- Noddiwinks are small marine snails (molluscs)
- They are light blue to grey in colour and have bumps or nodules around the twist (whorl) of their shell which spirals up to a light brown to reddish-brown sharp tip (apex).
- Size: Up to 18 mm
What to Observe
Search area for 30 minutes and record under the following categories:
- Abundant - found easily with little searching
- Frequent - found with minimal searching
- Rare - only 1 or 2 individuals found with intensive searching
- Not found - not present during search
ClimateWatch Science Advisor
Noddiwinks, like all marine snails (molluscs), are under increasing stress due to ocean acidification which can weaken their calcium carbonate shells and reduce body condition. This makes them more prone to disease, predation and low reproduction. Increasing water temperature as a result of climate change will likely affect their abundance and cause a southward shift in their distribution.
When To Look
Throughout the year.
Where To Look
- Common on rocky shores, from high tide level to wave splash zone. Usually found very high up the platform in heavily weathered sandstone areas, where there is little to no standing water.
- Fremantle WA, NT, QLD down to Southern NSW
Davey, K. (1998). A Photographic Guide to Seashore Life of Australia. New Holland Publishers Australia Pty Ltd.
Edger, GJ. (2008). Australian Marine Life. The Plants and Animals of Temperate Waters [2nd Ed]. New Holland Publishers Australia Pty Ltd.
Noddiwinks are able to live high up on the shore, a feature which separates them from most other marine snails. Blue periwinkles (Austrolittorina unifasciata, Austrolittorina (Afrolittorina) praetermissa) also live high up on the shore but they can be separated from noddiwinks by their smooth shelled and slightly smaller in size. Noddiwinks have easily seen nodules or bumps on their shells.
Did You Know?
They can also be found on Lord Howe Island and Norfolk Island.
Noddiwinks are herbivores and scrape algae and lichens from the rock with a specialised rasping tongue called a radula.