'Snails pace' research proves effective in curbing pest

By / 4th of December, 2014
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Remote video cameras on Graham Hayes’ Warooka grain farm in the Yorke Peninsula of South Australia are poised to revolutionise baiting of crop-diminishing snails.

New footage recorded around the clock at his property has revealed a new understanding of the feeding and mating patterns of the snails, indicating that the gastropods are laying eggs and feeding following lighter rain events, and not exclusively after significant rain events as former research suggested.

“If people have snails, they can now get the best results from the bait, by baiting at the right time. And I can guarantee that will be a lot earlier than they’ve been doing in the past,” Hayes said.

“It’s a step in the right direction towards breaking the life cycle of this chronic pest.”

The innovative project is led by Northern and Yorke Regional Landcare Facilitator Michael Richards, who has been monitoring the movement and activity of round and conical snails through ‘SnailTube’.

The project is supported by the Grains Research and Development Corporation (GRDC), South Australian Research and Development Institute (SARDI) and the University of South Australia.

Three online cameras are currently in use across South Australia; one in the south-east of the state, one at Minlaton and one at the Hayes’ farm at Warooka. A further six smaller cameras are located at Warooka, Stenhouse Bay, Eyre Peninsula and in the state’s south-east.

The cameras have revealed that mating is occurring from March to April depending on the weather.

“Snails began feeding in mid-February at 90 per cent relative humidity, often during damp overnight conditions, and then would shut down during the drier daylight period,” Richards said.

“Since March 18, 2014, snails started to feed at 80 per cent humidity, and they have also been observed mating since this date on Eyre Peninsula, Yorke Peninsula, Langhorne Creek and in the south-east.

“This is the first time that snail activity has been monitored so closely in this way and we are starting to gain a better understanding between rainfall events and snail feeding activity.”

This new insight into the feeding and breeding patterns of snails will hopefully be a ‘game changer’ for Hayes and other farmers who’ve battled with the infestation of these devastating pests for decades.

“They may be considered a unique delicacy to consumers dining in high-end French restaurants, but to me they’re the bane of my existence,” Hayes said. “They’re the greatest pest that we’ve ever had to deal with. Snails have been in this district for more than 100 years.”

Hayes, affectionately known around the traps as ‘The Snail Man’, has farmed snail infested country in the southern part of the Yorke Peninsula his entire life.

He crops 1500 hectares in a base rotation of wheat, barley, lentils, canola and the soil types range from stony, heavy country to grey calcareous sand.

With an average rainfall of 470 millimetres, accompanied by seawater surroundings exempt from the heat and frost of inland South Australia, Mr Hayes’ farm is a prime breeding environment for snails.

Round and conical snails devastated the property in 2000, costing Hayes and his business $143,500 in yield loss.

With grain receival depots allowing just one snail per 200 grams, Hayes has also been involved in GRDC funded projects supported by the Yorke Peninsula Alkaline Soils Group (YPASG), SARDI and the University of SA to develop methods to ensure local grain meets receival standards.

“We’ve tried absolutely everything available,” he said.

“We’ve incorporated all of the techniques outlined in The Bash’Em Burn’Em’ Bait’Em manual into our farming system here in Warooka - including cabling after harvest, laying out metaldehyde baits, burning stubble and grain cleaning - with varying degree of impact.”

Published in 2003, the manual brings together the results of more than 15 years research and over one million dollars of investment by multiple organisations, including GRDC and the South Australian Grains Industry Trust (SAGIT).

In more recent years, Hayes has been working with Charles Sturt University (CSU) supplying snails for research in the attempt of identifying a permanent solution to snails, including a native nematode.

“Nematodes are like worms and they live in the soil and there's a whole range of different ones. There are some that attack plants, some that eat bacteria, and the ones that we have here that attack snails. They burrow in the snail’s stomach and kill the snail by poisoning its blood,” Hayes said.

The introduction of nematodes on to Hayes’ property in 2012 showed some initial encouraging signs, but ultimately, due to the unfavourable climatic conditions for nematodes, the experiment failed.

“The soil was too dry for the nematodes to survive, and in those areas where they were released, there has been no reduction in snail numbers,” he said.

Two years on and snails are still by far the biggest issue for Yorke Peninsula farmers, but with this latest remote camera technology, there is light at the end of the tunnel for the The Snail Man.

“Two years ago, wet summer, we used 30 tonne of bait, and in some areas we baited three times,” he said. “But the snails still demolished 130 hectares of lentils and we know now it’s because they laid eggs before we baited.   

“Hopefully sometime sooner rather than later, we can break that life cycle. So if we can break that life cycle and eliminate 100 per cent of the snails once, well they’re not going to come flying back in.”