Spider plagues takeover after Tasmanian floods

The clever way in which spiders survive flooding events is still being witnessed by Bass Highway motorists as they travel between Westbury and Deloraine.

Launceston entomologist Simon Fearn said the phenomenon was nothing unusual and just one of the strategies that ground-dwelling spiders employ when dealing with floods.

He said that hundreds of thousands of little wolf spiders normally live in Tasmanian agricultural pasture, largely unseen day to day.

Mr Fearn said as water rises during flood, thousands of them will climb up on trees and shrubs for survival.

"And then what they do is spin these silk rafts to make it hard for birds to attack them," he said.

"If these small spiders find themselves stranded somewhere, they stick their end up in the area and let out a strand of silk. As the breeze catches that silk, it picks them up and carries them away on the wind.

Spider plagues at Westbury. Picture: Ken Puccetti

Spider plagues at Westbury. Picture: Ken Puccetti

"You can then have hundreds of thousands of spiders doing that and of course all these strands of silk end up getting stuck on the tops of grass, trees and shrubs.”

Mr Fearn said that larger spiders that get caught in floods could seal up their burrows and trap air in there, staying underwater for days before they need to leave.

"And because lots of large spiders are covered in fine hairs, those hairs will trap air underwater so the spiders can float to the top of the water," he said.

"Ground-dwelling spiders have lots of strategies to deal with floods."

Have you found a spider plague? Email online@examiner.com.au