How to tag southern bluefin tuna

Commercial fishers must tag southern bluefin tuna whenever they’re caught or landed. Find out how to tag southern bluefin tuna and why it's important.

What does "tagging" fish involve?

A tag with an official New Zealand code is attached to fish that are caught. Southern bluefin tuna are the only species that New Zealand fishers need to tag. This is a legal requirement.

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

Fisheries (Southern Bluefin Tuna Catch Documentation Scheme) Regulations 2017

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 are easy to read.


These instructions are for attaching tags to fish that will be frozen. If you're tagging fish that won't be frozen, you might need to change how you attach the tag. This is because they get processed differently.

this image applies to step 1

1. Tie the band of the tag to the bottom of the gills (the throat) of the tuna. Insert the end of the band into the slot at the base of the tag. Make sure to keep the jagged (rough) surface of the tag 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. This will help to protect the tag with the gill covers. This can help keep the tag from breaking if it gets damaged.


this image applies to step 3

3. After fastening the band, slide the tag around so that it's on the inside of the body.

Who is responsible for tagging?

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

However, a licensed fish receiver (LFR) will need to do it if they receive a fish without a tag.

LFRs also have other responsibilities.

Find out what else LFRs have to do

Make sure you have up-to-date tags

We'll give you new tags each year. Tags are a different colour each year. Check that you have the most recent one. All tag numbers start with the current year. For example: the code for 2021 is (NZ21 00001)

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

Why tagging is important

Attaching tags to caught fish helps organisations that manage fisheries internationally to:

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

The Commission for the Conservation of Southern Bluefin Tuna (CCSBT) manages southern bluefin tuna fishing. 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.

Learn more about international fisheries reporting

Who to contact

If you have questions about tagging southern bluefin tuna, email

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