22 Aug 2014

The habits of NZ's Great White Sharks

From Nine To Noon, 9:36 am on 22 August 2014

In 1995 marine scientists from NIWA and the Department of Conservation tagged 95 great white sharks in the waters around Stewart Island and the Chathams.

Stewart Island W Lyon with canvas
NIWA scientist Malcolm Francis tagging white shark with acoustic tag. Photo: Warrick Lyon/NIWA.

Since then they've tracked their migration patterns, how far they travelled and why. They found most migrate to the tropics during the winter months - travelling about 100 kilometres a day.

Gallery: Great White Sharks

SPOT tracks
Tracks of three SPOT-tagged white sharks tagged at Stewart Island. Coloured dots are average daily positions (long gaps between dots indicate one or more days without satellite fixes). Blue line = 1,000 m depth contour. NIWA/DOC.

The researchers, Dr Malcolm Francis of NIWA, and Clinton Duffy of DOC, also found the sharks migrate in a straight line, but haven't yet worked out why.

Dr Malcolm Francis explains the findings to Lynn Freeman on Nine to Noon.