The Human
Threat
The
human population of Panama is growing, and
many environmental problems have paralleled this growth.
The Panamanian Golden Frog has had to struggle for
survival in ways that are similar to that of other species. New
subdivisions are being planned and built on existing Golden Frog habitat.
The PGF research team has encountered frog populations that are currently being
deforested for the lumber needs of these communities.
Growth in rock mining for home construction and decor
also has played a part in habitat alteration of the species.
Agrochemicals used by watercress farmers to ward off insects and fertilize crops have toxified numerous streams within the range of the Golden Frog. Sevin (carbaryl) is a commonly used pesticide in Central America that has demonstrated lethal concentration as low as 4 ppm in some amphibians. It would be difficult to speculate how many populations have been impacted by toxification.
Added to the threat of agricultural chemicals has been the sustained encroachment and loss of habitat due to poor human land use. Deforestation, particularly for cattle ranching, appears to have been an important factor in the reduction of this endangered species.
Another historic threat for the Golden Frog has been over-collection. Due to the beauty and legendary mystique of the Golden Frog, natives used to collect the frog as talismans. Thousands of golden frogs were sold by local merchants at the famous Sunday market in El Valle de Antón. This town that had gained its identity in part by the frog has had its populations extirpated (locally extinct) for 40 - 50 years.
Due to population growth, farming, and illegal collection,
the Golden Frog of Panama has a narrow chance for survival outside of the
national park system.
A
Natural Threat?
One would think with all of the human stresses exerted
against the frog, it would have become extinct years ago.
Amazingly, this species has withstood the odds in small geographic
patches of suitable habitat.
Unfortunately, there now stands a new threat that could give the final blow to the species. A chytridiomycete fungus, called Batrachochytrium dendrobatidis (notoriously called, "the chytrid" - pronounced 'kitchrid'), recently has been found in three localities in western Panama. This fungal pathogen attacks keratin in the dermal tissue of amphibians. It is believed by many researchers that this pathogenic fungus disables the frog from being able to respire and osmoregulate, eventually killing the frog. The disease is known as chytridiomycosis.
Although there is a cure for chytridiomycosis in captive settings, there is no treatment against the chytrid in the wild. To make matters worse the epizootic (broad disease outbreak in animals) is spreading. The fungus appears to be moving as a wave-like front from west to east through the isthmus. It is estimated that within four years all middle to high elevation, creek-dwelling amphibians (including the Golden Frog) will be desimated.
The threat of the chytrid adds to the existing threats of pollution, poaching, and deforestation, giving the Golden Frog a bleak future in the wild. Keeping the spread of this disease from populations within the national park system is impossible at this time.
Amphibians
in Trouble Worldwide
The disappearances of amphibians in Panama are not problems localized to the neotropics. Around the world amphibians of all kinds are disappearing from the same factors that are affecting Panama. Factors such as the chytrid, UV exposure, and scads of anthropogenic causes have been identified as problems to amphibians all around the world.
Amphibians are like a litmus to the animal kingdom. If there are any changes to the environment due to pollution or habitation lost, amphibians appear to be among the first to be effected. This is likely the reason why there are such large scale extirpations and extinctions of amphibians around the world. Amphibians are directly and indirectly effected by human attempts to manipulate and control their environment.
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