How to tag southern bluefin tuna

Commercial fishers must tag southern bluefin tuna whenever they’re caught or landed. Find out how to tag fish and learn about the related catch documentation scheme.

The importance of tagging

Attaching tags to caught fish helps international fisheries management organisations to:

  • reduce illegal fishing activity
  • monitor and record fishing activity
  • perform cross-checks on reported catch, import, and export information.

Tagging southern bluefin tuna

Southern bluefin tuna are the only species that fishers (or licensed fish receivers) need to tag in New Zealand fisheries.

  • Fishers must tag each southern bluefin tuna they catch.
  • Licensed fish receivers must tag any southern bluefin tuna that are landed without a tag.

Overseas markets will not accept imports of southern bluefin tuna without a tag and proper documentation.

How to tag southern bluefin tuna

Make sure that you attach the tag so that:

  • it will stay fastened to the fish
  • the tag number and other information can be easily read.

We will give you new tags each year. Tags are a different colour each year – so check you have the latest one. All tag numbers start with the current year, for example: (NZ17 00001) for 2017.

If you intend to fish for southern bluefin tuna and haven’t received the latest year’s tags, you can contact us to request them.


These instructions are for attaching tags to fish that will be frozen. When tagging fish that won't be frozen – because the fish are processed differently – you might need to change how you attach the tag.


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1. Tie the band of the tag to the bottom of the gills (the throat) of the tuna and insert the end of the band into the slot at the base of the tag. Make sure to keep the jagged (rough) surface on the inside.



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2. Pull and fasten the band. We recommend you attach the tag to the front end (nearest to the head) as much as possible, to protect the tag with the gill covers. This may prevent the tag breaking in case of damage.



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3. After fastening the band, slide the tag around so that the plate is on the inside of the body.





Who is responsible for tagging the fish?

In most cases, a fisher (with a permit) will tag the fish.

However, if they don’t have a tag, then a licensed fish receiver (LFR) will need to do it. LFRs also have other responsibilities.

Background on tagging tuna

The Commission for the Conservation of Southern Bluefin Tuna (CCSBT) is responsible for the sustainable use of southern bluefin tuna. In 2009, the Commission started using a Catch Documentation Scheme (CDS).  Part of the CDS is tagging all southern bluefin tuna caught by CCSBT member countries.

What is the catch documentation scheme?

Catch documentation schemes involve checking commercial fishing catches at (or before) the point where the vessel lands. This makes it harder for illegally caught fish to be traded internationally. The process involves checking:

  • the origin of the caught fish
  • the weight of the caught fish
  • the species of the caught fish
  • shipments of the fish or its products
  • whether the fish was caught legally.

Who to contact

If you have any questions about the information on this page, email 

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