A major New Zealand research expedition to the Ross Sea will shed new light on the area's unique ecosystem and deepen understanding of the Antarctic toothfish, Niwa scientist Dr Matt Pinkerton said.
Dr Pinkerton, of Wellington, an ecosystem modeller who is studying Antarctic toothfish ecology, discussed aspects of the expedition and toothfish research yesterday during the 2008 Annual Antarctic Conference at the University of Otago.
More than 80 people attended his presentation, which focused on the 50-day New Zealand International Polar Year (IPY)-Census of Antarctic Marine Life (CAML) Voyage to the Ross Sea, undertaken aboard the research vessel Tangaroa in February-March this year.
It would take several years to analyse all of the data gained from the research voyage, but it would provide a much fuller picture of the ecological context of the Antarctic toothfish, Dr Pinkerton said.
Twenty-six scientists and 18 crew took part in the voyage, during which 88 fish, eight squid and 18 octopus species were recovered and identified.
Dr Pinkerton noted that in 1997 a New Zealand fishing vessel had started what were now international fishing operations focusing on the Antarctic toothfish, which were found in the Ross Sea area.
Fishing now removed about 3000 tonnes of the fish each year.
A second toothfish species, Patagonian, was found elsewhere, in subantarctic waters, he said.
Fishing for the Antarctic toothfish was well controlled by a single Australian-based regulatory authority, the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR).
There was considerable debate about whether allowed fishing levels were too high or two low, and further scientific research was needed to guide the discussion, he said.
The Antarctic toothfish, which can grow to about 2m in length, featured in the Antarctic food web as prey for Orca, and for Weddell seals.
Dr Pinkerton said the toothfish also played a significant role as the top fish predator, in regulating other fish species which served as its prey.
The three-day conference ended yesterday afternoon.