Frogger

Peter Herbolzheimer Rhythm Combination & Brass: Frog Dance
From: Wide Open (MPS, 1973)

DARWIN, Australia (March 28) - A "monster" cane toad the size of a small dog has been captured by an environmental group dedicated to wiping out the toxic amphibian, which has killed countless animals since being introduced to Australia in the 1930s.

The volunteer-run organization, Frogwatch, picked up the 15-inch-long cane toad during a raid on a pond outside the northern city of Darwin late Monday.

With a body the size of a football and weighing nearly 2 pounds, the "monster toad" is among the largest specimens ever captured in Australia, according to Frogwatch coordinator Graeme Sawyer.

"It's huge, to put it mildly," he said. "The biggest toads are usually females but this one was a rampant male ... I would hate to meet his big sister."

Cane toads were imported from South America during the 1930s in a failed attempt to control beetles on Australia's northern sugar cane plantations. The poisonous toads have proven fatal to Australia's delicate ecosystems, killing millions of native animals from snakes to the small crocodiles that eat them.

As part of its so-called "Toad Buster" project, Frogwatch conducts regular raids on local water holes, blinding the toads with bright lights then scooping them up by the dozen.

"We kill them with carbon dioxide gas, stockpile them in a big freezer and then put them through a liquid fertilizer process" that renders the toads nontoxic, Sawyer said.

"It turns out to be sensational fertilizer," he added.

Up until 1935, Australia did not have any toad species of it's own. We had tree frogs and burrowing ground frogs - even microhylid frogs which do not have a tadpole - but none of the world's hundreds of toad species evolved here. However, not wanting to be left out, Australia acquired some - 102 toads, in fact.

These toads were supposedly being used successfully in the Carribbean islands and in Hawaii to combat the cane beetle, a pest of sugar cane crops. After rave reviews from overseas, Hawaii shipped a box of toads to Gordonvale, just south of Cairns. These were held in captivity for awhile, their numbers were increased by breeding, and then they were released into the sugar cane fields of the tropic north. It was later discovered that the toads (scientific name Bufo marinus) can't jump very high so they did not eat the cane beetles which stayed up on the upper stalks of the cane plants. At the time of year when the beetle's larvae were emerging from the ground, no toads were about. So the cane toad, as it came to be known, had no impact on the cane beetles at all and farmers had to go back to the use of chemicals to kill the beetle.

Bufo marinus breed like flies, as the saying goes. Each pair of cane toads can lay 33,000 eggs per spawning (some published references estimate they produce as much as 60,000 eggs!).

Their 'toadpoles' develop faster than many Australian frogs so they can outcompete our frogs for food.

Toads and toadpoles seem to be resistant to some herbicides and eutrophic water which would normally kill frogs and tadpoles.

All stages of a toad's life are poisonous so they have no natural predators to keep their numbers in check (although studies suggests that toad juveniles are not toxic until they reach about 3cm in size but this presents a question: why would an animal lose its toxicity at the juvenile stage when it has it during larvae and adult stages?)

Toads not only eat the food normally available to Australian frogs, there is growing anecdotal evidence that they eat frogs as well, especially metamorphs.

Fish who eat toadpoles die. Animals who eat toad adults die. The museums have plenty of snakes preserved in jars which were killed by toad toxin so fast, the toad is still in their mouths unswallowed. Even small amounts of water, such as a pet's water dish, can be fouled by toadpoles and adults. When the pet comes along to drink from it's dish, it becomes sick. Local vets report that a couple dogs a month are brought in ill just from "mouthing" toads.

Some Queensland bird and rodent species have somehow learned how to eat cane toads without exposing themselves to the toxin. They kill the toad and turn it over onto its back. They pull away the soft belly skin and partake of the internal organs, leaving the skin and the deadly paratoid glands behind. This behaviour has only taken a mere 60 years to learn - very fast on the evolutionary scales. Those native rats which do feed on animal material (such as the White-tailed and the False Water) have learned to only eat the legs of the toad and not the body.

Captive cane toads will allegedly eat everything from dog food to mice and they keep growing until they reach 25cm in length and over 4 kilos. In recent years, it has been noticed that toads in the Cairns area are much smaller than they used to be (the "big mama" at right was found in Babinda - 30 minutes drive south of Cairns). A theory is that when toads first colonise a new territory, there is an abundant food supply. The toads gorge themselves and get quite large. As the numbers of toads increase from breeding, the food resource never reaches its pre-toad levels and therefore, the toads' size and their food supply acheive a "compromise". Certainly the largest toads still found in Cairns come from the suburbs which back onto bush and, therefore, have more plant life to feed more insects.