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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: Sea Squirt (Clavelina)

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Clavelina oblonga and Clavelina lepadiformis are two types of sea squirt, or ascidian, that have recently established in New Zealand waters. Clavelina oblonga is only known at Aotea Great Barrier Island. We need your help to track their spread so we can learn more about their impact.

How to identify this species

  • Gelatinous to touch
  • Forms colonies
  • Individuals 2-5 cm long
  • Tubes have white, yellow or pink bands around siphons

Photos supplied by: Auckland Council and Northland Regional Council

Clavelina oblonga

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

Aotea / Great Barrier Island (Port Fitzroy, Smokehouse Bay)


 

Clavelina lepadiformis

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

Whangārei Harbour, Whangaparāoa, Waitematā Harbour, Tauranga Harbour, Napier, Wellington Harbour, Porirua Harbour, Picton Harbour, Nelson Harbour, Lyttelton Harbour, Otago Harbour

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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