Lobster: Tag and release


If you are a diver or a pot fisherman then your summer lobster catch may have more going for it than just a delicious meal. Your lobster could be carrying a tag and the information on that tag can be used to ensure the sustainability

of lobster stocks and a quality fishing experience for all legitimate users.

The Rock Lobster Industry Council is a contracted research services provider to the Minister of Fisheries and operates an extensive rock lobster stock monitoring and research project which includes a lobster tag, release and recapture programme.

The object of this scheme is to estimate growth, determine distribution and seasonal patterns in the abundance and size of rock lobsters, and to determine movement patterns within rock lobster management areas.

Rock lobsters increase in size each time they moult.

Smaller lobsters can moult several times in one season, while older, larger lobsters moult less frequently. Mature female lobsters grow more slowly than male lobsters because they expend a great deal of energy on egg-bearing.

TAGGING AND RELEASING


When a lobster is tagged, the sex, stage of female maturity, length, carapace, tail width, and the number of injuries are

recorded.

Five per cent are double tagged to give an indication of possible tag loss. The tags are inserted on the top side into the tissue between the carapace and tail.

This enables the tag to stay in place even when the lobster moults, and also enables the tag to be clearly visible.

At the point of release, the latitude, longitude and water depth are recorded.

Every attempt is made to release the lobster as close as possible to where it was caught.

RECAPTURE

Recapture of tagged lobsters provides information on growth and movement.

Recreational lobster fishers can pass on that information on amateur tag recapture cards.


These are available from the Rock Lobster Industry Council. Contact it on (04) 385 4005 or lobster@seafood.co.nz.

The details of the recapture which are useful include the sex, tail width, number of injuries, the tag number and prefix, and the depth, location and whether or not the tagged lobster was retained or released.

The number of injuries means the number of missing legs and antennae, or severe damage such as horns missing or

holes in the carapace. The prefix of the tag number is important as there are tagging programmes in different places and tag numbers may be duplicated. Although many tagged lobsters are reported by fishermen, some escape detection and are noticed only when the catch is cooked. The prefix in these cases identifies the source of the tag.

If a legal-sized tagged lobster is recaptured, it may be landed in the usual way.

You may choose to re-release the legal lobster, as the additional information when it is caught again will be very useful.

If the lobster is under minimum legal size or carrying eggs it must be returned to the water in any case. When a tagged

lobster is re-released, please record the position and depth.

As with any tagging programme, there will be a small percentage of recaptures so there will not be screeds of paperwork to complete.


When you do get a recapture though, please fill in the card and return it to us. If you are going to retain the recaptured

lobster, remove the tag gently and attach to the completed form. You need a new form for each recapture.

Tagging details are an essential component of rock lobster stock assessments, providing valuable information on growth rates.

Since the 1993/94 fishing year, there has been a concerted effort by the rock lobster fishing industry to supplement

historical tagging data with extensive and representative tagging.

Their commitment has seen 157,000 lobsters tagged and more than 23,000 recaptures, including multiple re-releases

of tagged lobsters being reported.

This programme is industry led by the Rock Lobster Industry Council, and supported by scientists from Niwa, Breen

Consulting and Starrfish Consulting.

Industry technicians work with commercial fishermen who volunteer their time and boats for this important research.

- Hamilton News

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