Porbeagles making comeback

Adam Randell
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It's rare to see a Porbeagle shark off the coast of Newfoundland in the winter, according to Dr. Steven Campana, a scientist with the Bedford Institute of Oceanography, in Nova Scotia. Pictured, Campana kneels beside a porbeagle shark. The shark was tagged with a satellite-tracking device to observe migration patterns. Photo courtesy of Dr. Steven Campana

Over the past two years, Gary Monks, a King's Cove fisherman, has been noticing something in the water he's never seen in his 40 years of fishing - the porbeagle shark.

In the fall of the year until about Christmas, Monks fishes herring. Lately he's been finding porbeagles in his nets.

As of Christmas, 2010, he's had four in his nets.

He told The Packet last week he was able to save one.

"He was twisted up by the tail so I tore a bit of extra net away and was able to get him clear," Monks said.

There was some damage done to his nets by the trapped sharks, but he doesn't hold a grudge.

"They are a bit of nuisance sometimes but it's something you have to live with," he said. "They are just trying to get a bite to eat, the same as we are."

When it comes to a trapped shark in his net, Monks said he's going to do what he can to save its life, even if it means having to repair some of his nets.

To him, to kill something for the sake of killing something is a waste.

According to Dr. Steven Campana, a scientist with the Bedford Institute of Oceanography, it's rare to find porbeagles around Newfoundland waters in the winter.

Campana, who also heads up the Canada shark research lab, said the sharks usually move towards warmer southern waters in fall, and stay there until spring.

He said there is no clear answer as to why porbeagles were still in the area at that time of year, but speculates it may have been because of warmer water temperatures.

"The waters have been warmer in some areas, compared to other years," he said. "It's one of those things that's hard to figure out and we don't have an exact reason for it."

Unique

The porbeagle shark is a family member of the mako and great white species.

It is smaller than the great white but is very similar in appearance. The smaller stature makes it a fast-moving shark.

They are long-lived, slow-growing sharks and can live up to 40 years, explained Campana.

Some of the largest ones have recorded, he said, are over 10 feet long - from the tip of the nose to the fork in the tail - and tipping the scale at 500 pounds.

It has a preference for colder water making it common in Atlantic Waters. The diet consists of fish and squid, can be attributed for its presence off the coast of Newfoundland.

Campana said the diet is very different from the blue shark - also common in Newfoundland waters - known to eat oil filters and tin cans.

Porbeagles are also known to be an open ocean shark, but Campana said there are times when it can be found near the shore.

"I get a lot of calls every summer and fall of people seeing fins close to shore; they are porbeagles just cruising around looking for food."

For the most part he said porbeagles are non-confrontational with humans.

"There have been a couple of incidences where they have gotten a little bit aggressive but they have never bitten anybody," he said. "It's certainly nothing like the sharks you would get down south."

The known areas for porbeagles in Newfoundland and Labrador centre around the Grand Banks and southern Newfoundland.

Campana said Newfoundland is only one of two known breeding grounds for the porbeagle.

Well travelled

The DFO has been researching the species for 15 years or so, and has found two interesting things about the shark's migration pattern.

He said every spring the shark will migrate from the south and into the Atlantic Canada region.

"There is almost like a river of porbeagles that swim up well off the shore of Nova Scotia, swimming in from the Gulf of Main; and spreading throughout Nova Scotia, southern Newfoundland and the Gulf of St. Lawrence," he said.

The sharks will hang around the area until fall and make their way south again.

Through the use of satellite tagging, Campana said they received some really exciting results last year.

The information identified that pregnant porbeagles will swim to the Sargasso sea - more than 2,000 kilometers away - to give birth, and later return to Atlantic waters with their baby in the spring.

Campana said no one knows for sure why they do this. He said baby porbeagles are more than capable of surviving in Atlantic waters because they are born two feet long and have sharp teeth.

"We don't really have an answer, but we think they sort of hitch a ride with the Gulf Stream, in the deeper colder water (column). There is all sorts of squid in that stream and we think it serves as a moving buffet table for them."

He said this is one of few known migration patterns for in sharks.

The porbeagle also holds significance in Atlantic Canada for the simple fact that it is the only large shark in Canada is directed fished.

Campana said the market isn't as strong as it used to be, but added it is very good meat to eat.

The shark's population is estimated to be over 200,000, but that's only a quarter of what it used to be, says Campana.

Until the 1960's there was no fishery for porbeagles, when foreign fishers started coming into Canadian waters and fished the species hard.

"They didn't fish it to the point of extinction, but to the point of commercial extinction," he said. "The numbers stayed low for about 30 years. In the '90's Canadian fishers started fishing them too hard."

That's when research began and the quota was reduced to allow the shark population to recover.

According to the DFO's 2010 Landings and Landed Value report, there was 1,067 pounds of porbeagle landed, at a landed value of $407.

On the mend

With the number of porbeagle sightings growing, Campana said it could mean a good sign of recovery.

The porbeagles are slow-growing sharks. Campana said it would take decades for the species to show strong signs of recovery.

He said the sightings not only mean good things for the shark, but its ecosystem as well.

"It's an apex predator - it eats everything else and nothing eats it - a healthy ecosystem needs that, you got to have them or weird things happen," he said. "If they weren't there it would mean trouble with that ecosystem."

arandell@thepacket.ca

Organizations: The Packet, Bedford Institute of Oceanography, DFO

Geographic location: Newfoundland and Labrador, Atlantic Canada, Southern Newfoundland Nova Scotia Atlantic Waters Gulf Stream

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