The first acoustic tag-bearing great white shark to visit Nova Scotia waters this spring has been detected in the Minas Basin.
Darren Porter, a member of the Fundy United Federation of Fishermen, is keenly interested in science and so has worked with researchers by putting out buoys equipped with receivers that detect the signals from the tags on the sharks.
The ping from the tag on a shark known as Andale was recorded on June 11. So far, Porter’s only downloaded one day of data but said there’s a lot of information to go through.
The shark was tagged in 2012 off the coast of Massachusetts by Greg Skomal and John Chisholm, researchers with that state’s division of marine fisheries, Porter pointed out. Skomal and Chisholm were not available for comment.
“For me, I just love doing it,” Porter said. “I have 42 acoustic receivers out right now, which is probably the largest array of anybody besides (the Ocean Tracking Network), that I can think of.”
Porter also recorded the first signal of last spring when another great white, known as Pumpkin, visited the area.
“Pumpkin last year broke the record for the earliest ever recorded white shark in the Bay of Fundy and Andale beat her this year. So now we have new evidence of even two weeks earlier sharks being here,” Porter said.
All he has to do is bring his boat up to the buoy, take it out of the water and transfer the data to hiscomputer via Bluetooth wireless.
In the Minas Passage, the receivers can detect a ping within 400 metres. In calmer waters, the range would be about 1,000 metres, he said. With multiple receivers, the data will show the path the shark takes. It worked well for Porter to track Pumpkin’s path last year.
“This is just the beginning of what we’re going to see this year,” he said. “There was a great big one that was seen off Grand Manan and they’re working their way up this way. And there’s guys reporting buoys being bit in the last two weeks like you wouldn’t believe, there’s people watching seagulls being taken (out) of Scots Bay — they’re all coming.”
Fred Whoriskey, executive director of the Ocean Tracking Network at Dalhousie University, said researchers have had a number of reports of tagged great whites coming into the Bay of Fundy.
“It looks like the white shark populations are rebounding in the North Atlantic at this point in time and we’re beginning to see these penetrations and detections of these animals in these particular areas, so probably a good news story about the white shark populationsrebounding,” Whoriskey said.
“June sounds early but they’re after the food, so if the food is moving, they’ll come calling.”
Whoriskey hasn’t had a chance to look up Andale’s particulars. Details about the shark’s estimated size were not immediately available.
Whoriskey said great whites, like mako and porbeagle sharks, can recapture the heat produced by muscle contractions to warm their core, which lets them enter colder waters than other animals would.
Porter, who also runs a fishing weir and helps students with their research, said he provides the raw data to First Nations groups and the Department of Fisheries and Oceans as well as researchers.
“It’s just a wonderful start up in the upper bay,” he said. “Up here, in the Minas Basin, we’re all starting to work together and the amount of information we’ve produced because we’re working together is phenomenal.”
Big Moon Power, a tidal energy firm funds Porter’s acoustic receiver project. The company that makes the acoustic tag, VEMCO, is based in Bedford.
“This is a Nova Scotia story,” Porter said. “And people should know we’re the ones leading that technology.”
