The Mysterious Golden Toad

Location: The Golden toad’s habitat is 4 kilometres of cloud forest on the Cordillera de Tilarán in Northern Costa Rica. This mountain has an elevation of 2000-2100 m. The convergence of tectonic plates produced the mountain and its unique geographic condition

Year of extinction: 1992

About: Golden Toad (Bufo periglenes), other common names are Monteverde Golden Toad, or the Monte Verde Toad

Appearance: The Golden toad was discovered in 1967 and is an extreme example of sexual dimorphism, which means there is a marked visible difference between males and females. The male is a brilliant orange or golden colour, and the female is black with red regions outlined in yellow.

These differences do not appear until adulthood.

The Monteverde toad is the only toad that never exhibits any grey or brown. The male measures 39-48mm and the larger female 42-56mm.

Reproduction:

• Little is known about the Golden toad because it is rarely been seen outside of its breeding season. During April-June’s rainy season, the toads appear in enormous numbers in rainforest puddles.
• The males outnumber females 8:1 and have a high sex drive which urges them to mate with any moving object. The result of this is they will molest other mating pairs and form “toad balls” made up of 4-10 clasping males.
• A successful mating produces 200-400 eggs.
• It takes 5 weeks for the surviving tadpoles to grow into mature Golden Toads.
  

Food supply: The Golden Toad eats smaller invertebrates, insects, etc.

Lifestyle: Although not a lot was learned about the Golden Toad, similar species that live in the area habitually stay in underground tunnels. It is thought that this is also the case for the Golden toad, which may explain why few are seen outside of the breeding season.

Reason they are extinct:

1. It is thought that Climate Change is the main reason which led to the extinction
Climate changes are thought to explain the Golden Toads disappearance. Before the erratic weather of 1987, it is believed that a possible 30,000 Monteverde toads existed. Several were gathered in 1987, only 10 were found in 1988. The last Golden toad that was seen was in 1989. A concerted 5 year search effort was made before the species was declared extinct in 1992. Erratic weather patterns and rising temperatures have affected amphibians and their habitats across the globe.

2. Sensitive breeding conditions
Three months is a narrow window for breeding to take place in. This and the select geographic area of the Monteverde toad have left it vulnerable and inadaptable to change. If the rainy season is heavy the tadpoles are washed out of their pools. If the rainy season is light, the tadpoles desiccate along with the drying pools.

3. UV penetration
Recent studies show that increased UV penetration has a significant effect on amphibian reproduction. It lowers resistance to the common fungus saprolegnia.

4. Pollution
Pollution has weakened the immune systems of all amphibians. Research in 2000 found that a similar species was severely afflicted with chytridiomycosis, a skin disease from a normally harmless fungus. The disease causes amphibians to suffocate as they attempt to breathe through their skin.

5. Pesticides
The pesticide atrazine is commonly used in Costa Rica. Airborne contact is known to have serious effects upon the sexual development of toads and frogs.

6. Declining Habitat
Declining rain forest areas due to climate change and man have forced species into smaller habitats. This increases contact and the spread of disease.

Amphibians are often exploited by science for their role as a model organism. They are used for ecological, embryological, physiological and genetic research.

Amphibians and their importance

Amphibian species have been dying off at alarming rates. The 2005 Global Amphibian Assessment found that nearly 1/3 of amphibian species are threatened and 129 species became extinct since 1980.

Amphibians are a barometer for pollution because they take oxygen and water in through their skin.

Species diversity encourages evolutionary adaptation. Lowering gene pools means less hardy and adaptable species.

Amphibians are a major link in the food chain; insect consumers and a food source themselves to many animals.

Amphibians are the source of many known and yet unknown elements that may contribute to huge advances in medicine and cures for disease. The skin extract from one South American frog blocks pain 200 times better than morphine. -supergreenme