Classification and Range
The Panamanian golden frog belongs in the order Anura (frogs and toads), the family Bufonidae and the genus Atelopus. Before the 1975 discovery of zetekitoxin, a toxin unique to the Panamanian golden frog, it was considered a subspecies of Atelopus varius. Now it stands alone as a distinct species. There are 82 species of Atelopus that range from Costa Rica to northern Andes, throughout Venezuela, the Guianas and the Amazon basin. Atelopus zeteki is endemic to cloud forests of central western Panama; however, it may now be extinct in the wild with the most recent sightings in 2006.
Panamanian golden frogs inhabit tropical lowland or mid-montane rainforest at elevations from 1,300 feet (396 m) to almost 4,000 feet (1,219 m). Whether in wet forest or dry forest, these frogs require streams or waterfalls.
Panamanian golden frogs have been described as “frog-like toads” or “toad-like frogs.” The question is: are they toads or frogs? To start with, all toads are frogs. However, not all frogs are toads; the word toad is often used for other frogs and the terms can be misleading. The family Bufonidae contains “true toads” that have squat bodies, short limbs, dry “warty” skin and no teeth.
Also, most “true toads” possess a pair of specialized parotoid glands behind the eyes, which secrete a number of toxins that act as protection from predators. In contrast, frogs have a longer, slender body; longer limbs for jumping and webbed feet for swimming; smooth, wet-looking skin; teeth in their upper jaws; a prominent external eardrum (or tympanum) and a longer, pointed snout. Many species in the genus Atelopus, including the Panamanian golden frog, have smooth skin, slender bodies, long limbs with some toe webbing, and pointed snouts. However, they also have no tympanum or teeth, but do possess poison glands.
While Atelopus zeteki belongs to the Bufonidae family of “true toads,” its name claims “frog.” Adult male and female Panamanian golden frogs have similar coloration; juveniles of both sexes are also similar to each other and their parents. Panamanian golden frogs have a wide range of color, from deep, egg-yolk gold to light yellow or yellowish green. Adults may acquire black dorsal markings or spots otherwise absent in the solid yellow-colored juveniles and sub-adults. All ages and both sexes are a bright yellow on their undersides.
Size and Weight
While this species is small in size, adult females are larger than adult males. Females measure 1.77 – 2.48 inches (4.5 – 6.3 cm) and males 1.38 – 1.89 inches (3.5 – 4.8 cm). Females weigh .14 – .53 ounces (4 – 15 g) and males .11 - .42 ounces (3 – 12 g). Panamanian golden frogs from dry forest streams are about two-thirds the size of those from wet forest streams.
Unknown in the wild. Captive frogs have lived up to 9 years.
In the wild: a wide variety of small invertebrates (ants, beetles, flies, wasps, silverfish, springtails, spiders and caterpillars). At the zoo: a variety of invertebrates that include: crickets, fruit flies, flower beetles, springtails and occasional waxworms.
During the late dry or early rainy season (February – March), females may move into forests where they live on the forest floor. In the late rainy or early dry season (November – January), as water levels in streams are at their lowest, the females return to streams for breeding. Meanwhile, males remain year-round by streams staking out territory and awaiting the arrival of females near the water’s edge.
Besides sounds such as “chirping,” both sexes use semaphore (visual signals) as a means of communication. It is possible that the noise of rapid currents from nearby streams necessitate this sign language. For males, their hand-waving system evidently wards off rivals and attracts females. Competing males may wrestle each other, with the victor ending on top and the vanquished keeping its head down. When encountering a female, no courtship occurs; the male climbs on top of the female and achieves amplexus (pseudocopulation). In this sexual embrace, the male attaches himself to the female’s body with his forelimbs in a strong grasp. They may remain in amplexus from a few days to over a month. Another male may even join the first male atop the female’s back, but the secondary male does not achieve amplexus and eventually drops off.
The female attaches a looped string of eggs (average clutch size is 370) to a boulder in a quickly flowing stream. Hatchlings emerge from seven to 11 days later. The larvae have a suction disc for attachment to submerged objects; this prevents them from being swept away by currents. As they grow, the developing tadpoles match the coloration of the sandy stream bottom. Depending on water conditions, it takes anywhere from four to eight months for the larvae to metamorphose into miniature frogs.
