Movements and possible stock relationships of the New Zealand barracouta, Thrysites atun, from tag returns

Abstract

BetweenMarch 1984 and January 1987, 4097 barracouta were tagged to determine movements and possible stock relationships. Forty‐two recaptures have been recorded, with a greatest minimum distance travelled of 500 nautical miles and maximum time at liberty of 398 days. Most fish were tagged on the east coast of the South Island, New Zealand, and were recaptured along the east coasts of the North and South Islands. These movements appear to coincide with seasonal spawning migrations. It was not possible to determine stock relationships from this study alone but, in combination with the results of other research and commercial data, the existence of at least 3 separate spawing stocks is suggested: east coast North and South Islands; west coast South Island; and Chatham Islands. The relationship of west coast North Island and southern South Island barracouta to these suggested stocks is unclear.

Key words:

• Thyrsites atun
• tagging
• migration
• stocks