No.18 2008

Science Centres: Coasts

Modelling the early life of Antarctic toothfish

Huge undersea landslide discovered in Cook Strait

New methane-munching bacteria discovered

More vast underwater canyons revealed

Wellington hosts international deepsea coral symposium

New methane-munching bacteria discovered Methane plumes(vertical shapes) at the undersea Wairarapa methane seep. An unusual group of methanotrophs – bacteria which digest methane – has been identified by NIWA scientists investigating the fate of undersea methane seeps in the Cook Strait-Wairarapa region. The bacteria were collected in water samples from the methane seep plumes, at a depth of around 1000 m.
Wellington hosts international deepsea coral symposium Deepsea coral scientists from around the world will gather in Wellington later this year to attend the Fourth International Deepsea Coral Symposium. The event, hosted by NIWA, runs from December 1–5 2008.
Huge undersea landslide discovered in Cook Strait Scars, indicating large-scale slope failures, are clearly visible at a depth of around 140 m in Cook Strait. Undersea mapping in Cook Strait has revealed detail of massive rock movements around a huge canyon, Nicholson Canyon, less than 15 km from Wellington Airport. Using state-of-the-art multibeam equipment, scientists have discovered that the canyon walls are very steep. The over-300 m high walls have clearly visible scars indicating a large-scale slope collapse or landslide.
Modelling the early life of Antarctic toothfish Top: Modelled representation of where Antarctic toothfish spawn. Bottom: The predicted distribution of eggs and larvae after two years, as they drift with ocean currents away from the spawning grounds. Antarctic toothfish are found exclusively in waters between 600 S and the Antarctic continent.
More vast underwater canyons revealed Bathymetry (water depth) map of the Moeraki, Haast, Waiatoto, Arawata, and Cascade Canyons off South Westland. NIWA geologists have mapped more vast underwater canyons off South Westland, including the biggest yet. Multibeam sonar mapping of the Hokitika and Cook Canyons from RV Tangaroa in 2005 revealed complex, meandering rivers and deep ravines which dwarf any features seen on land in New Zealand.