DURHAM – Giant bluefin tuna fisheries in the Gulf of Maine are in danger of collapse, with the number of fish declining markedly in recent years, according to University of New Hampshire researchers. {recisely why the numbers of bluefins are falling is unclear, but UNH researchers say it is likely the result of a number of factors, including over-fishing from European countries in the Eastern Atlantic and the Mediterranean Sea and shifts in migration and foraging patterns due to global warming.
Although the cause of the decline, both in the number and quality of fish, is uncertain, the effects are obvious.
In the mid-1990s, UNH scientists documented 500 to 900 schools of bluefin tuna in the Gulf of Maine averaging 100 to 150 fish each, said Molly Lutcavage, director of UNH's Large Pelagics Research Center. She said only a "few" schools would be seen in today's waters. "The horrifying reality is that the huge decline in abundance happened so quickly," she said.
The toll is evident in the number of commercial tuna fishing permits, says Rich Ruais, executive director of the East Coast Tuna Association, who estimates that in the mid-1990s, there were 15,000 permits from Maine down to Texas, where today there are about 4,400.
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