 26.5% of mammals, 21.4% of reptiles and 12.9% of birds.

Four amphibian species were documented as having gone extinct since 2004—the Chiriquí harlequin toad (Atelopus chiriquiensis) from Costa Rica, the sharp snouted day frog (Taudactylus acutirostris) from Australia, Craugastor myllomyllon and the Jalpa false brook salamander (Pseudoeurycea exspectata), both from Guatemala. Twenty-seven additional critically endangered species are now considered possibly extinct, bringing the total to more than 160 critically endangered amphibians that are considered possibly extinct. The assessment also found that 120 species improved their Red List status since 1980. Of the 63 species that improved as the direct result of conservation action, most improved due to habitat protection and management.

“The history of amphibian conservation itself proves how vital this information is,” said Adam Sweidan, chair and co-founder of Synchronicity Earth. “If the IUCN Red List had been updated on a similar scale in the 1970s that it is today, we could have traced the sweeping amphibian disease pandemic 20 years before it devastated amphibian populations. It isn’t too late–we have this wealth of information, we have the Amphibian Conservation Action Plan, but plans and information are not enough. We need to act. We need to act fast.”

Conservationists will use the information from this study to help inform a global conservation action plan, to prioritize conservation actions at the global level, to seek additional resources, and to influence policy that can help reverse the negative trend for amphibians.

Citation: J.A. Luedtke, J. Chanson, K. Neam, L. Hobin et. al. 2023. Ongoing declines for the world’s amphibians in the face of emerging threats. Nature. https://doi.org/10.1038/s41586-023-06578-4 

Happy 13th Golden Frog Day!

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Every year on August 14th, Panamanians officially celebrate golden frog day as a symbol of Panama’s incredible biodiversity and cultural diversity. This year we are thrilled to share the original song “La Rana Dorada” by National Geographic explorer Janni Benavides of Jacana Jacana. The song is one of four original scores developed as part of a National Geographic Meridian Grant supporting the Atelopus Survival Initiative.

On spotify https://open.spotify.com/album/3C3J2FJXRyxYGKLffGXyEe

On you tube https://youtu.be/LwxzgzKa40A 

Following reintroduced frogs

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The Panama Amphibian Rescue and Conservation Project completed the first reintroduction trial of the Limosa Harlequin frog (Atelopus limosus) in 2017, and our findings were published in the journal Frontiers in Amphibian and Reptile Science. Reintroducing a species comes with a lot of unknowns and questions, just a few are: Where will the frogs go? What is their life like outside of a terrarium? Will they become infected with amphibian chytrid fungus? The purpose of this first reintroduction trial was to begin to unravel some of these questions so the researchers could adapt their strategies and improve the odds of the frogs in the wild.

We were able to get a detailed life of the frogs post-reintroduction by radiotracking the frogs and checking in on them daily. We found that when frogs were provided a 30-day acclimation period in a predator-free rainforest mesocosm, their probability of survival significantly increased and they did not disperse as far as the hard-released animals. We know from other studies that more movement can increase the likelihood of predators finding animals, and that likely happened in this study too. Frogs that were released without radio transmitters were 44x less likely to be reencountered during stream surveys (finding a frog in the rainforest isn’t easy!). We were able to follow the lives of these frogs in the wild for up to 56 days after release and developed a method that can use both radio-tracked animals and non-radiotracked animal encounters to estimate survivorship by assigning different detection probabilities in the model.

We observed a couple predation events of reintroduced frogs and some became infected with amphibian chytrid fungus. However, we learned a lot and has no shortage of questions to continue researching to get this species (and others in Panama) back into the wild.

Read the open access paper here:
Klocke, B., Estrada, A., Mataya, M., Medina, D., Baitchman, E., Belden, L., Guerrel, J., Evans, M., Baughman, J. and Connette, G., Illueca, E., Ibáñez, R., Gratwicke, B. (2023) Movement and survival of captive-bred Limosa Harlequin frog (Atelopus limosus) released into the wild. Frontiers in Amphibian and Reptile Science, 1, p.1205938. https://doi.org/10.3389/famrs.2023.1205938 

by Blake Klocke

The Golden Frog Song

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Enjoy this performance of “La Rana Dorada” one of four original songs by National Geographic explorer Jani Benavides of Jacana Jacana as part of the Atelopus Survival Initiative and National Geographic Meridian Grant meeting hosted by the Fundacion Atelopus and Re:wild in Sierra Santa Marta.

Insectarium

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Construction of our new insect facility was completed and fire suppression systems installed. This new 1,600 square feet insectarium has two climate-controlled rooms that can be maintained at different temperatures, allowing a diversity of food items with varying sizes and nutritional properties to meet the needs of our diverse amphibian collection. A huge thanks to the STRI Office of Facilities and Engineering who oversaw this project and to the many individual donors, the Cheyenne Mountain Zoo, Zoo New England, the Houston Zoo, the Holtzman Foundation, the Shared Earth Foundation for enabling us to complete it.

Under the leadership of Nancy Fairchild and Jennifer Warren, our insect production capacity is now one of the incredible success stories of our project. There are no local sources of captive-reared insects, so we are 100% reliant on our own production and have redundant capacity to accommodate any unexpected changes in the populations of the various springtails, fruitflies, crickets, pantry moths, soldier flies, cockroaches and earthworms that we produce. This team has also conducted original research to develop gutloading propocols for springtails and demonstrated improved outcomes of juvenile frogs reared on this nutritionally supplemented prey, compared to their normal yeast-based diets.