2023-11-14 23:39:42
White shark detection tools have multiplied in recent years. Technological advances now make it possible to document with more precision the presence of these predators which sometimes frequent areas of Gaspésie, the Magdalen Islands and the North Shore.
For the first time this year, satellite transmitters were placed on white sharks in Quebec waters.
A shark named Simon approached Anticosti Island and the village of Rivière-au-Tonnerre this summer and fall. No one saw him, but his presence was detected by satellite.
The American company Ocearch places tags on white sharks. Since its creation, 437 sharks have been equipped with a device allowing them to be tracked.
In Simon’s case, he left the waters off the coast of the state of Georgia in December 2023. During the winter, he slowly progressed northward, reaching Canadian waters in July. This fall, he spent a few weeks off the North Shore before returning to warmer waters. This 9-foot-6-inch male came all this way to eat, among other things, gray seals which are found in abundance in the St. Lawrence, indicated Maurice Lamontagne Institute researcher Xavier Bordeleau.
“These are animals that migrate to Canadian waters to feed in the summer. What was perhaps more surprising was the detection on the North Shore,” he explained.
With their network of fixed hydrophones, Fisheries and Oceans Canada researchers detected 47 different white sharks in the Gulf of St. Lawrence in 2022. For the first time this year, sharks were equipped with transmitters while they were in Quebec waters, near the Magdalen Islands.
“We managed to tag nine white sharks with a combination of satellite and acoustic transmitters. It takes our research program to another level,” said Xavier Bordeleau.
Canadian researchers can thus strengthen their collaboration with their American colleagues concerned about this endangered species. The population of white sharks is said to have decreased by more than 70% between the 60s and 90s. A recent study shows a gradual increase in the population, but scientists are not certain, hence the interest in increasing the number of tools technology to count them.
“We know that in recent years, this is the subject of our research, we also try to quantify. Are there really more than there were 5 or 10 years ago for example? We are starting to have data to test these questions.”
The first documented sighting of a great white shark in Canada dates back to 1874, off the coast of Newfoundland.
Over the next hundred years, the presence of these famous fish at the top of the food chain was reported only about a hundred times in Canadian waters.
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