Fauna Spotters logo

Stoddart's Keeled Glass-snail (Advena stoddartii)

This is a terrestrial land snail endemic to the Norfolk Island Group. It is associated with ground cover such as leaf litter and fallen palm fronds, which may be affected by clearing or other ground-disturbing works.

Conservation status

Commonwealth, EPBC Act 1999: Critically endangered.

Seasonal planning

Advena stoddartii breeds year-round in the Norfolk Island Group, with reported breeding peaks from December to March and January to June.

Seasonal evidence: From published sources for this species.

Timing varies between sites and years.

  • Breeding season: Advena stoddartii breeds year-round in the Norfolk Island Group, with reported breeding peaks from December to March and January to June.

Identification: Appearance

Its shell is imperforate and depressed-conical, measuring at least 14 mm across and 8 mm high.

Its shell is imperforate and depressed-conical, measuring at least 14 mm across and 8 mm high.

Identification: Confirming identity

Confirm the identity of any suspected record with a specialist and a photograph or voucher, as required by the relevant permit.

Distribution: Known range

Early records and subfossil material suggest the species occurred on Norfolk, Nepean and Phillip islands. It was last collected at Ball Bay and Duncombe Bay in 1945; a privately held specimen reportedly collected on Phillip Island in the 1990s suggests it may have survived there.

Early records and subfossil material suggest the species occurred on Norfolk, Nepean and Phillip islands. It was last collected at Ball Bay and Duncombe Bay in 1945; a privately held specimen reportedly collected on Phillip Island in the 1990s suggests it may have survived there.

Distribution: National mapping

The Commonwealth species distribution model (SNES) maps where the species or its habitat is known, likely or may occur. Use it with local records and site inspection.

Habitat: Habitat

The species is associated with sheltered ground-level sites, including beneath leaf litter, logs and rocks. Fallen palm fronds are noted as a particularly common place to find it.

The species is associated with sheltered ground-level sites, including beneath leaf litter, logs and rocks. Fallen palm fronds are noted as a particularly common place to find it.

Foraging habitat: Diet

Not documented in the published sources used for this profile.

Not documented in the published sources used for this profile.

Breeding habitat: Breeding

The species is live-bearing.

The species is live-bearing.

Sheltering habitat: Shelter

It shelters beneath leaf litter, logs and rocks, particularly fallen palm fronds.

It shelters beneath leaf litter, logs and rocks, particularly fallen palm fronds.

Threats: Threats

Habitat degradation and modification, invasive weeds, land clearing and stock grazing are identified as contributors to decline. Predation by rodents and feral chickens, as well as drying conditions and reduced soil moisture, are also potential pressures.

Habitat degradation and modification, invasive weeds, land clearing and stock grazing are identified as contributors to decline. Predation by rodents and feral chickens, as well as drying conditions and reduced soil moisture, are also potential pressures.

Threats: Works risk

Land clearing and other works that remove or disturb ground cover could affect the sheltered sites it uses beneath leaf litter, logs, rocks and fallen palm fronds. Habitat modification may also compound pressures associated with invasive weeds and introduced animals.

Survey methodology: 1. Species-specific methods

Use methods consistent with the Commonwealth survey guidelines and engage a specialist with the right permits.

Recent surveys have failed to locate the species, including a targeted survey on Phillip Island.

Survey methodology: 2. Commonwealth guidance

For EPBC Act referrals, survey effort and methods should be consistent with the on-ground surveys and data for referred actions under the EPBC Act, read with the Significant impact guidelines 1.1.

Survey methodology: 3. Limits

A non-detection is not proof of absence. Match survey timing to the species and season, and record effort.

Vegetation associations

Source-checked associations and automatically indexed candidates are separated below. An association does not establish site presence, preference or dependence.

No species-specific vegetation association has been indexed or source-checked in this evidence library. This is an evidence gap, not evidence of no association.

Ecosystem associations

Source-checked associations and automatically indexed candidates are separated below. An association does not establish site presence, preference or dependence.

No species-specific ecosystem association has been indexed or source-checked in this evidence library. This is an evidence gap, not evidence of no association.

Soil and substrate associations

Source-checked associations and automatically indexed candidates are separated below. An association does not establish site presence, preference or dependence.

No species-specific soil association has been indexed or source-checked in this evidence library. This is an evidence gap, not evidence of no association.

Water and wetland associations

Source-checked associations and automatically indexed candidates are separated below. An association does not establish site presence, preference or dependence.

No species-specific water association has been indexed or source-checked in this evidence library. This is an evidence gap, not evidence of no association.

Fauna records and mapped habitat: Not yet analysed

Record locations can be overlaid with mapping, but record frequency alone does not measure habitat preference. No species is excluded from desktop assessments by this analysis.

No quality-controlled record-to-map analysis has been completed for this species. The existing generalised distribution dots and indicative range polygons have not been treated as precise occurrence coordinates.

A defensible run needs dated, independently attributable records, coordinate uncertainty, duplicate and captive-record checks, layer versions and regional scope. Preference and absence require additional survey-effort and detection evidence.

Habitat limitations and contrary evidence: No supported exclusion recorded

Not recorded is not the same as cannot occur. Low suitability, resident habitat, breeding habitat and occasional movement are different conclusions.

This library has not established a vegetation, ecosystem or soil-type exclusion for this species. This does not mean all habitat is suitable; the evidence needed to justify an exclusion has not been assembled.

Habitat limitations and contrary evidence: Before using a negative association

  • Confirm the taxon, geographic region, life stage and habitat function covered by the evidence.
  • Check survey methods, season, repeated effort and detectability before interpreting non-detection.
  • Investigate credible contradictory records and microhabitats absent from broad mapping.
  • Do not convert a missing map class, low record count or failed data request into species absence.

Before disturbance: 1. Desktop and approvals

Confirm whether the project could affect the species before works begin.

Check national mapping, state records and recent surveys for the site. An action likely to have a significant impact on this nationally listed species needs EPBC Act referral, and state permits apply where it is state listed.

Before disturbance: 2. Plan to avoid

Design the footprint, timing and access to avoid known or likely habitat, and brief crews on what to look for and who to call.

During disturbance: 1. Controls

Keep works inside the approved footprint and conditions.

Fence or mark habitat to be retained and keep machinery, stockpiles and spoil out of it.

During disturbance: 2. Stop and report

If the species is found unexpectedly, stop work at that spot and contact the project ecologist and the relevant agency.

After disturbance: 1. Records

Record outcomes.

Record sightings, habitat lost or retained and any injury or death, and report them under the approval conditions.

Rehabilitation: 1. Restore

Restore disturbed habitat where possible.

Reinstate disturbed ground with local species, return logs, rocks and litter, and control weeds and erosion until the site is stable.

Sources