JUNEAU, Alaska — Leaping fuel prices are sinking the fortunes of America's commercial fishermen, some of whom may soon call it quits for good.

In Alaska, boats that typically haul in rockfish and perch sit docked for prolonged periods. In Texas, shrimpers are traveling to Mexico just to buy cheaper diesel. And along the East Coast, lobstermen are making fewer trips to their traps.

Unlike shippers, commercial airlines and other industries that pass higher fuel costs along to customers, fishermen don't have the same flexibility. Not only does fresh fish have a short shelf life, but U.S. families can easily substitute their diets with less expensive chicken, pork and beef — even at a time when the cost of meat is on the rise.

"Fishermen can't come in and say, 'My costs just went up, so you're going to have to pay me more,' " said Bill Adler, executive director for the Massachusetts Lobstermen's Association. Instead, the dealer offers a price and it's "take it or leave it. He knows you got a product that has to be alive. He knows you've got to get rid of them."

U.S. fishermen have in recent years faced increasing pressure to keep prices down because of low-cost imports and farmed fish. The 64 percent rise in the cost of diesel over the past year — with spikes of as much as 75 percent in some parts of Alaska — means already-tight profit margins are being stretched even further, leaving less take-home pay for captains and crews.

"It's as bad as I've ever seen, and I've been at it 45 years," said Jimmie Ruhle, president of the trade group Commercial Fishermen of America and a third generation fisherman out of Wanchese, N.C.

No one is predicting an industry collapse just yet, but fishermen and seafood economists say conditions have deteriorated to the point where some captains are considering leaving the business.

While fishermen in Europe and Asia have staged disruptive protests over the financial damage high fuel prices are causing, their counterparts in the U.S. are hopeful that communications with Congress will lead lawmakers to take action.

"We haven't resorted to blocking our ports in protest like France and Spain. We're not asking for handouts," said Sara Stoner, a Petersburg, Alaska, boat captain who sent a petition to Congress seeking federal assistance with tax relief or low-interest loans.

U.S. Sen. Lisa Murkowski, R-Alaska, on Thursday introduced legislation that would provide commercial fishermen a temporary income tax credit to help them offset the high cost of fuel.

Alaska Gov. Sarah Palin last week asked the state Legislature to offer low-interest loans to local fishermen looking to purchase fuel-efficient engines.

Such measures would no doubt help the industry over the long run, but "in the short-run people will go out of business," said University of Alaska fisheries economist Gunnar Knapp.

That's a worry for Kodiak, Alaska, fisherman Jeff Scott. Instead of being out on the sea gathering perch or rockfish, a 42 percent increase in the cost of diesel in the past six months prompted him to tie up his boat for nearly two months.

"We are rapidly coming up on the breaking point," said Scott, who sounded desperate after a brief trip to sea this week.

"Last year, I had a blind eye to fuel prices. This year, it's the first thing I think about when I leave the house other than the safety of my crew."

To keep their costs down, fishermen from Florida to Texas are increasingly willing to travel to Mexico to fuel up.

Carlton Reyes, president of the Brownsville-Port Isabel Shrimp Producers Association in Texas, said some shrimp boats are traveling to Tampico, Tamaulipas, Mexico — 30 hours each way — to buy fuel.

"If we weren't able to do that, our industry would have collapsed six months ago," he said.

Other fishermen are conserving fuel by making fewer trips, reducing boat speeds, or not traveling as far out.

Long-liner Peter Taylor of Chatham, Mass., says slower travel allows him to nearly halve the 450 gallons of diesel he normally would need on a trip to catch cod or haddock. That also means more time at sea and less sleep.

"It cuts into my time at home," Taylor said. "It also makes it tougher to find a crew.

"It won't take much more of this to put a lot of people out of business."