Tasmania's opium poppy farmers have been offered an explanation for mysterious crop circles in their fields which have become part of local lore: They're caused by drugged-up wallabies which get blasted on the plant heads and hop around in circles.

That's according to Taz attorney general Lara Giddings, who explained that she'd discovered the industry had "a problem with wallabies entering poppy fields, getting as high as a kite and going around in circles".

Rockliff added that the principal risk associated with animal alkaloid abuse was contamination of the meat, but he noted: "There is also the risk to our poppy stocks, so growers take this very seriously but there has been a steady increase in the number of wild animals and that is where we are having difficulty keeping them off our land."

Tasmania accounts for 50 per cent of all the world's opiate supplies, local paper The Mercury notes. Its main products are codeine and thebaine. ®

Related stories

• Canuck record labels accuse tunesmiths of smoking opium (8 January 2008)
• 'Unusually frisky' deer blow lid on marijuana plantation (2 July 2007)