The next two months will bring sleepless nights and high anxiety — and quite possibly an extraordinary windfall — for a small universe of people in Maine. They are the lucky few with licenses to catch elvers — young, tiny eels that look like cellophane noodles and by some accounts are fetching up to $2,200 per pound this spring.


Elvers are a hot commodity in Asia, where aquaculture farms grow them to adult size and sell them for sushi and other food. They are believed to spawn in the Sargasso Sea and drift on currents to Maine, where they make their way to fresh water and, from March 22 through May 31, into the waiting nets of some 400 elver fishermen. The action takes place overnight, when elvers are most active.


Maine is one of only two states, along with South Carolina, where elver fishing is still allowed. And with Asian demand especially high — last year’s tsunami curbed supply in Japan, and Europe has cracked down on exporting eels — a gold rush of sorts is on along the rivers and streams of coastal Maine. Since the season began last week, stories have abounded of people making a small fortune in an often hard-luck state.


“The first two days of the season were extremely amazing,” said Bill Quinby, an exporter based in Charleston, S.C., who shipped about 90 pounds of elvers to South Korea on Tuesday after buying them from Maine fishermen. “People were making $30,000, $40,000 a night.”


Takes like that have brought poachers out in force. Gov. Paul R. LePage signed emergency legislation on Thursday increasing fines for unlicensed elver fishing to $2,000, up from a maximum $500. The law also stiffens penalties for catching elvers before the season starts and tampering with the nets that they are caught in. Prices have dropped this week, though they remain far higher than in previous years. David Smith, a licensed elver fisherman from Southwest Harbor, said they were down to about $1,750 per pound, perhaps because the catch was so abundant in the first few days of the season.


“It may be the buyers think, based on Thursday night’s harvest, ‘There’s going to be plenty of eels; we don’t need to pay this kind of money,’ ” Mr. Smith said. “But it may bounce back up. Who knows?”


Asked whether he did well last week, Mr. Smith put it this way: “I’m having a little addition put on my house, and I think I just paid for half the windows and doors.”


Mr. Smith’s wife is usually his only company when he catches elvers from a tributary in a secluded part of Mount Desert Island. But in other parts of the state, fishermen cluster along the banks of some waterways and fight to protect their spots.


“I had to sit there for three days before the season opened, slept in my truck, just to stake out my position,” said John Taylor, an elver fisherman from Newcastle, Me., who did not want the location of his nets revealed. “I had to actually let another guy take the spot — otherwise, he was going to fight me for it. And I wasn’t going to go to jail, knowing what kind of season was ahead of me.”


Elver prices fluctuate from year to year — the creatures brought about $900 per pound last year, some fishermen said, but far less in the past. People often catch between 20 and 40 pounds in a good season, Mr. Smith said, though he has heard rumors of experts landing 50 pounds in one night.


Richard Blake, a longtime buyer, said poachers were coming “right out of the woodwork.” Some unscrupulous types have even tried selling him young eels that he suspects came from other states, he said.


“Most of the eel dealers up here are smart enough to know if the product being offered didn’t come from the state of Maine,” Mr. Blake said. “Anyone that I’m not sure about, I send down the road.” Mr. Quinby said some dealers are “walking around with security because of all the cash they carry from buying elvers in the middle of the night.”


High-end restaurants in the United States sometimes put elvers on the menu, perhaps fried or sautéed in olive oil with garlic. Dan Scofield, a buyer for Pierless Fish, a Brooklyn dealer, said the company had supplied elvers to Daniel in New York, French Laundry in Northern California and other top American restaurants in the past. But, he said, prices this year are too high.


The future of the fishery is not clear: the federal Fish and Wildlife Service is considering listing the American eel as threatened or endangered. Already, elver fishing is not allowed two days each week during the season for conservation purposes.


Mr. Smith, for one, does not mind the break. On some nights during elver season, he fishes until 2 or 3 a.m. and turns to his primary vocation, a crab processing business, at 4 in the morning.


“I inevitably in the next two months will suffer from sleep deprivation,” he said. “There was one spell last year when I got about three hours’ sleep in three days and then my wife took the car keys away.”