Canadian Shark Survey Aims to Protect Species From Overfishing

Amid growing global concern about the decline of shark stocks, Canada is undertaking a survey of shark populations in Atlantic Canadian waters. Research focuses primarily on the porbeagle shark and other species commonly found in the area including shortfin mako, spiny dogfish and blue sharks.

Survey results are expected to determine the distribution of shark population in the Atlantic Ocean, including the areas where sharks are born. With this knowledge, Canada will be able to further its shark conservation efforts.

The survey was developed by the Canadian Shark Research Laboratory at the Bedford Institute of Oceanography, in co-operation with commercial fishers representing the Atlantic Shark Association. Fisheries and Oceans Canada provided funding for the survey as part of its commitment to enhance data collection and scientific research on sharks. This is one of the six main action areas outlined in Canada’s National Plan of Action for the Conservation and Management of Sharks that was published in March 2007.

During the first phase of the survey, which was completed on July 12, 2007, six commercial fishing vessels fished for sharks over several weeks in an area spanning more than 200,000 square kilometres from the Canada-US border to northern Newfoundland. They used 15-kilometre lines with baited hooks at different intervals. Captured sharks were brought on board to be measured, examined and tagged by scientists before being released.

Researchers used both conventional and satellite tagging. Conventional tags were placed on young sharks, while satellite tags were reserved for adult sharks − especially adult females. The satellite tags will record data about the shark’s swimming depth, as well as the water temperature and light levels.

The second phase of the survey will involve monitoring tagged sharks to identify the distribution of sharks within the water and the location of birthing grounds. Results of the survey will be made public in Fall 2007.

Additional surveys of shark populations in Atlantic Canada are planned in 2009, and every five years following.

Additional Information:

• National Plan of Action on for the Conservation and Management of Sharks
• Finding the Facts on Fish – Porbeagle and Spiny dogfish sharks
• Bedford Institute of Oceanography