Remote Snail Sensing

Remote Snail Sensing

Project Brief

Increasing snail populations are damaging emerging crops and pastures, lowering produce quality & causing management practices which increase erosion risk. Controlling snails before egg laying is critical for effective treatment.

Ag Ex is working with farmers, researchers and advisors to develop, demonstrate & apply remote sensing monitoring techniques to fill key gaps in knowledge of snail reproduction triggers & nocturnal behaviour.

Collated information & "control alerts" developed, will be used to assist 1,150 farmers with achieving effective snail control before egg laying, optimizing snail control. Concise, timely alerts and use of effective 24 / 7 monitoring techniques will ensure ongoing benefits.

Project Duration

March 2013 – July 2013    Ongoing funding is currently being sought.


DEWNR Sustainable Dryland Agricultural Initiative

Project Area

Northern & Yorke NRM Region

For more information contact

Michael Richards: 0427 547 052 or

Project Progress

Updated 30th May 2013

Have you checked your paddocks for snail activity since the rain? White Italian snails are egg laying with each rain on Southern Y.P. Conical snails have been mating for several weeks.

The good news is egg clusters appear smaller than usual, this is most likely due to the hot dry summer on Southern Y.P.  See attached snail eggs photo.

Check paddocks now; If you have live snails, bait as soon after seeding as possible, to prevent more egg laying.

Bait is better applied before rain events, don’t wait for rain to bait.

Snails will be active with overnight moisture will find the bait.

Check for live snails six days after baiting.

Pay special attention to Canola and Pulse crops as;

  • they can be more sensitive to damage
  • snail numbers can rapidly increase in these cops
  • contamination is likely to cause more problems at harvest

Recommended Metaldehyde Bait application rates for standard strength baits are;

  • 5 kg / ha of bait for less than 80 adult snails / sq. metre
  • 10 kg / ha of bait when there are more than 80 adult snails per sq. metre
  • Rule of thumb
  • 5 kg of 4 mm Bait equates to 5 baits / sq. metre
  • 5 kg of 2 mm Bait equates to 12 baits / sq. metre

If snails are invading from paddock perimeters with high snail populations use the 10 kg / ha rate for the first 100 metres in from the paddock perimeter.

Want to know how to find snail eggs?

Look for a small pile of disturbed as in the attached photo title Snl Soil Pile Egg laying. Often the hole shown in the photo is filled in.

Latest Observation

Snails have been on the move in the Warooka area following light showers in late March.

White Italian Snails were observed pairing up and mating following light showers on the 27th & 30th of March.

White Italian Snails started to pair up within one hour after 1 to 2mm showers.

Don't leave it too Late to Bait

  • For effective snail control, snails need to be controlled prior to egg laying as each snail can lay 400 eggs.
  • Egg laying can commence within 14 days of mating.
  • Snails will delay egg laying until the soil is moist.
  • Check paddocks now for snail numbers and snail movement.
  • Squash a snail today. If they are moist and juicy, they are ready to go.
  • Farmers are having improved results from applying bait before rain events.
  • Snails are soft matter feeders, coming rains will soften bait make it more palatable to snails as they become active.
  • Spraying out green plants before baiting will increase snail mortality.

 The Bait Facts

  • Metaldehyde breaks down with Ultraviolet light.
  • Lower UV levels in April ensures Bait will last over 4 weeks
  • Bait applied now will last until seeding, in paddocks which aren't cultivated.
  • Check evenness of bait application across the spreading width.
  • Adjust spreader settings as per manufacturer recommendations for bait application.
  • Longer pellets will increase variability of bait flow and variation in uniformity of spreading pattern.
  • If you have over 80 adult snails per square metre apply 10 kg of bait per Ha (15% active metaldehyde bait)
  • For 50 adult snails per square metre apply 5 kg of bait per Ha (15% active metaldehyde bait)

Rule of thumb

  • 5 kg of 4 mm Bait equates to 5 bait pellets / sq metre
  • 5 kg of 2 mm Bait equates to 12 bait pellets / sq metre


In areas where snails are mating, Egg Laying could occur within several days of the next moisture event, which wets the soil to a depth of 50mm

Management options

  • Check snails now for signs of movement.
  • Border bait paddocks now to prevent infiltration.
  • Apply bait in paddocks which will not be cultivated or dry sown.
  • Five to six days of snail movement will ensure uptake of bait.
  • Snail activity will increase as temperatures drop and humidity increases.
  • Check baited areas within 6 days of snail movement following baiting.
  • Count live snails, dead snails are harmless.