Great white’s journey from SA to Mozambique

Published Oct 23, 2012

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Cape Town - A great white shark fitted with a satellite tag in Mossel Bay about seven months ago made her way all along the coast to Mozambique – where she was captured and probably killed.

The tag on the female shark, named Brenda Fassie, has been transmitting signals from a village in southern Mozambique for a period of nearly two weeks.

On the online Ocearch Global Shark Tracker, which tracks more than 30 tagged sharks, the movement of her tag is clearly plotted.

At the end of last month, based on dots showing where signal was transmitted from, Brenda swam around the Mozambique Channel.

On October 4, she was near the shoreline and a line from this point shows her tag was moved to an area near the village of Quissico in the Inhambane area of Mozambique.

A number of dots plotted in the village show how her tag has moved around daily.

When zoomed in on, the map shows that at 5.53am on Wednesday, the tag transmitted a signal near a hut and palm trees.

Ryan Johnson, a director at Oceans Research who helped initially capture and tag the shark and who named her Brenda Fassie after the late South African singer, said he believed she had been killed.

He said the satellite tag had been bolted on to her fin.

“You can’t manually pull it off. It’s not designed to fall off,” Johnson said.

The tag would probably only have fallen off in a few years and he said if it had accidentally come off in the water, it would have sunk and the tag would have transmitted a signal from this point.

Johnson described Brenda as a “really cool shark” who had been strong on her release after being tagged.

Unlike in SA, great white sharks are not protected in Mozambique and it is not illegal to catch them there, making them vulnerable.

Johnson said the national protection of great white sharks was therefore not sufficient.

“Brenda is the tragic consequence that has proven this point,” he said.

Despite great whites being protected in this country, Johnson said the size of the population was decreasing and this could be because the sharks’ home range was bigger than SA and they were being captured in other waters.

He said in the next few weeks a number of sharks would probably be at greater risk of being captured and killed as they would migrate towards Durban and possibly up to Mozambique, which had a reputation for being a shark fishing hot spot.

Alison Kock, research manager for Shark Spotters, said for nearly two weeks researchers had been trying to get others in Mozambique to determine how Brenda was captured – whether she was accidentally caught or targeted.

She said based on the satellite tag data, Brenda had “definitely” been captured.

“We expected this to happen... One of our aims of research is the idea of mortality these sharks are facing out of South African water,” Kock said.

She said Brenda was one of two tagged sharks who swam up to Mozambique.

Kock confirmed her satellite tag was transmitting a signal daily and “must be in someone’s village”.

On the Ocearch Global Shark Tracker website, it gave a profile of Brenda, who was tagged on March 8 in Mossel Bay.

It described her life stage as “immature” and said she was more than three metres long and weighed 594kg.

In the Great White Shark Blog on the Dyer Island Conservation Trust website, it said aside from Brenda, another shark named Cyndi, tagged in Gansbaai, headed so far south that at one point she was closer to Antarctica than SA.

Another shark tagged in De Hoop, Maureen, headed towards Australia before returning to SA.

“This data is unprecedented,” the blog said. - Cape Times

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