Later on, the newly metamorphosed frogs and young juveniles turn green with dark brown and black markings that match their mossy habitat. Young frogs initially lack the skin toxins of the adults, so this coloration acts as camouflage for them. Panamanian golden frogs obtain their skin poisons from their natural diet of invertebrates, especially ants that contain formic acid.
As older juveniles and sub-adults, they acquire the characteristic golden coloration and eventually the adult black markings. As adults, these frogs are diurnal moving about on mid-stream boulders and stream edges; during the day time, they openly move throughout the forest floor.
A Devastating Dinner - Don't Eat That Frog!
All Atelopus species of frogs have multiple neurotoxins and cardiotoxins in their skin that are capable of killing 100 mice, assuming each mouse weighs .71 ounces (20 g). However, out of all Atelopus species, adult Panamanian golden frogs are the most toxic.
In addition to multiple neurotoxins and cardiotoxins, Atelopus zeteki possesses two forms of zetekitoxin, a potent nerve poison. Researchers have identified that one individual Panamanian golden frog contains enough toxins to kill 1,200 mice. These frogs appear to be aposematic, in which the animal’s coloration signals a means of defense. Therefore, it is not surprising that these brilliantly hued frogs can be both terrestrial and diurnal, as they distinctively amble through their environment with a casual response to potential predators
Prominent Presence in Panama
This frog is a national symbol of Panama. In pre-Colombian times, Panamanians revered this frog, which represented prosperity and fertility. Local chieftains performed sacred rites upon the lands where these frogs lived. These early people created gold or clay huacas/huacos (talismans) in the form of frogs and buried them.
The originals are highly prized and highly priced. Today, stores and shops commonly sell modern replicas along with many other objects with this frog’s image. Legends about this frog tell that upon dying, the rana dorada (golden frog) actually became a golden huaca. Over time, seeing or possessing a live one meant good fortune. Panamanian lottery tickets currently feature the frog as a continuation of this belief.
Location at the Zoo
Woodland Park Zoo's Panamanian golden frogs are on display in the Day Exhibit. The zoo also keeps a number of other amphibian species on or off exhibit, the latter for breeding purposes. Other species of amphibians can be seen in the Day Exhibit and in the award-winning Tropical Rain Forest. They include the axolotls, poison dart frogs, smooth-sided toads and the African gray tree frogs.
Panamanian golden frogs are an endangered species. Most sources declare their extinction in the wild as of 2006. As recently as 2005, this species was reasonably common at a number of localities and easily recorded. In recent decades, its distribution has dropped rapidly and in many parts of its range, it is either very rare or extinct. Recently, chytridiomycosis (see more below) has drastically reduced or even completely collapsed formerly stable populations. As chytridiomycosis spreads from west to east through Panama, populations in the eastern part of its range are now at severe risk of disappearing.
The biggest threat to the survival of amphibians is loss of habitat from human–caused activities. These activities include drainage of wetlands for agriculture, housing, logging and construction of roads. Frogs and toads are particularly vulnerable, since humans often develop the land next to lakes, rivers and streams where these animals come to lay their eggs. Due to their inability to tolerate habitat alteration, most amphibians cannot maintain sustainable levels with the presence of these threats. Pollution, climate change and invasive species introduced by humans also take their toll on local amphibian populations.
Over the past 50 years, scientists have recorded major declines in frog populations around the world. A few species have vanished completely. Scientists continue to search for answers, as a newly-discovered fungal disease (Batrachochytrium dendrobatidis – aka chytridiomycosis) presents the most potent natural threat. In 1999, researchers identified this fungus as responsible for massive extinctions of wild amphibians worldwide. Researchers believe that chytridiomycosis kills by suffocation and disruption of thermoregulation. Chytrid fungus spreads rapidly and apparently does not easily disappear from the environment, even after all the former amphibians die. Cures for it exist; however, it is not practical for those in the wild due to likely re-infection.
Project Golden Frog (PGF) (in Spanish, Proyecto Rana Dorada) seeks to ensure the survival of the charismatic and culturally significant Panamanian golden frog. PGF is an international conservation consortium of Panamanian and U.S. institutions. The overall goals of PGF include: public awareness of global threats to amphibians; greater understanding of endangered species and the need for land preservation; and coordinated efforts between governmental agencies and educational or zoological organizations. PGF coordinates conservation projects in El Valle de Anton, Panama and several U.S. institutions. Zoos such as the Denver Zoo and National Aquarium in Baltimore also participate by providing successful captive breeding programs. When the threat of the chytrid fungus is gone or reduced, PGF hopes to re-introduce captive bred tadpoles in Panamanian national parks. Learn more at http://www.ranadorada.org/.
