PORTLAND, Maine — The Gulf of Maine shrimp fishing season could be a short one with the 2012 catch limited to a third of the 2011 harvest.

Shrimp fishermen have been given a catch limit of 4.4 million pounds for the season, down from the 13 million pounds they caught last season. The new season begins Monday and will end when the catch limit is reached.

Scientists say lower catch limits are needed because shrimp are being overfished, and the supply is declining. But fishermen say their livelihoods are at stake, and processors are worried that markets they’ve built for the small, sweet shrimp will be put at risk because they won’t have enough product to fill orders.

Fishermen are expecting decent prices, but there also will be “dire economic consequences” with so little shrimp to go around, said Maggie Raymond, executive director of Associated Fisheries of Maine.

“I predict it’ll be a miracle if they get through the end of January,” Raymond said. “I can’t see there being anything left in February.”

Found in the cold waters of the Gulf of Maine, northern shrimp provide a winter fishery for hundreds of New England fishermen. Boats from Maine typically catch about 90 percent of the annual harvest, with small numbers from New Hampshire and Massachusetts catching the rest.

The shrimp population varies, and regulators each year set limits on how much can be caught. The season was cut short in each of the past two years because fishermen surpassed the target, by 28 percent in 2010 and 48 percent this year.

The Atlantic States Marine Fisheries Commission based this coming season’s lower catch on scientific surveys that showed a decline in the shrimp population. The catch limit was set despite objections by fishermen and processors.

Net fishermen can only fish three days a week — Monday, Wednesday and Friday — while those who use traps to catch shrimp can’t do so until February and will be limited to 1,000 pounds per day per boat, said Michael Waine, a fisheries management coordinator with the commission.

“The intent is to slow the shrimp harvest to spread out the landings to extend the season,” Waine said.

Fishery managers also are trying to keep closer tabs on the harvest. For the first time, shrimp dealers are being required to report numbers on a weekly basis, rather than monthly, so that regulators will know in a timely manner when the catch limits are being approached.

The ASMFC’s shrimp panel will meet Jan. 19 to evaluate where the harvest stands and possibly modify or adopt new regulations — such as trip limits for net fishermen — to slow down the catch rate even more if deemed necessary.

Not everybody agrees that such a small catch limit is necessary, said John Norton, owner of Cozy Harbor Seafood in Portland.

Fishermen have been seeing an abundance of shrimp the past couple of years, he said, and a group of processors is petitioning the commission’s shrimp panel to consider raising the catch limit when it meets Jan. 19. Another stock assessment formula suggests that fishermen could catch nearly 10 million pounds of shrimp this season without putting the stocks at risk, he said.

The shrimp industry in Maine employs more than 1,500 people, from fishermen and workers who help unload boats to truck drivers and processors, he said. Cozy Harbor alone employs 130 to 140 workers during shrimp season to process and pack shrimp bound for New England, West Coast and European markets.

“I’m just astounded that with the economic conditions we have in this state and this country that we’re giving up those jobs and giving up those paychecks,” Norton said. “It doesn’t make any sense to me.”

Many fishermen think now is the time for regulators to institute a “limited entry” system that restricts how many fishermen can get shrimp fishing licenses, based on their history of shrimp fishing.

Supporters say controlling the number of boats in the fishery will help keep the shrimp population at sustainable levels. Opponents say a limited-entry system would shut many lobstermen and others out of the fishery and change the culture of coastal communities by further limiting their ability to patch together a living when pickings are slim.

Regulators are now discussing the possibility of instituting a limited-entry system.