The state government has confirmed its discovery of an outbreak in Perth's Alfred Cove of the Queensland fruit fly, ending WA's time as one of only three states able to declare itself free from Australia's most damaging fruit pest. 
Department staff found two male Qfly, now present in all other states except South Australia and Tasmania, in the Alfred Cove residential area on   November 18 in surveillance traps and quickly installed, catching another four male flies on   November 23 within 800 metres. 
"[The Department of Agriculture and Food WA] is meeting this afternoon to discuss options available. The outbreak may have trade implications," an email to industry stakeholders said after the outbreak was confirmed. 
Qfly attacks more than 200 varieties, including those vulnerable to the long-established Mediterranean fruit fly, but also those previously invulnerable to Medfly, including chillies, tomatoes, strawberries, avocados, passionfruit and some vegetables.
Department entomologist Darryl Hardie said the department had a trapping grid across the whole metropolitan area, with traps every 400 metres in high-risk areas. 
For an outbreak to be declared five males had to be found within 2 kilometres of each other within two weeks, and the system had found six flies within 800 metres within four days - in other words, had "lit up like a Christmas tree". Department staff will have placed up to 50 more traps in the immediate area by the end of the day to determine how far the pest had spread. 
He said the implications for trade with Tasmania and South Australia, now the only Qfly-free states, were still being assessed. 
Dr Hardie said that quantity of flies suggested several pieces of fruit had been brought into the state. He was not surprised they had been found in a residential area because those were the typical end points for people travelling interstate. 
"When people smuggle fruit in from over east they just don't realise the potential consequences," he said. 
"They go home and find a bit of maggoty fruit in their suitcase and just chuck it in the garden. That's a pretty likely scenario." 
Qfly has previously been detected and then eradicated in Perth in 1989 (Nedlands area), 1995 (Lathlain) and 2011 (Highgate). Dr Hardie has weathered all these outbreaks, and said the 2011 outbreak had cost the department hundreds of thousands of dollars to bring under control. 
But that is small change compared to what it would cost the WA horticultural industry if the outbreak grew beyond its control - the national Plant Biosecurity Cooperative Research Centre Fruit estimates that fruit fly costs the nation about $300 million a year in control and lost markets. 
The CSIRO website says that Qfly is threatening the nation's $6.9 billion horticultural industry, which relies on both domestic and international trade. 
Farmers have until recently used the pesticide fenthion to help prevent outbreaks of Qfly, but after a long period of review, the Australian Pesticides and Veterinary Medicines Authority banned the chemical because of public health fears. 
The phase-out has already affected West Australian growers battling Medfly.
A $22 million research consortium, including Horticulture Australia, CSIRO Biosecurity Flagship and Plant and Food Research Australia has been established to develop a male sterile Qfly to manage damaging Qfly populations, a technique that has been piloted in WA with some success against Medfly. 
The department will provide further advice to industry and the community as more information became available.
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