Department of Fisheries and Oceans research scientist Dr. Gary Melvin is leading a study into determining how abundant bluefin tuna are in the Gulf of St. Lawrence.
In mid-September, Melvin and researchers conducted hydroacoustic studies in North Lake, Prince Edward Island to obtain data on bluefin populations.
The crew deployed an underwater, multi-beam sonar technology to locate the tuna.
Melvin wants to see if the sonar can accurately define not only the number, but the size and distribution of bluefin tuna in the water.
“The results look promising. We can see them quite clearly,” Melvin said.
“We’ve been around the herring fleet and the recreational fleet for bluefin tuna and we can see what’s under the boats and see what’s there.”
Melvin said last year the crew saw 35 to 40 bluefin tuna around one of the herring fishing boats.
The information obtained will be used to develop a survey at the request of the International Commission for the Conservation of the Atlantic Tunas (ICCAT).
This organization is responsible for the management and conservation of all tuna species in the Atlantic Ocean.
“ICCAT has been expressing concern about the indices of abundance that we are currently using that are based on information from the fishing industry,” said Melvin, who is the lead scientist for ICCAT in Canada.
“Any change in the fishing pattern or the behaviour or regulations can have an impact on those indices.”
Melvin continued, saying the main thrust of the survey will be to establish an index of abundance for the bluefin tuna stocks.
“We are looking at trends and abundance. Is the abundance of bluefin tuna in the Gulf of St. Lawrence going up or down or remaining relatively stable?”
Melvin says everyone is hopeful that the stocks will increase, but he cautions that this is a long-term commitment.
“We are looking at eight to 10 years before the data will actually be able to be used in an analytical model.”
At this point, Melvin and his research team are testing the equipment to make sure it does what they want it to before a substantial amount of money is invested in a larger survey.
“It is the early stages but the results are very positive.”
Melvin says there is sufficient information that gave them confidence the equipment would work as they hoped. Now they will seek funding to invest in more equipment for a larger survey.
Bluefin tuna stocks have been gradually increasing since 2008.