Panamanian golden frogs rarely show up in the international pet trade, as they are essentially extinct in the wild. The increasing demand of the pet trade lowers numbers of many amphibian populations to the point where they may become extinct in the wild. Every year, many more wild-caught animals die than ever reach pet stores. Those that survive are often stressed, malnourished and untamable. In recent years, humans have heavily imported many species of frogs and toads as increasing numbers of pet store owners want to sell them. One way to decrease demand for importation of reptiles is for potential owners to demand captive-born individuals.
Amphibians as Pets
Since amphibians and reptiles require very specialized diets and environments, Woodland Park Zoo (WPZ) does not recommend them as pets for most people. WPZ also receives hundreds of requests each year to take former pet toads, frogs and other amphibians but we cannot accept these due to space, health and unknown backgrounds.
If you need to find a reptile or amphibian a new home, we suggest you contact a local herpetological group in your area. In the Puget Sound region, it is the Pacific Northwest Herpetological Society. Anyone interested in owning a reptile or amphibian should learn about its needs and be sure it was captive-bred. Read more about keeping a reptile by visiting: http://www.kingsnake.com/ballpythonguide/pets.htm.
How You Can Help!
The effort to save endangered species like the tomato frog requires cooperation and support at the international, national, regional and individual levels. You can help in this cause. Join and become active in Woodland Park Zoo and other conservation organizations of your choice. Don't buy products made from wild animal parts.
Contact your elected representatives and express your views about conservation of endangered species and wild habitats. Contact Woodland Park Zoo at email@example.com to find out other ways you can support conservation programs at the zoo. Discover more about Panamanian golden frogs by contacting the Society for the Study of Amphibians and Reptiles at http://www.ssarherps.org, or the American Federation of Herpetoculture: AFH, PO Box 300067, Escondido, CA 92030-0067. Find other groups and information online at http://www.parcplace.org, the website of Partners in Amphibian and Reptile Conservation, or by searching the keyword "herpetology." Learn other ways you can help conserve wildlife and the habitats they require for survival by visiting our How You Can Help page.
Sources and Suggested Reading
AmphibiaWeb: Information on amphibian biology and conservation. 2008. Accessed July 9, 2008 at www.amphibiaweb.org/lists/Bufonidae.shtml
BBC News: Science/Nature: ’Last wave’ for the wild golden frog. Video. 2008. Accessed July 9, 2008 at news.bbc.co.uk/2/hi/science/nature/7219803.stm
Denver Zoo: Conservation in the Field: Project Golden Frog. 2006. Accessed July 9, 2008 at www.denverzoo.org/conservation/project10.asp IUCN, Conservation International and NatureServe.
Atelopus zeteki - Golden Arrow Poison Frog, Golden Frog, Panamanian Golden Frog, Zetek's Golden Frog. 2006. Global Amphibian Assessment (GAA). Accessed July 15, 2008 at www.globalamphibians.org/servlet/ GAA?searchName=Atelopus+zeteki
Project Golden Frog. 2008 Accessed July 9, 2008 at www.ranadorada.org/
Rocky Mountain News: Panamanian golden frog facing doom. 2006. Accessed July 9, 2008 at m.rockymountainnews.com/news/2006/ Nov/27/panamanian-golden-frog-facing-doom/
Savage, Jay M. Amphibians of Costa Rica. 2002. University of Chicago Press, Chicago. Smithsonian National Zoological Park: Animals, etc.: Reptiles & Amphibians: News & Events. 2006. Accessed July 9, 2008
The Washington Post: Panama Hotel Is Imperiled Frogs’ Lifeboat. 2006. Accessed July 9, 2008 at pqasb.pqarchiver.com/washingtonpost /search.html The Washington Post: Panama Hotel Houses Rescued Frogs. Video. 2006. Accessed July 9, 2008 at www.washingtonpost.com/cp-cyn/content/video/ 2006/10/25/VI200601418.html.
Taxonomic classification varies between references.
Classification information used in this fact sheet was taken from: AmphibiaWeb: Information on amphibian biology and conservation. 2008. Berkeley, California: Accessed July 3, 2008 at www.amphibiaweb.org/lists/Bufonidae.shtml