State battles fruit fly threat
Tasmania’s biosecurity status, described as globally unique, faced its gravest challenge in decades after an incursion by Queensland fruit fly.
Outbreaks on Flinders Island and along a swath of the main island's Bass Strait coastline threatened the State's certification as fruit-fly free, which enables fresh produce to be exported without fumigation.
The Minister for Primary Industries, Jeremy Rockliff, said: “I believe this incursion needs to be managed in a similar way to a natural disaster.”
The problem first emerged on Flinders Island in January when fruit fly larvae were found in apricots from trees on a private property at Trousers Point.
While biosecurity officers were at the site considering treatment options and taking steps to determine the source, more larvae were found 20km away at Lady Barron.
Although Flinders Island is not a fruit exporter, a control zone was established so that the movement of fruit and vegetables could be restricted and monitored.
Two weeks later, a second exclusion zone had to be defined after fruit fly larvae were detected at Spreyton, again on non-commercial apricot trees.
This was a more complex situation, with a Greater Devonport Control Zone taking in many commercial fruit and vegetable production sites and affecting several exporters.
It had to be expanded twice in February, firstly along its eastern margin as fruit fly were detected close to its boundary; then on a more drastic scale as an infestation was confirmed at George Town, more than 100km to the east.
Fruit fly became a potentially state-wide issue on 21 February when a nectarine shipped in from Victoria and certified by an accredited facility there as "fruit fly-free" was found to be infested with larvae.
The discovery by Biosecurity Tasmania during a routine check in a Devonport supermarket prompted a recall from retail shelves across the State of all produce that had passed through the Victorian facility.
Mr Rockliff described the apparent failure of Victorian authorities to catch the infected produce before it arrived in Tasmania as "frustrating".
He said: "We will get to the bottom of exactly where the failure occurred in the fruit fly certification process."
Authorities said the recall did not involve tonnes of fruit, but Tasmanians were urged to check any recent purchases and to double wrap any suspect waste in plastic before disposing of it.
Potential hosts for fruit fly include apples, apricots, bananas, blackberries, capsicums, cherries, figs, grapefruit, mulberries, nashis, nectarines, oranges, peaches, pears, plums, raspberries, strawberries and tomatoes.
One medium-sized retailer sent back 12 pallets of fruit valued at $60,000 to Victoria.
The General Manager of Biosecurity Tasmania, Dr Lloyd Klumpp, said: "We are undertaking further investigations with interstate authorities, including any relationship between this Victorian treatment facility and other Tasmanian detections of fruit fly this summer."
Mr Rockliff said: "It now appears that there may have been a failure in the fruit fly-free certification process on the mainland, rather than an issue with processes in Tasmania.”
The Tasmanian Farmers and Graziers Association (TFGA) urged the Government, to focus on the task at hand — the eradication of fruit fly — and not be distracted by the apportioning of blame.
“Fruit fly infected fruit from Victoria has been located, but this does not mean that it is the origin of the Tasmanian incursions or the only origin,” TFGA head Peter Skillern said.
“Either way, this issue points to the critical need for Tasmania to invest heavily in our own biosecurity, a position that the TFGA has been advocating strongly for a number of years."
The Government, which was in caretaker mode at the time, promised Biosecurity Tasmania "a blank cheque" to respond to the issue as it needed to.
In the midst of an election campaign, the Premier, Will Hodgman, and the Leader of the Opposition, Rebecca White, agreed that quick eradication of the pest was vital to Tasmania’s reputation.
Mr Hodgman said: “We need to make sure that the on-going effort to protect Tasmania’s strong brand … and ensure that we can reinstate Tasmania’s status is receiving critical priority."
Ms White said: “It is that big challenge we need to tackle to preserve the brand integrity that Tasmania has. [The brand] provides a value for all Tasmanian products leaving this State.”
The Executive Director of Brand Tasmania, Robert Heazlewood, said: "This issue is not only vitally important for Tasmania's agriculture sector, which has been growing quickly on the back of massive investment driven by irrigation.
"A lot of that investment has gone into horticulture, so a lot of enterprising people could be hurt if we don't get on top of this.
"That's one side of this situation, the other is that this State's biosecurity status is one of the foundations of our brand.
"One European fruit grower described this advantage of ours as 'unique in the world'."
The Mercury editorialised: "Brand Tasmania is the biggest selling point we have. Protecting it is vital to our future prosperity. Our brand is clean, green, friendly — and, in agriculture, basically disease-free…
"Ensuring fruit fly does not have any chance to get a foothold in our State is critical to the future of a very important industry.
