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  1. Mulberry2_amber-louise_burberry Raised purple bumps on shell by AL Burberry
  2. Main_image_mulberry_c_gillies-cropped Purple bumps on white shell by C Gillies

Mulberry Whelk

Tenguella marginalba


  • Mulberry whelks are a small to medium sized marine snails (mollusc)
  • They have distinctive raised bumps of dark purple or black on a grey or whitish background giving them a checked, berry appearance of a ‘Mulberry’.
  • They have a low spire and tend to be longer then they are high.
  • Size:  up to 25 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

Mulberry whelks, 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 mid to low tide levels. Usually found in rock pools and crevices, particularly in areas where oysters, barnacles and Galeolaria caespitosa (Sydney rock coral) worms are found.
  • Merimbula NSW up to Central QLD.


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.



  1. Search Species

  1. What Else?

    Mulberry welks could be confused with several Austrocochlea species (A. porcata, A. concamerata) or Thais ambustulatus, all of which can have similar chequered appearance. Both A. porcata and A. concamerata lack raised nodules or bumps and are generally as wide as they are long. T. ambustulatus is related to the mulberry welk but is normally found sub-tidally. The mulberry welk has dark brown or black markings on the inside lip which T. ambustulatus does not have. 

  1. Did You Know?

    Mulberry whelks are carnivores and eat oysters, barnacles, worms and other molluscs. They use their specialist tongue (called a radula) to bore a small hole in the shell or tube of their prey, releasing a strong enzyme which creates a “mollusc milkshake” which they then drink. This process can take up to 48 hours.

    Can also be found in estuaries.