Skin Secretions of Frogs

Any of several small, often brightly colored earthly frogs that inhabit the rain forests of Central and South America and secrete from their skin some of the most poisonous biological toxins known, such as batrachotoxin.

It is on the forest floor that the native South Americans find the jewel-like poison dart frog. The Choco' tribe in Colombia, South America uses the skin secretions to poison their dart tips. One technique used to treat darts requires that a sharp stick to be forced into the frog's mouth and down its throat. While on the stick, the frog is held over a fire. This causes the animal much stress and it begins to release the toxic alkaloids and produces a white bubble. Darts that are dipped or rolled in this secretion and allowed to dry remain strong for about a year. After the white bubbles stops, a yellow substance is secreted. This is scraped off and once dried remains strong for up to 12 months. One frog will produce enough poison to treat as many as 50 darts. This poison will kill small animals such as monkeys and birds. When using Phyllobates terribilis, the native people do not kill the frogs, but scrape the darts on the animals' back to stimulate poison secretion and then release them. In areas where there are no poison dart frogs or if larger game is wanted, the Indians use a plant poison called curare to treat arrows and blowgun darts. Often, curare, which may be mixed with other toxins, is confused with the skin poison found in frogs, used to treat darts. This is part of the reason why the amphibians are sometimes called "poison arrow frogs" as well as "poison dart frogs."

The use of poison dart frogs in this way is actually limited to certain regions of Colombia, South America, where the more toxic varieties of frogs are found. Only three species are actually toxic enough to be used to produce effective blowgun darts. This includes the highly toxic Phyllobates terribilis and its close relatives Phyllobates bicolor and Phyllobates aurotaenia. All occur west of the Andes Mountains in Colombia. However, more modern methods of hunting, such as guns, are rapidly replacing poison darts. Also it is thought that rain forest destruction has lowered the numbers of both Dendrobates and Phyllobates.