New Zealand screw shell (Maoricolpus roseus)
What to look for
- Smooth conical shell.
- Generally brown, fading to purple/white with age.
- Broader tapering shell with up to 18 whorls.
- Grows to 9 cm long, usually ~6 cm long.
- Lying on or partially buried in sand, mud or gravel.
- Also found in crevices.
- Low intertidal & subtidal up to 130m depth.
- Densely blankets the sea floor with live & dead shells.
- Can compete with scallops & commercially farmed shellfish for food.
- South east to north-east coast Tasmania
- Bass Strait
- Wilson's Promontory Victoria & north to Botany Bay NSW
What you can do
- Inspect & clean niche areas & antifoul your vessels regularly.
- Clean & dry equipment before transporting & using in a different location.
More information on this pest can be found on the National Introduced Marine Pest Information System.