Bluefin tuna being returned to the sea after being tagged. (Photo: NOAA)

Pacific tuna tagging project advances

NEW CALEDONIA
Wednesday, March 17, 2010, 00:00 (GMT + 9)

The world’s largest-ever tuna tagging project has released over 250,000 tagged tuna into the equatorial Western and Central Pacific Ocean; 35,000 tags have already been recovered.

The data collected will help sustain and protect the world’s largest tuna resource, stated twenty scientists gathered recently at an International Tuna Tagging Workshop at the Secretariat of the Pacific Community’s (SPC) headquarters.

In August 2006, the joint SPC/PNG National Fisheries Pacific Tuna Tagging Programme began in Papua New Guinean waters, where 15 per cent of the world’s tuna is fished. In 2007, the New Zealand government invested NZD 5 million (USD 3.5 million) and the European Union (EU) EUR 1.56 million, which allowed the project to cover the whole equatorial Western and Central Pacific Ocean.

The last tagging cruise ended in October 2009. For around 90 days at a time, a 30-strong team of experienced Solomon Islands fishers and SPC biologists navigated the ocean on a pole-and-line fishing vessel, easing the fish on board to measure, tag and return them to sea within 15 seconds.

Most tags are thin rods inserted under the tuna’s dorsal fin. Bigger fish, though, were given express surgery and sent back to swim with an archival tag.

Tags carry only a serial number, but the hi-tech archival tags keep track of geographical movement. They measure light throughout the fish’s journey and is then interpreted based on sunrise and sunset schedules per time zone.

A vast communications operation was arranged to inform fishers, tuna canneries and fishery agencies across the globe about the project and a reward offered for every tag sent back to SPC.

The results of the tagging project will provide information on various biological and fishery processes such as exploitation rates, mortality, movement, growth rates and spatial and temporal variability.

The SPC team met earlier this month with representatives from the Indian Ocean Tuna Commission (IOTC), the Inter American Tropical Tuna Commission (IATTC) and PNG National Fisheries.

They were joined by independent leaders in the field of data analysis from the US’s University of Hawaii, National Oceanic and Atmospheric Administration (NOAA) and National Marine Fisheries Service (NMFS) and New Zealand’s National Institute of Water & Atmospheric Research (NIWA) for an analysis workshop.

A work plan for the months ahead will be created by these groups to transform the statistics into useful information for fisheries.

“The growth of the tuna industry in the Pacific over the last decade has occurred in parallel with the growing use of fish aggregating devices (FADs). It is really exciting that we now have data that can measure the impact of these FADs on the quantity and quality of tuna in the region,” said Brian Kumasi of PNG National Fisheries.

“This information, in addition to the other analyses that are planned, will lead to better management of our shared fishery resource,” he added.

Related article:

- Deepening albacore tuna knowledge

By Natalia Real
[email protected]
www.fis.com

 National Oceanic and Atmospheric Administration NOAA/NMFS

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