Bought into Queensland in 1935 to combat the sugar cane beetle, cane toads have now spread far and wide, even invading Kakadu National Park in the Northern Territory. They have no known natural predators and viruses from their native Venezuela are lethal to some of our native frogs. So CSIRO researchers have brought them to Canberra to try to stop their spread with gene technology.

"Environmentally they're bad, but they do grow on you."

The toads are well looked after, in a home heated to 27 degrees and they receive a weekly bath.

"I generally leave them in there for an hour or an hour and a half. This gives them plenty of time to shed the old skin and clean up. They certainly appreciate it."

Then after the bath comes the romance. The toads are injected with hormones to get them in the mood and then left overnight to mate.

"We just put one male and one female in each tank and you come in the next morning and there's thousands of eggs wrapped in a nice concentric circles around the rock. Then we transfer them in a smaller tank and the tadpoles start forming."

So far the team has just been assisting nature, but now the real science begins. This tadpole is being injected with an adult toad protein called Betaglobin, in the hope that its antibodies will reject it. If that happens then its antibodies should also reject the tadpole's natural Betablobin when it occurs, stopping it from turning into an adult.

"We're injecting them with a possible protein that could be used in halting the metamorph of the tadpole into the toadlet."

Once the method is perfected, the gene that stops the maturing of the toad will be isolated and introduced into the toad population, before they get to Canberra by themselves.