Bluefin tuna study nears completion
An international team of researchers is working on a paper on the state of adult Atlantic bluefin tuna and their prey, particularly herring. The paper will soon be submitted to the journal Marine Biology.
The team is lead by the University of New Hampshire’s Large Pelagics Research Center.
The paper was spurred on by commercial fishermen’s interest in bluefin tuna’s diet, their fat content and their habitat. Researchers are tracking the eating habits of giant bluefin tuna via direct observation, measurement and statistical analysis and applying trophic indicators such as stable isotope ratios, fatty acids and lipid content of tissue.
As part of the study, researchers observed the eating habits of bluefin tuna off Virginia’s Eastern Shore, where fish fed almost entirely on sand eels. They also observed individual fish foraging on both sides of the Atlantic: some one- to two-year-old fish tagged in Europe’s Bay of Biscay by Spanish scientists were recaptured within a year or two by Cape Cod fishermen off Massachusetts, while some fish tagged off New Jersey were recaptured in the Bay of Biscay.
With the help of AZTI Tecnalia in Gipuzkoa and the Spanish Institute of Oceanography in Santander, both in northern Spain, the Large Pelagics Center is using pop-up satellite tags and implanted data storage tags to track fish. The center called on the Department of Animal and Vegetal Biology & Ecology in Cadiz, in southern Spain, to help it compare the spawning status and reproduction cycle of Atlantic bluefin tuna with Mediterranean bluefin tuna.
“We’ve been impressed with the breadth and strength of the Spanish Atlantic bluefin tuna research, and I’m very pleased to be able to collaborate with these talented colleagues,” said Dr. Molly Lutcavage, director and associate research professor at the Large Pelagics Research Center.