Lord Howe Flax Snail

Taxobox
name = Lord Howe Flax Snail
status = CR
status_ref = [IUCN2006|id=17447|title=Placostylus bivaricosus|year=1996|assessors=Ponder, W.F.|downloaded=2007-11-17]
status_system = iucn2.3
regnum = Animalia
phylum = Mollusca
classis = Gastropoda
subclassis = Orthogastropoda
superordo = Heterobranchia
infraordo = Stylommatophora
ordo = Pulmonata
subordo = Eupulmonata
familia = Bulimulidae
genus = "Placostylus"
species = "P. bivaricosus"
binomial = "Placostylus bivaricosus"
species_authority = Gaskoin, 1854

The Lord Howe Flax Snail or the Lord Howe Placostylus, "Placostylus bivaricosus", is a large terrestrial snail found only on Lord Howe Island off the east coast of Australia. Its status has declined from common to endangered since rats were accidentally introduced to the World Heritage island in 1918.

Description

The genus "Placostylus" is a group of large ground dwelling gastropods with a disjunct distribution in the South west Pacific from the Solomon Islands, Fiji, and New Caledonia, to Lord Howe Island and the northern extremity of New Zealand. The Lord Howe Flax Snail has a brown, pointed shell up to 7 cm long and 2 cm in diameter.

Conservation

pecies decline

Historical accounts and fossil evidence indicate that the Lord Howe Island Flax Snail was formerly widespread and abundant on the island. The decline was first noted in the 1940s and the species is now listed as critically endangered.

The Black Rat is considered to be the major predator of this species and likely to be a significant threat to its survival. European Blackbirds and Song Thrushes (self-introduced around 1950) are also thought to be predators of the snail.

Habitat clearing and modification and habitat disturbance, possibly herbicides and pesticides also add to the species decline.

Recovery

In 2001, a recovery plan was completed to protect and recover the Lord Howe Island Flax Snail in the wild. Actions include habitat and population surveys, community awareness raising and a captive breeding program.

The Lord Howe Island Board, responsible for implementation of the recovery plan, has since constructed a rodent and bird proof enclosure for the project and the first generation of captive bred Lord How Island land snails has hatched.

Over a period of two years, school children will closely monitor the captive snail population their eggs and then measure growth rates and survival rates of the juvenile snails.

Rodent control or eradication on the island is crucial for the long-term survival of the snail in the wild.

References

* [http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=66769 Threatened Species Profile Lord Howe Island Land Snail (Australian Government, Department of Environment and Water Resources)]

External links

* [http://www.fnpw.org.au/enews044/LHISnails.htm Placostylus Captive Breeding (Foundation for National Parks & Wildlife]
* [http://www.fnpw.org.au/enews3/lhiPhasmid.htm Rodent eradication on Lord Howe Island (Foundation for National Parks & Wildlife)]