Monday, July 23, 2007

Is the Great White shark possibly facing extinction?

Concerns over the declining shark population of Canada’s East Coast has prompted a survey to find ways to better protect the animals.

The Bedford Institute of Oceanography in Dartmouth, N.S., is doing the province’s first-ever shark survey, headed by scientist Steven Campana, who is in charge of the department’s shark research lab.

"We are working closely with the commercial shark fishery," said Campana. "We have laid out a series of locations up and down the East Coast."

Results collected this month will help map out the distribution of the sharks and also give a good indication of their numbers in local waters, he added.

Young sharks and females are captured and released and the mature females are implanted with satellite tracking tags that will hopefully allow the team to identify the animals’ birthing ground.
"If we can find the pupping ground and if it needs to be protected, then probably, that is what we would do," Campana said, noting shark populations worldwide are declining, some of them to an extreme point.

"It’s quite possible in our lifetime the great white shark will go extinct."

The porbeagle, commonly seen off Cape Breton and a cousin of the mako and great white shark, is a cold water shark.

Porbeagles average two metres in length and usually weigh about 200 pounds.

"Its population is definitely down considerably from when they started getting fished in the 1960s," Campana said.

The survey will give the federal Fisheries Department baseline data to monitor the sharks’ recovery.

"It is our understanding the quotas are low enough to allow the population to recover."

Campana said he regularly gets calls about shark sightings in Cape Breton waters, including an Ingonish resident last week who saw a couple of porbeagle sharks, probably feeding, just off shore.

The waters around Cape Breton also draw basking sharks and spiny dogfish.

Blue sharks can be found further offshore.

There was only one recorded shark attack and that happened off Fourchu in July 1953, when a boat was bitten and sank, dumping the two fishermen in the water.

The fishermen were not attacked but one man drowned attempting to swim ashore.

A tooth left embedded in the planking was identified as that of a white shark.

Sydney diver Ken Jardine has only seen three sharks during his regular dives at locations around the island, including an injured one that had beached itself at Little Lorraine.

Attempts to rescue it failed.

The most exciting sighting was a six-metre basking shark in St. Peter’s Bay when he was returning from a wreck diving expedition.

"We stopped the boat and it came toward us, about 10 feet away, very slowly," said Jardine.
"He was literally the size of a half-tonne pickup truck."


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