A combined Department of Conservation (DOC), National Institute of Water & Atmospheric Research (NIWA) and Auckland University research team has returned to Stewart Island / Rakiura this week in an attempt to learn more about an often much maligned creature, the white shark, also known as the great white or white pointer.
The research will be conducted from the DOC vessel Hananui from 22 March - 6 April 2011, around the Titi Islands located off Stewart Island's northeast coast and Ruapuke Island in Foveaux Strait as weather permits.
Boat divers and kayakers are advised to avoid the areas where the research is being conducted while the boat is on station and for at least 24 hours afterward as the team will be using berley (a mixture of minced fish and fish oil) to attract sharks.
“Fragments of berley may settle to the bottom and continue to hold a shark or sharks at the site for several hours after berleying has ceased,” says DOC shark expert Clinton Duffy.
The principal study sites for this trip will be Bench, Edwards and Ruapuke Islands. The research team will shift between these islands and other sites depending on weather conditions and the presence or absence of sharks.
“We will relay the location of the study vessel daily via local fishermen’s radio, to alert any divers or kayakers,” says Mr Duffy. “This information will be updated each time the vessel shifts site.”
The waters around Stewart Island have long been recognised as a hot spot for white sharks in New Zealand. This is the fifth year the team has travelled south to undertake photo-identification and tagging in an attempt to learn more about this now protected species.
“Any tags deployed will be set to ‘pop off’ and float to the surface after a pre-determined time , usually around 6 – 12 months,” says Mr Duffy.
“The data transmitted from the shark will tell where it has travelled since tagging took place and, if the tag can be retrieved, will also provide a wealth of other information such as dive times, depths and water temperatures.”
Last year a total of 28 individual sharks were photo-identified around Bench, Edwards and Ruapuke Islands, including five sharks that had been previously sighted in 2009 and two that the team has seen every year since 2008. Since the team began its research around Stewart Island in 2007, they have identified 48 individual sharks.
White sharks became a fully protected species under the Wildlife Act from 1 April 2007. It is therefore illegal to hunt, kill or harm a white shark within New Zealand’s Exclusive Economic Zone. It is also illegal in New Zealand to possess or trade in any part of a white shark.