Australian flood: Next comes the rat plague

Sean Parnell The Australian 6 Jan 11;

KANGAROOS, snakes and other native animals escaping Queensland floodwaters now find themselves sharing higher ground with humans and livestock.

While the increased presence of venomous creatures has added another element of danger to the rising floods, in the long term there is also the threat of rat plagues as some species thrive where others have either been killed off or forcibly relocated.

Environmental scientist Noel Preece has conducted one of the few studies of the effect of floods on Queensland wildlife. He sees some similarities between the current disaster and flooding in the Gulf of Carpentaria two years ago.

"All the river floodplain areas were inundated for months (after the Norman and Yappar rivers flooded) and it had a really significant effect on the ground-dwelling fauna," Dr Preece said yesterday.

"All the small mammals and reptiles just disappeared -- it was devastating."

Dr Preece said animals able to move quickly could only survive if they had somewhere to go -- much of the current flooding is over vast, flat areas -- and even those capable of climbing trees could find themselves without food and threatened by predators.

Like bushfires, floods leave some areas uninhabited, even killing off native grasses, while there may be a disproportion of species elsewhere, which takes time for nature to address.

"It just wipes the slate clean for a period of time," Dr Preece said.

"It's an unsettled period because some animals, the rats for instance, can go into plague proportions once the floods have gone."

Queensland Parks and Wildlife general manager Clive Cook said that during the floods it appeared different species had become more tolerant of each other, despite being confined to smaller areas. Still, health authorities have dealt with an increase in snake and spider bites, and expect mosquitoes to become more of a problem.

Mr Cook said a population of northern hairy-nosed wombats near St George had so far survived. There are also flow-on effects, such as sediment destroying seagrass beds and leaving dugongs to starve.