DRY conditions have kept snail numbers low this season, but growers should stay alert, with populations likely to rebound quickly if weather conditions change.

This is the message of University of Adelaide senior entomology researcher Dr Kym Perry, who says the unusually dry weather has provided ideal conditions for early snail control, ahead of the main breeding period.

“The lack of season-breaking rains in early 2024 likely limited snail breeding, which usually begins in early autumn and extends into mid-winter,” he said.

Snail mortality has also been higher than usual, with heatwaves and hot, dry weather over spring and summer reducing survival rates.

“Temperatures of 60 degrees Celsius can kill snails instantly, and on a 40C day, ground-level temperatures can exceed 70C,” Dr Perry said.

“A lack of green summer weeds has further reduced snail survival.”

However, light rains and dewy mornings can quickly trigger overnight snail activity.

Dr Perry warned that growers must be ready to bait at short notice, as moist conditions encouraged movement and feeding.

“Snails are extremely hungry after summer dormancy and, with fewer alternative food sources, bait pellets are more likely to be encountered and consumed,” he said.

Dr Perry recommended baiting early, before snails began laying eggs. 

At this stage, snails spend several weeks feeding and maturing their reproductive organs in preparation to breed.

“A well-timed bait application can achieve high levels of control,” he said.

“Kill as many as you can before they start laying eggs.”

When baiting, select your preferred product and broadcast pellets evenly using a calibrated spreader. 

Apply when snails are expected to be moving — ideally when ground-level relative humidity exceeds 95 per cent — and aim for at least 30 bait points per square metre.

Reapply bait as needed and always follow label rates.

For more, see GRDC’s PestFacts, dated April 10, 2025.