Grains Convo

Kate Muirhead, Dr Kym Perry, Lizzie von Perger, and Svetlana Micic place snails with parasitic flies into release buckets as part of a biocontrol trial at Wellstead in the Great Southern
National collaboration effort to enhance snail management solutions

Mediterranean snails, specifically the small pointed snail or conical snail, Cochlicella barbara, are present in many areas, especially in the broadacre regions of Western Australia (WA) where they feed on crop plants and as grain contaminants.

Effective management of these snails requires a multi-faceted approach, which includes baiting and stubble management strategies that reduce snail habitat.

More tools in the toolbox are needed to curb snail populations especially snails present in non-crop areas of the farm, that can then move into cropped paddocks.

Australian-bred parasitoid flies have been released to help control snail pests and protect crop yields, quality and growers’ profitability.

The flesh fly (Sarcophaga villeneuveana), originally introduced to Australia 20 years ago as a biocontrol agent from France, only targets the grains pests pointed snail (Cochlicella acuta) and small pointed snail.

It was originally sourced from Montpellier in France, and subsequently mass-reared and released by the South Australian Research and Development Institute (SARDI) and CSIRO in South Australia's Yorke Peninsula, where it has since established and proliferated.

Research in South Australia has found parasitism levels have exceeded 30% to 40% in localised habitats in recent years, indicating this fly can have an impact on snail populations.

This fly has now been introduced in select areas of WA.

This bio-control program is part of a larger 4-year project by SARDI and the University of Adelaide, is an investment of the Grains Research and Development Corporation (GRDC).

The Department of Primary Industries and Regional Development (DPIRD) and South East Premium Wheat Growers Association (SEPWA) have joined forces with SARDI to release the flies for the first time in WA.

Releases have occurred in the Albany and Esperance port zones.

The goal is to determine if this parasitic fly can establish in WA.

To date, over 1,000 flies have already been released over 4 locations.

These sites will be monitored to see if this fly can survive and thrive under WA’s dry summer conditions.  

Safeguarding Western Australian agriculture

All of the pest snails found in WA's crops have been introduced from Mediterranean climes of Europe.

Legumes and canola, especially, recently germinated seedlings, and leaves are most at risk from snail damage.

Snails can also increase harvest costs as they can be a contaminant of grain at harvest, leading to the requirement for grain to be cleaned before it is delivered to grain receivals.

The prevalence of snails has increased in broadacre cropping in WA with the use of minimum tillage and stubble-retention practices.

Monitoring and expansion

Biocontrol offers an additional avenue to curb snail populations alongside baiting and paddock management strategies.

The flies can also reduce snails in the non-crop areas of the farm.

DPIRD Research Scientist (Entomologist) Svetlana Micic said further releases are planned at in non-crop areas to bolster populations and give the flies every chance to establish.

“The team anticipates that if the fly established, it will persist in the areas in which they have been released. Flies will be spread through additional breeding and release programs.

Regular monitoring will gauge the success of establishment, potentially paving the way for expanding the program across the WA Grainbelt.

While acknowledging that biocontrol isn't a cure-all, it can be used as one way to help growers grappling with high snail populations,” she said.

This trial builds upon GRDC-funded research led by CSIRO and SARDI to explore factors influencing fly parasitism of pest snails on South Australia’s Yorke Peninsula.

Funding partners/project collaborators 

Grains Research and Development Corporation (GRDC)
South Australian Research and Development Institute (SARDI)
University of Adelaide
Stirlings to Coast Farmers (SCF)
South East Premium Wheat Growers Association (SEPWA)

More information 

Click here to read the DPIRD media release on Fly biocontrol released to control farm snail pests
Click here to read more on Identification and control of pest slugs and snails for broadacre crops in Western Australia


Svetlana Micic
DPIRD Research Scientist (Entomologist)
P: (08) 9892 8591