"But it’s also critical to the future of Tasmania, in that being fruit-fly-free is just one of the boasts we can make to support the important Brand Tasmania message — the message that, in an increasingly populated world, will sustain our [islands] into the future."
After years of negotiations with Asian trade authorities, Tasmanian fruit and vegetable producers have been able to claim premiums in many markets for their fumigation-free products.
They have access to consumers in Japan, South Korea, the United States and China that are out of reach for other Australian growers.
Taiwanese authorities were the first importers to react to news of the outbreak, announcing that they would not accept produce from either of the exclusion zones.
Braddon Labor MP, Justine Keay, told Federal Parliament that a cherry grower within the original Spreyton control zone had lost market access to China and was being forced to sell fruit into Hong Kong at half price.
On the biosecurity front lines, an all-out effort was underway.
An intense baiting and trapping program was launched inside the control zones with 80 staff working over the last weekend of February.
Biosecurity Tasmania routinely deploys about 100 fruit fly traps at random locations around the State and inspects them weekly to ensure the integrity of the fruit fly-free claim.
This program was quickly expanded to 1,000 traps.
Previously, the traps have rarely delivered anything untoward and it is generally accepted that an occasional fruit fly invader would not survive Tasmania's winter.
However, even a temporary summer incursion of the pest, which is common across continental Australia, is clearly disruptive to the $50 million-a-year fruit-export business.
The impact of the incursion widened with the second expansion of the Spreyton control zone to span the mouth of the Tamar River and include more than 30 vineyards, along with many other horticultural businesses.
Wine Industry Tasmania's Sheralee Davies said: "We are working very closely with the impacted businesses so that they understand the implications and we do everything we can to make sure that we're not spreading fruit fly any further."
Ms Davies said she was in constant communication with producers and felt confident they would be able to proceed with harvesting.
She said a protocols agreement brokered with Biosecurity Tasmania meant grapes could still be transported through and from the control zone under agreed conditions.
Wine grapes, like other fruit, must either have been cold sterilised for several days or fumigated before leaving the control zone.
As some Tasmanian apple producers began harvesting in late February, they were able to negotiate a protocol for the use of Taut Liners (curtain-sided trailers) to transport their fruit through the control zone.
Before the control zone expansion, Mr Rockliff told a media conference: "We are going to destroy these little buggers".
He announced a $2 million rescue package for fruit and vegetable producers caught up in the original control zone.
Available to affected growers, distributors and retailers, the package includes:
- Financial assistance for those in the control zone suffering financial hardship resulting from the implementation of fruit fly prevention measures;
- Assistance with costs required with meeting fruit-treatment requirements;
- Industry assistance to source new interstate markets for producers within the control zone;
- Assistance package to help with changes that may be required for packaging; and
- Assistance with fruit clean-up and disposal.
Things didn't always go to plan as Biosecurity Tasmania intensified trapping and other eradication measures.
Between 30kg and 40kg of apricots, allegedly from within the Spreyton control area, were seized by officials at the Wynyard Foreshore Market.
Then the Department of Primary Industries, Water and the Environment (DPIWE) was forced to suspend fumigation it had just started at Devonport Airport when four staff reported ill after working with methyl bromide.
DPIWE reported the incident to WorkSafe Tasmania and initiated its own investigation.
One of the workers involved reported to Mersey Hospital and was kept in overnight for observation.
Meanwhile, a DPIWE spokesperson praised the “fantastic vigilance from the community”.
People are required by law to report any signs of fruit fly on their properties.
Many of the scores of reported sightings turned out to be harmless vinegar flies which are common in Tasmania.
Aside from fruit fly, many other agricultural pests and diseases are normally absent from the State.
These include spotted-wing drosophila, potato cyst nematode, fire blight, tobacco blue mould, mad cow disease, foot and mouth disease, rabies and rinderpest, the varroa mite that attacks beehives, and spinning disease that infects salmonids.
Freedom from these threats enables farmers to operate with relatively low levels of chemical input and their products seldom require fumigation before export.
The Primary Industry Biosecurity Action Alliance was formed in 2016 to campaign against Australian legislation that threatened to impose a one-size-fits-all approach to national biosecurity and did not properly address Tasmania’s special needs.
The alliance’s campaign was ultimately successful.
As it said in a 2016 statement: "Tasmania’s freedom from catastrophic pests and diseases is not ours to trade away. Biosecurity is inter-generational."
Image courtesy of Biosecurity Tasmania
8 March 2018, Edition 192