HALIFAX 鈥� For the first time in Atlantic Canadian waters, scientists have tagged a great white shark in an effort to better understand the predator鈥檚 movements off sa国际传媒.
Heather Bowlby, a researcher with the federal government鈥檚 Bedford Institute of Oceanography in Halifax, said the three-metre juvenile male shark was satellite-tagged off southwest Nova Scotia last week.
鈥淭his was our second tagging attempt in Canadian waters,鈥� said Bowlby, standing on the same charter boat used to tag the shark, docked Tuesday in a fishing village in Eastern Passage.
鈥淭o our knowledge, this is the first time that an archival satellite tag or any type of satellite tag has been applied to a white shark while in sa国际传媒, although we have had information from tags applied in the U.S. that have come to Canadian waters previous to this.鈥�
Bowlby said the tag information will assist in understanding where white sharks move in Canadian waters, and help inform recovery and protection efforts. White sharks are listed as endangered in sa国际传媒鈥檚 Species At Risk Act.
She said data collected from the archival tag will not be known for nine months 鈥� it will pop off and float to the surface at that time and transmit the information to a satellite.
鈥淲e will have to wait patiently, but when the tag does pop off, we鈥檒l be able to analyze its depth and temperature use relative to some ocean current modelling that鈥檚 been done, to look at both where it was in sa国际传媒 as well as how it was behaving, how close it was to the coast, as well as what its behaviour might have been,鈥� said Bowlby.
鈥淲e would have information on things like swimming speed and those types of questions.鈥�
Bowlby said she wanted to have minimal interaction with the shark, with the tagging happening very quickly and in the water, to ensure the team had minimal impact on its behaviour to 鈥済et the best information possible.鈥�
Bowlby, along with skipper Art Gaetan and first mate Nathan Glenn of Blue Shark Charters, set off on the mission last Monday in Gaetan鈥檚 11-metre boat, using a slick of ground-up fish and tuna heads to attract the large fish.
Hours were spent simply watching buoys, looking for signs of a white shark.
On day two, they caught their first glimpse.
鈥淲e started having bait being taken from us,鈥� said Gaetan, as dozens of seagulls screeched overhead under sunny skies.
鈥淣athan was the one who actually seen this splashing and white water all over the place ... and so we went racing over there and that鈥檚 when we pretty much got our confirmation that it had been a white shark. He had taken the bait, bit the line off, and was swimming around the red float for a bit and then left.鈥�
The next day, Glenn came face-to-face with the toothy fish.
鈥�(Nathan) had come back to check a bucket to give it a shake for a drift, and when he went back and looked over the side, mister man was looking at him,鈥� said Gaetan.
鈥淪o it was quite a little fright that he had.鈥�
The team put the rest of their bait into the water and were eventually able to hook the 900-pound shark alongside the boat, and tagged him.
The whole process took three to five minutes, 鈥渂ut it felt like about three to five days,鈥� said Gaetan. 鈥淭here was one time where the fish tail came up and whacked the side of the boat,鈥� he said. 鈥淚t鈥檚 amazing the adrenaline that will start going through your body once everything starts happening.鈥�
It鈥檚 an experience Gaetan won鈥檛 soon forget: 鈥淚 am complete,鈥� he quipped.
Bowlby said it鈥檚 possible more great white sharks are coming to Canadian waters.
鈥淭here have been more sightings of whites up in around sa国际传媒. There鈥檚 more tagging effort, as well and so there鈥檚 been more tag detections,鈥� said Bowlby, who works at the Bedford Institute of Oceanography in a team of three, but frequently collaborates with other organizations.
鈥淏ut there鈥檚 been no population size estimate for white shark in the North Atlantic, so it鈥檚 unknown whether this represents substantial population increase.鈥�
The white shark caught last week, estimated to be about 20 years old, was not named by the team. Bowlby said there is a photo identification catalogue being developed in the U.S.,
and so photos of its dorsal fin were sent down to see if it has already been named.
The news comes as Ocearch, an American group, is in Nova Scotia to begin shark research, hoping to tag some mature females and track them to a birthing site.
Ocearch is best-known in Nova Scotia for tagging Hilton, a celebrity great white shark who regularly reveals his location in a wry and charming Twitter feed that has almost 45,000 followers.
