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Marine Pest of the Week
Marine Pest of the Week is a series in which you can learn about the marine pests threatening New Zealand’s waters, how to identify them, and what you can do to help protect our marine environment.
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Marine Pest of the Week – Eudistoma Australian Droplet Tunicate

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As the weather gets warmer we’ll see more of this unsightly pest around parts of Northland and Auckland. Let’s see how to ID it and when to report it.

With a slimy snot-like appearance this species can form big colonies on rocks, aquaculture equipment and marine structures. In its a free-swimming larval stage it can spread far and wide. It dies-back over winter but in summer it leaves no space for native species and changes the appearance of our beautiful coastal places.


Eudistoma // Photo credit: Sam Happy

This species is known to be in the following locations in Northland and Auckland. If you find it outside this area, please report it.

Parengarenga Harbour, Rangaunu Harbour, Mangonui Harbour, Whangape Harbour, Whangārei Harbour, Whangateau Harbour, Sandspit, Kawau Island, Mahurangi Harbour, Waitematā Harbour, wider Hauraki Gulf.

This list is correct to the best of our knowledge at the time of publishing – for a full list of marine pest locations, please go to the Marine Biosecurity Porthole.

From the team at Clean Below? Good to Go – visit marinepests.nz to get everything you need to know about marine pests ID, boats, rules and more.


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