Feeding strategies of the giant African snail Achatina fulica on papaya in Samoa
The giant African snail (Achatina fulica) is a widely introduced invasive land snail species, and is considered an important agricultural pest in several regions of the world including in the south Pacific. In Samoa, A. fulica is a major pest that feeds on various crops of economic importance, including papaya. This study investigated the feeding strategies of A. fulica and the damage caused to papaya through field and laboratory trials in Samoa. Unripe mature fruits were sampled to assess snail damage. Results showed heavy snail infestation; on average more than two snails were recovered per papaya tree. The mean number of snails per plant decreased with the height of the plant. Snails inflicted primary damage through feeding that led to abrasions on more than 80% of fruits and indirectly caused fungal contamination through their faeces (93%) and slimy marks. Snail feeding damage induced premature ripening of papaya fruits. In the host choice tests, the snails preferred to feed on papaya than tomatoes; however, they showed equal preference to papaya and cabbage in the field trails. Smaller snails were voracious and ate more papaya leaves per unit of body weight compared with larger snails. Snails were found to be good climbers, and 60% of the snails released near the papaya tree trunk were able to reach the papaya fruits on the tree. However, climbing was less prevalent on wet/rainy days.
Kant, R. and Diarra, S.S. (2016). Feeding strategies of the giant African snail Achatina fulica on papaya in Samoa. Acta Hortic. 1128, 229-236
snail damage, feeding preference, choice test, fungus growth, antifeedant, snail faeces