Question

What are cane toads effect on the food chain?

Answer 1

ANSWER....

Cane Toads eat almost anything they can swallow, including pet food, carrion and household scraps, but most of their food is living insects. Beetles, honey bees, ants, winged termites, crickets and bugs are eaten in abundance. Marine snails, smaller toads and native frogs, small snakes, and small mammals are occasionally eaten by Cane Toads.The tadpoles of Cane Toads eat algae and other aquatic plants which they rasp off with five rows of tiny peg-like teeth. They also filter organic matter from the water. Large tadpoles sometimes eat Cane Toad eggs.

Answer 2

The toxic cane toad introduced to Australia in the 1930s is causing ripples through the ecosystem in ways rarely seen when invasive species spread.

We know that toads poison their predators, but this seems to allow other prey species to bounce back. It is a rare piece of solid evidence for an invasive species causing what is called a “trophic cascade” in the wild, researchers say, where killing off top predators has unexpected effects throughout an ecosystem.

The toads arrived in 1935 from the Amazon as an experiment to control a beetle that devastated sugar cane crops. It didn’t work. But the initial 102 young toads quickly multiplied until there were hundreds of millions, stretching from coast-to-coast. In places, they form seething masses of up to 2000 toads per hectare. They have even evolved to become better invaders by growing longer legs and being more aggressive, driving some species to extinction in local areas.

Simon Clulow from the University of Newcastle in Australia and his colleagues tracked the toad population as they conquered new territory in Western Australia. This was a unique opportunity to track the initial effects on other animals in the area. They measured the populations of three species of predatory water monitors that eat the toads, and the crimson finch Neochmia phaeton, which are prey for the monitors.

The toads wiped out about half of the water monitor population within five years. That had a knock-on effect on crimson finches: the proportion of surviving fledglings jumped from 55 per cent to 81 per cent.