A system for tagging great white sharks that can be achieved with the fish still in the water has been introduced by Australian researchers.

Keeping a track on the movements of great white sharks has provided valuable information for divers, surfers and research scientists. Boffins invent shark tagging device 13oct03 THE ticklish business of tagging great white sharks for research has been made a little easier with a new invention by scientists at the CSIRO. Their tagging poles allow the rare sharks to be tagged in the water next to the vessel. New tagging method for white sharks Six white sharks have been tagged by scientists using new specially developed tagging poles allowing them to be tagged in the water next to the vessel. "The sharks ranged from two metres to more than four metres," says project leader John Stevens of CSIRO, who is now waiting to receive signals from the electronic tags. The sharks were tagged off the southern coast of Western Australia, after reports of a recent stranding of sperm whales. "We receive reports of white sharks from several locations in Western Australia, but the trick is to be in the right place and at the right time," says CSIRO's Barry Bruce. "It's sad to see the death of a whale pod, but sharks play an important role in returning the energy and nutrients from the carcases back to the marine ecosystem and are naturally attracted to such an event. "In this case, the whale stranding provided an ideal opportunity to get close enough to tag white sharks." The sharks were tagged with either electronic tracking tags, or standard identification tags, says Dr Stevens. "Getting a tag onto a thousand kilkogram shark is quite a task," says Dr Stevens, "even though technology to track animals by satellite has been around for more than a decade. "And there are many things that have to go right even after tags are placed on sharks." Two pop-off archival (PAT) tags and two satellite-tracking tags were attached to sharks. "The tag has to stay on, delicate electronics need to survive the rigors of being on a shark during its daily activities and the sharks need to surface so that the tags can transmit signals," says Dr Stevens. PAT tags store information on shark movement and behaviour for several months before releasing from the shark, floating to the surface and transmitting their information via satellite. The satellite-tracking tag allows the shark's progress to be plotted whenever it surfaces and successfully transmits a signal via the ARGOS satellite system. The shark tagging team - assisted by staff from the Aquarium of Western Australia (AQWA) and local cinematographers David Riggs and Jennene Paris - spent three days east of Bremer Bay, the site of a recent stranding of sperm whales. They were aboard Quadrant, a commercial fishing vessel skippered by Geoff Campbell. The tagging was funded by the AQWA Research Foundation, as part of a project on white shark movement patterns off southern Australia. The CSIRO team achieved a world first two years ago when tracking tags were successfully attached to two small white sharks off eastern Australia and traced for up to four months. A three-metre female white shark recently PAT-tagged by the team was estimated to have travelled at least 1300 kilometres along the southern coast of WA between May and June. This was the team's third attempt to locate and tag white sharks in WA. The tagging trip was carried out under permits from the WA Department of Conservation and Land Management and WA Fisheries. Great White sharks under attack by curio pirates October 16, 2003 By Melanie Gosling Conservation officials have been tipped off that perlemoen poachers, faced with declining stocks of the lucrative shellfish, are killing protected Great White sharks and selling jaws and teeth for high prices to foreign tourists. Great White sharks are protected and it is illegal to kill them or sell any part of them in South Africa. Michael Scholl, a Swiss shark researcher based at Gansbaai, said yesterday he had been offered a single Great White shark tooth for $100. "It's very worrying because the international trade is still legal," he said. "A big White shark jaw can fetch $10 000 in the United States." Yesterday, law enforcement officers searched two curio shops in Hermanus and seized Great White shark teeth that had been made into jewellery. Craig Spencer, Overstrand municipality's conservation chief, said he had received information that a group of perlemoen poachers in Hawston and another group in Gansbaai had turned to Great Whites as a lucrative source of income. "We haven't any evidence of Great White sharks being killed, but their teeth are being sold right here under our noses and they come from somewhere," he said. "This is the first crackdown we've had on selling them. It is an offence and we regard it in a very serious light." Spencer and his newly formed "Marines" anti-poaching unit, made up of municipal conservation staff and Marine and Coastal Management members, searched the shops and with the help of two marine biologists who identified which teeth were those of Great Whites. Jeff Tanner, owner of the shops, said he did not know it was illegal to sell the teeth. He said he had got them from a man at the Hermanus craft market who had said he was supplied by his brother who worked for the Natal Sharks Board. Tanner co-operated with the officials. He was given a R500 admission-of-guilt fine. The officials tracked Tanner's supplier, Tabani Mangena, to the Hermanus curio market. Mangena denied having told Tanner that he got the teeth from a Natal Sharks Board employee. He said he got his supply from "Jerome" who traded on Cape Town's Greenmarket Square. He said he did not sell Great White shark teeth as doing so was illegal. Sheldon Dudley of the sharks board said: "I'm surprised they're being sold openly in the Cape. Our Great White shark teeth are under lock and key. If anyone on our staff is selling them, they will be severely disciplined," Dudley said. Spencer said the shark cage-diving industry was the biggest contributor to gross net product east of Hermanus. White Shark poaching posed a risk to this industry, he said. - Environment Writer


More links of interest
http://www.csiro.au/ Commonwealth Scientific and Industrial Research Organisation Swimming with sharks


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