Sunday, August 30, 2009

Brown Tree Snail

Recently, the rarest land snail in Singapore was sighted in great numbers. They were all congregated on two trees in the Singapore Botanical Gardens (SBG), several of them mating with some observed among leaf litter. This is the Brown Tree Snail (Amphidromus inversus inversus).

This critically endangered snail is mainly arboreal, inhabiting trees within primary forests preferring humid and damp conditions. Only one population survives in Singapore, and that's in SBG. We are not sure how big the population is but I believe it is hanging on by a thread considering the snail is found only within a small area in SBG. My knowledge on land snails are limited so I wonder why its found only at SBG and not in our forest reserves too. As mentioned in the Singapore Red Data Book, a study on population size is long overdue and a concerted effort must be made to introduce a second population in the nature reserves.

We have five Amphidromus species and subspecies in Singapore. The other one that is also rare is the Green Tree Snail (Amphidromus atricallosus perakensis) from the nature reserves.
As I took the pictures, passerby walked past. Some gave me curious glances but most ignored me. Many Singaporeans don’t know we have several species of flora and fauna eking out a last stand here. Many of these species are unspectacular and inconspicuous unlike the charismatic Colugo or the iconic Oriental Pied Hornbills. The extinction of a snail would hardly make a dent in an urban dweller’s life. But it’ll be a loud silent scream from our natural heritage.

Snails in the pictures are individually marked for research purposes.

Pictures taken at: Singapore Botanical Gardens, August 2009.


Lok, A. F. S. L. & S. K. Tan, 2008, ‘A review of the Singapore status of the Green Tree Snail, Amphidromus atricallosus perakensis Fulton, 1901 and its biology’, Nature In Singapore, vol. 1, pp. 225-230.

Davison, G. W. H., P. K. L. Ng & H. C. Ho (eds), 2008. The Singapore Red Data Book: Threatened Plants and Animals of Singapore. 2nd Edition. The Nature Society (Singapore), Singapore.