Federal regulators slapped a six-month ban on most cod fishing off New England this week and are threatening to cut next year’s catch by up to 75 percent, in a move some say will destroy the livelihoods of fishermen across the region.

Starting Thursday, the National Oceanic and Atmospheric Administration is shutting down cod fishing from Provincetown, Mass., to the Canadian border, as part of a plan to reverse dwindling numbers of cod in the Gulf of Maine. That means no fishermen may trawl in NOAA-designated areas until April 30, 2015. This comes on top of prior efforts by the U.S. and Canadian governments to restrict cod fishing in the nearby Georges Bank. 

NOAA announced several measures, including the ban which expands no-fishing zones, on Monday. But fishermen whose livelihoods rely on catching cod, as well as the coastal communities that depend on money coming in from that industry, worry the new regulations will devastate them. 

“It’s all over! I’m done,” Gloucester-area fisherman Joe Orlando told Boston’s Fox 25. “My grandfather’s done it, my father’s done it. I brought my kids into doing it.” 

Orlando, whose family has been in the business for 40 years, is used to catching 700 to 2,500 pounds per day, he told Fox 25. But with NOAA’s no-fishing zones, coupled with limits on hauls, Orlando says his boat is now too small to make it into the allowable fishing zones which are farther offshore.

"And now I'm left with nothing. I just threw it all away," Orlando, who makes close to $150,000 per year from cod, said. 

Regulators had already cut the 2013 catch limits of cod by 77 percent from the year before to 1,550 metric tons.

NOAA believes cod have been over-fished and the number of cod stocks have dried up. The scientists believe the best shot they have of avoiding a population collapse altogether is enforcing a ban. 

Cod levels have dipped significantly for more than 20 years. Despite plans to rebuild the fish population in the Northeast, cod have failed to rebound and scientists don’t seem to know why.

“This is a stock that is in free fall,” NOAA regional administrator John Bullard told National Public Radio. He added that the numbers were the worst the agency has seen in four decades. 

There are two types of cod that come from the U.S. -- Atlantic and Pacific cod. The new regulations apply only to the Atlantic kind, in the Gulf of Maine. 

Atlantic cod generally is more abundant, and it's unclear whether the federal restrictions would result in prices rising -- or whether Pacific cod would simply take its place in some areas. (In most places, Pacific cod -- a larger fish that produces meatier fillets -- is slightly cheaper than Atlantic cod, which is smaller and sweeter-tasting) The U.S. also imports cod from countries like China, Russia and Iceland. 

The U.S. also is a major cod supplier on the world market, providing more than two-thirds of the world's Pacific cod. 

There have been sweeping fluctuations in cod stocks, and federal regulations for fishing them, for decades. NOAA officials, in response to industry concerns, last year tried to cushion the financial blow to fishermen by increasing the quota for haddock. Congress this year also approved more than $33 million in aid for the fishing industry in New England. 

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