Cane Toads

Giant Neotropical Toad
Cane Toad
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Amphibia Order: Anura Family: Bufonidae Genus: Bufo Species: marinus
Binomial name
Bufo marinus Linnaeus, 1758

The Giant Neotropical Toad (Bufo marinus) is native to the Americas from southern Texas to northern Argentina. It has been introduced to many locations in the belief it will control agricultural pests, particularly of sugarcane. Introduced populations now occur in Australia, Florida, Papua New Guinea, the Philippines, the Ogasawara Islands and Ryukyu Islands of Japan, most Caribbean islands and many Pacific islands including Hawai'i and Fiji.

Some individuals reach exceptional sizes for an anuran. A preserved specimen in the museum of Queensland is 24cm long and weighed 1.36kg. They can live as long as twenty years in captivity, but usually they live for 15 years in the wild.

Adults possess enlarged paratoid glands behind the eyes and other glands across the back. When the animal is harassed these glands secrete a milky-white fluid known as bufotoxin. Bufotoxin contains components which are dangerous to many animals. There are reported deaths of humans after consumption of toads. Ill-effects from contact with toads have also been reported and they should be handled with caution. However they are sometimes kept as pets.

Adults are omnivores which is unusual for an anuran. Their prey includes small vertebrates, a wide range of invertebrates, carrion and plant material. They even been known to attempt to eat ping pong balls. They are active primarily at night, ranging far away from water.

Females lay from 4,000 to 36,000 eggs per clutch, and breed at least twice per year. Both eggs and tadpoles are toxic to many animals. This toxic protection is lost for a period after metamorphosis until the paratoid glands develop.

Introduction to Hawaii

This toad was introduced into Hawai'i in 1932 from Puerto Rico to control injurious insects in the sugarcane fields.

Introduction into Australia

101 toads were brought to Australia from Hawai‘i in June 1935 in an attempt to control pests to sugarcane crops. They bred immediately in captivity and by August 1935 over 3000 young toads had been released in areas around Cairns, Gordonvale and Innisfail in northern Queensland. Releases were temporarily limited due to environmental concerns, but resumed in other areas after September 1936. Since their release, toads have steadily expanded their range through Queensland, reaching the border with New South Wales in 1978 and the Northern Territory in 1984.

There are grave concerns that toads might affect Australia's native fauna by predation, competition, conveying diseases and by poisoning animals that attempt to prey on toads. The long-term impact of toads on the Australian environment is difficult to determine. Precipitous declines in populations of the Northern Quoll have been observed after toads have invaded an area. There are also a number of reports of goanna and snake populations collapsing after the arrival of toads. [1] (http://news.bbc.co.uk/2/hi/science/nature/4073359.stm)

A number of native species have been reported as successfully preying on toads. Some birds, such as the Torresian Crow and the Black Kite, have learned to attack a toad's belly, avoiding the venom-producing glands on the behind the head. Recent reports by researchers in the Northern Territory indicate that a native frog Litoria dahlii is apparently able to eat the tadpoles and live young of the toad without being affected by the poison that often kills other predators. This is believed to account for slower than expected infestations of toads in certain areas of the Northern Territory.

The saga of the Cane toad in Australia was popularized by the film Cane Toads: An Unnatural History (1987) which tells the tale with a humorous edge and is often shown in Environmental Science courses.

Other names

The Giant Neotropical Toad is also known by the following names:

• Aga Toad (German, origin unknown)
• Cane Toad
• Crapaud (Trinidad and Tobago)
• Dominican Toad
• Giant Marine Toad
• Giant Toad
• Marine Toad
• Sapo gigante (Spanish)
• South American Cane Toad
• Spring Chicken (in Belize)
• Sapo Cururu (in Brazil)