I think you were on the wrong roads!! The flying cane toad is
well established now on the Sunshine Coast, but not yet in plague
proportions. I see them daily in small numbers at Landsborough and at
Beerwah, both railway/corridor towns behind the coast.Others see them
regularly at other towns, incl. Nambour.
As Roy S. mentioned , the shires of Caloundra, Maroochy, and I
think Noosa and Caboolture are investigating ways of controlling their
spread.A public meeting last year at Maleny attracted around 100 people
(mostly non-birders, but environmentally aware) to discuss the spread.
Fauna Watch, a local Sunshine Coast volunteer-based surveying
group is currently receiving regular data to monitor their spread.If Keith
H., Valda McL, or Jill C. are on birding-aus they may have more info.
I've not yet seen them up on the Blackall Range (the mountain
range behind the Sunshine Coast) but they have (apparantly) been reported.