Fire ants are on the march across southeast Queensland despite the hundreds of millions of dollars being spent to halt their spread.

The latest figures show that in just a matter of months the number of nests has almost tripled to around 9,000 and more than 70 per cent are in the Logan area.

Biosecurity Queensland maintains its eradication program remains on track but whistleblower Pam Swepson tells Mark things have long been out of control.

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