Ale Nodye, the son and grandson of fishermen in this northern Senegalese village, said that for the past six years he netted barely enough fish to buy fuel for his boat. So he jumped at the chance for a new beginning. He volunteered to captain a wooden canoe full of 87 Africans to the Canary Islands in the hopes of making their way illegally to Europe.
The 2006 voyage ended badly. He and his passengers were arrested and deported. His cousin died on a similar mission not long afterward.
Nonetheless, Mr. Nodye, 27, said he intended to try again.
I could be a fisherman there, he said. Life is better there. There are no fish in the sea here anymore.
Many scientists agree. A vast flotilla of industrial trawlers from the European Union, China, Russia and elsewhere, together with an abundance of local boats, have so thoroughly scoured northwest Africas ocean floor that major fish populations are collapsing.
That has crippled coastal economies and added to the surge of illegal migrants who brave the high seas in wooden pirogues hoping to reach Europe. While reasons for immigration are as varied as fish species, Europes lure has clearly intensified as northwest Africas fish population has dwindled.
Last year roughly 31,000 Africans tried to reach the Canary Islands, a prime transit point to Europe, in more than 900 boats. About 6,000 died or disappeared, according to one estimate cited by the United Nations.
The regions governments bear much of the blame for their fisheries decline. Many have allowed a desire for money from foreign fleets to override concern about the long-term health of their fisheries. Illegal fishermen are notoriously common; efforts to control fishing, rare.
But in the view of West African fishermen, Europe is having its fish and eating them, too. Their own waters largely fished out, European nations have steered their heavily subsidized fleets to Africa.
As Europe has sought to manage its fisheries and to limit its fishing, what weve done is to export the overfishing problem elsewhere, particularly to Africa, said Steve Trent, executive director of the European Justice Foundation, a research group.
European Union officials insist that their bloc, which has negotiated fishing deals with Africa since 1979, is a scapegoat for Africas management failures and the misdeeds of other foreign fleets. They argue that African officials oversell fishing rights, inflate potential catches and allow pirate vessels and local boats free rein in breeding grounds.
Pierre Chavance, a scientist with the French Institute for Research and Development, said both foreign fleets and African governments allowed financial considerations to trump concerns for fish or local fishermen.
One side has a big interest to sell, and the other side has a big interest to buy, he said. The negotiations are based upon what people want to hear, not the reality.
Overfishing is hardly limited to African waters. Worldwide, the United Nations Food and Agriculture Organization estimates that 75 percent of fish stocks are overfished or fished to their maximum. But in a poor region like northwest Africa, the consequences are particularly stark.
Fish are the main source of protein for much of the region, but some species are now so scarce that the poor can no longer afford them, said Pierre Failler, senior research fellow for the British Center for Economics and Management of Aquatic Resources.
The coastal stock of bottom-dwelling fish is just a quarter of what it was 25 years ago, studies show. Already, scientists say, the seas ecological balance has shifted as species lower on the food chain replace some above them.
In Mauritania, lobsters vanished years ago. The catch of octopus -- now the most valuable species -- is four-fifths of what it should be if it were not overexploited. A 2002 report by the European Commission found that the most marketable fish species off the coast of Senegal were close to collapse -- essentially sliding toward extinction.
The sea is being emptied, said Moctar Ba, a consultant who once led scientific research programs for Mauritania and West Africa.
In a region where at least 200,000 people depend on the sea for their livelihoods, local investments in fishing industries are drying up with the fish stocks. In Guinea-Bissau, fishermen who were buying more boats less than a decade ago now complain they are in debt and looking to get out of the business.
Before, my whole family could live on what we caught in one pirogue, said Niadye Diouf, 28, whose Senegalese family sold their pirogue for $500 to pay for an illegal -- and ultimately unsuccessful -- voyage to Spain. Now even five pirogues would not be enough.
Fishermen like Mr. Diouf argue that Africans should have first priority in their own waters -- an idea enshrined in a 1994 United Nations treaty on the seas that acknowledges the right of local governments to sell foreigners fishing rights only to their surplus stocks.
