Lord Howe Placostylus - profile

Indicative distribution

Loading map...

Key:

known

predicted

The areas shown in pink and/purple are the sub-regions where the species or community is known or predicted to occur. They may not occur thoughout the sub-region but may be restricted to certain areas. ( click here to see geographic restrictions). The information presented in this map is only indicative and may contain errors and omissions.

Scientific name: Placostylus bivaricosus

Conservation status in NSW: Endangered

Commonwealth status: Endangered

Gazetted date: 04 Apr 1997

Profile last updated: 21 Jan 2020

Description

A large ground-dwelling land snail with a pointed shell up to 8 cm in length, medium to dark brown in colour (weathering to white in older animals) and with a thickened lip in mature animals. The body is black. There are three different subspecies: one presumed extinct, one possibly extinct and the other with a declining distribution.

Distribution

Found only on Lord Howe Island. Formerly widespread on Lord Howe Island but now restricted to the mid-Island lowlands and the area around North Bay. Populations may also survive on isolated slopes at southern end of the Island.

Habitat and ecology

Found in leaf litter in rainforest areas.
Most recent records have been from Greybark/Blackbutt and Kentia Palm lowland forest on calcarenite soil, often but not always in the vicinity of Banyan Figs.

Regional distribution and habitat

Click on a region below to view detailed distribution, habitat and vegetation information.

Threats

Small population leading to loss of genetic diversity.
Loss of habitat through clearing of lowland forest.
Use of herbicides and pesticides in areas of habitat.
Invasion of habitat by introduced weeds.
Predation and habitat disturbance by free-ranging domestic poultry.
Trampling and habitat disturbance by domestic stock.
Climate change.
Potential for introduction of non-native invertebrates (eg Fire/Crazy Ant).
Secondary poisoning from brodifacoum used in the rodent eradication.
Sub-surface irrigation with treated effluent.
Predation by introduced predators, particularly the Black Rat.
Habitat loss and fragmentation due to disturbance via roads, development / building activity.
Predate juveniles; high densities of blackbirds in the area of occupance of the snail.

Recovery strategies

A targeted strategy for managing this species has been developed under the Saving Our Species program; click here for details. For more information on the Saving Our Species program click here

Activities to assist this species

Establish and maintain a captive breeding program for the species on Lord Howe Island.
Control introduced predators.
Take strict precautions during the use of herbicides and snail baits, and consider alternatives where available.
Exclude domestic stock and domestic poultry from areas of habitat.
Assist with the control of introduced weeds in areas of habitat.
Prevent ornamental plants and weeds from escaping into native forest areas.
Protect lowland forest habitat from clearing or disturbance.
Regenerate area of potential habitat on Blackburn Island for possible future use as a rodent-free translocation release site.
Regenerate areas to re-establish links between habitat remnants.
Monitor status of known populations.
Implement and monitor the quarantine plan.
Investigate the impact of the introduced Blackbird and Song Thrush on the Lord Howe Placostylus.
Research into ecology and genetics of species to provide information to assist in its conservation.
Survey areas of high potential habitat in Southern Mountains area of Lord Howe Island to identify any extant populations.

Information sources

Department of Environment and Climate Change (NSW) (2007) Lord Howe Island Biodiversity Management Plan. Department of Environment and Climate Change (NSW), Sydney.
Murphy, M.J. and Nally, S. (2004) Case studies in implementing the NSW Threatened Species Conservation Act 1995 for invertebrate conservation. Australian Zoologist.
NSW National Parks and Wildlife Service (2001) Lord Howe Placostylus Placostylus bivaricosus (Gaskoin, 1855) Recovery Plan. NSW NPWS, Hurstville NSW.
NSW Scientific Committee (1997) Placostylus bivaricosus (a large land snail) - Endangered species determination - final. DEC (NSW), Sydney.

IBRA Bioregion	IBRA Subregion	Known or predicted	Geographic restrictions region

Ocean	South Pacific Ocean	Known	None
Pacific Subtropical Islands	Lord Howe Island	Known	None

Nature conservation

Threatened species