Green snails

Green snails (Helix aptera) have been identified from a lucerne paddock near Cobram, in the Northern Country district of Victoria. In Australia, this is the first confirmed case of this pest snail outside of Western Australia. Senior Plant Standards Officer, Harvey Cleaver (VIC DPI), said the green snail became established in the Perth area in the 1980’s.

Surveys in close proximity to the lucerne paddock near Cobram have identified green snails present at a further two sites. The green snail has a wide host range including peas, beans, wheat, lupins, pasture grasses and native plants. Harvey says lucerne plants in the affected paddock at Cobram were noticeably damaged and growth was being ‘held-back’. The paddock has been baited and a very good level of control was achieved.

The distribution of the green snail in Western Australia is relatively restricted. In addition to Perth, snails have been recorded in rural locations approximately 200 km south and 120 km north of Perth. They are predominantly found on horticultural crops including cabbages, cauliflowers, lettuces, peas and beans, and on roadside volunteer cereals and grasses. Green snails originate from southern Europe and north Africa, and are considered somewhat of a local food delicacy. Technical officer, Marc Widmer (DAFWA), says an eradication program was established in Western Australia but has now ceased.

The green snail is slightly smaller than a common garden snail and has an olive green shell with white coloured flesh. They can reach densities of 800-1000 per square metre in extreme situations. Like some other snails, the green snail remains dormant through the summer in dry situations. However, unlike other snails, it burrows into the soil before becoming dormant, which makes baiting ineffective during this time. Interestingly, green snails have not become a significant pest of broad-acre crops in Western Australia.

The Victorian Department of Primary Industries is continuing to investigate this occurrence. A temporary restriction on the movement of plant material and machinery around the affected area is presently in place. If you have observed snails that you think could be this species, contact the Victorian Department of Primary Industries by phoning 136 186.