But that rule has been repeatedly violated along northwest Africas nearly 2,000-mile coast.
Studies dating to 1991 indicated that Senegals fishery was in trouble. In 2002, a scientific report commissioned by the European Union stated that the biomass of important species had declined by three-fourths in 15 years -- a finding the authors said should cause significant alarm.
But the week the report was issued, European Union officials signed a new four-year fishing deal with Senegal, agreeing to pay $16 million a year to fish for bottom-dwelling species and tuna.
Four years later, Mauritania followed suit. Despite reports that octopus were overfished by nearly a third, in 2006 Mauritanias government sold six more years access to 43 European Union vessels for $146 million a year -- the equivalent of nearly a fifth of Mauritanias government budget.
I dont know a government in the region that can say no, said Mr. Chavance, the French scientist. This is good money, and they need it.
Sid-Ahmed Ould-Abeid, who leads a Mauritanian association of small fishermen, said: The EU has the money, so it has the power. It is easier to sacrifice the local fishermen.
Those sacrifices are multiplying in Mauritania. One of the few countries with a private industrial fleet, most of it jointly owned with the Chinese, it has lost one-third of roughly 150 trawlers since 1996.
Ahmed and Mohamed Cherif, whose family owns P.C.A., a fish exporting firm in Nouadhibou, say they have lost money for two years running. Their two new orange trawlers spend weeks docked in Nouadhibous rough-hewn harbor.
We cant compete with the European Union, Ahmed Cherif said as he strolled past row after row of idle pirogues. The government should have kept this resource for Mauritanians. Let these people work.
Europe is just one foreign contributor to fish declines. Countries from Asia and the former Soviet Union also dispatched ships to ply northwest Africas seas. But often those fleets stay for shorter durations and without the same promises of responsible fishing and local development.
In fact, little development has taken place since the European Union signed its first fish deal with a West African nation in 1979. The huge economic benefits that come from processing and exporting the catch remain firmly in European hands.
African governments either misspent or diverted the funds earmarked for development to more pressing needs, while the Europeans sometimes made only token efforts on promised projects. Nouadhibou harbor, for instance, remains littered with 107 wrecked fishing trawlers eight years after the European Union promised to clear them to help develop the port.
In their defense, European officials say they moved to reform their fishing agreements in 2003 to address criticism that ship operators were overfishing and were undercutting local fishermen. Fabrizio Donatella, who heads the European Union unit that negotiates fishing deals, says the new agreements are models of responsible fishing and transparency.
One cannot say we are not fishing the surplus or that we have not respected scientific recommendations, he said. Ultimately, African governments must protect and manage their own resources, he said.
Examples of mismanagement abound. The number of pirogues in six northwest African countries exploded from 3,000 to 19,000 in the last half-century, but Senegal and other nations have only recently begun to license them.
Guinea-Bissau, a nation of 1.4 million people, is a prime example of how not to run a fishery. According to Vladimir Kacyznski, a marine scientist with the University of Washington, no one has comprehensively studied the nations coastal waters for at least 20 years.
For two years, Sanji Fati was in charge of enforcing Guinea-Bissaus fishing rules. When he took the job in 2005, he said, his agency did not have a single working patrol boat to monitor hundreds of pirogues and dozens of industrial trawlers, most of them foreign. An estimated 40 percent of fish were caught without licenses or in violation of regulations, and vessel operators routinely lied about their haul. Government observers were mostly illiterate, underpaid and easily bought off.
Mr. Fati tightened enforcement, but said he still felt as if he was waging a one-man war. A few months ago, he left in frustration.
That bleak picture did not stop Guinea-Bissau and the European Union from agreeing last May to allow European boats to fish its waters for shrimp, fish, octopus and tuna. Over the next four years, the agreement will pump $42 million into a government that is months behind in paying salaries and still emerging from civil war.
Daniel Gomes, Guinea-Bissaus 12th fishing minister in eight years, said he had tried to be conservative in how much access to grant foreigners, despite paltry scientific data and severe economic pressures.
Still, asked whether his nation would end up with empty waters, he replied: This prospect is not out of the question. This could happen.