generalspeaking

Tagging The Beast

"This was our second tagging attempt in Canadian waters."
"To 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 Canada, although we have had information from tags applied in the U.S. that have come to Canadian waters previous to this."
"We will have to wait patiently, but when the tag does pop off, we'll be able to analyze its depth and temperature use relative to some ocean current modelling that's been done, to look at both where it was in Canada as well as how it was behaving, how close it was to the coast, as well as what its behaviour might have been."
"There have been more sightings of whites up in around Canada. There's more tagging effort as well and so there's been more tag detections."
"But there's been no population size estimate for white sharks in the North Atlantic, so it's unknown whether this represents substantial population increase." 
"We would have information on things like swimming speed and those types of questions."
Heather Bowlby, researcher, Bedford Institute of Oceanography, Halifax

A great white shark was tagged in the waters off southwest Nova Scotia last week. (Department of Fisheries and Oceans)

"We started having bait being taken from us."
"Nathan was the one who actually seen [sic] this splashing and white water all over the place --- and so we went racing over there and that's 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."
"[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. So it was quite a little fright that he had."
"There was one time where the fish tail came up and whacked the side of the boat. It's amazing the adrenalin that will start going through your body once everything starts happening."
Art Gaetan, skipper, charter boat, Eastern Passage

The purpose of tagging the lone great white shark, a juvenile predator seen off the coast of Nova Scotia, was to improve scientific understanding of this particular beast's movements off Canada. Tagging would provide an information assist to understand where white sharks move while in Canadian waters, informing recovery and protection efforts. This is a critical issue since white sharks are listed as endangered in the Canadian Species At Risk Act.

Anticipating that data collected from the archival tag will not be available for nine months, a gestationary period where eventually the tag will pop off the shark and float to the surface. When it does, it will transmit the vital information to a satellite. It was important that minimal interaction with the shark take place while the tagging was going on. It did so swiftly, in the water for minimal impact on the beast's behaviour in hopes of being able to "get the best information possible."

It is entirely possible, according to Dr. Bowlby, that greater numbers of white sharks are moving into Canadian waters. While working at the Bedford Institute of Oceanography in a team of three researchers, she often collaborates with other organizations equally interested in the welfare of the species. The team held off naming the white shark caught last week which they estimated to be about twenty years old. Naming was withheld until the completion of a photo identification catalogue in development in the United States where photos of its dorsal fin had been sent to determine whether it has already been named.

An American group, Ocearch, is now operating in Nova Scotia on shark research with the intention of tagging mature females to track them to a birthing site. Ocearch tagged a celebrity great white shark named Hilton who was tracked off Cape Breton on Saturday. Hilton has its own Twitter feed with close to 45,000 followers. Did he but know!

For the first time in Atlantic Canadian waters, scientists have successfully tagged a great white shark. Hilton the great white shark is shown being tagged in March of 2017 in Hilton Head, S.C. Hilton has travelled from the Gulf of Mexico in the spring to the coast of Nova Scotia this summer. - Contributed

Labels: Biology, Great White Shark, Nova Scotia, Oceanic Wildlife, Research

posted by Pieface @ Friday, September 21, 2018