The fishermen's workday starts in the early hours. 

"We cast off every day praying we'll find some fish," says Eduino Quadros, the boat's captain.

The boat has no fish-locating equipment on board. Instead, the tuna fishermen scan the ocean's surface with binoculars for hours. There are more than 30 boats like Captain Quadros' on the waters around the nine islands of the Azores, a Portuguese archipelago in the Atlantic. 

Competition here is fierce to catch enough fish before reaching the quota, and no more may be taken.

Seagulls are the sign the fishermen have been waiting for. A school of tuna is chasing the small fish below and driving them to the surface. Above, the seagulls are feeding.

Now, they will use live bait to attract the tuna.

Water spurts out of the boat to excite the fish and start them biting.

"They're biting! Throw more bait!" says fisherman Paulo Quadros. 

Quadros is the captain's brother and co-owner of the fishing boat they inherited from their father. 

Fishing has been sustainable for generations here. Off the Azores, tuna may only be caught with a fishing rod, and only those weighing more than 10 kilograms (22 pounds) may be kept. Nets are forbidden.

There are 15 men on board, with 15 families to feed.

Then came the big shock: The fishing authority announced a moratorium on bigeye tuna, effective midnight tonight.

Captain Eduino and his brother Paolo are angry.

"It's frustrating. We've been fishing for less than a month, and now we must stop," says Paulo Quadras.

Captain Eduino Quadros is disappointed, he says. "I hate to say it, but the situation now is much worse than when I started."

They are on the verge of giving up, as many others already have.

The sun slowly sets, bringing this year's bigeye tuna fishing to an end.

Captain Eduino asks at the cannery if he can unload his catch. Not for two days, he is told, because the freezers are full. Yet another setback.

On the way back to port, he shows us who empties the seas. Purse seine nets. 

"Purse seine nets should be outlawed. They kill entire schools, especially the way they're used today. They float decoy shoals on the surface. The young fish shelter under them for protection from predators, but in the end, they die in the nets."

The nets are two kilometers long and 200 meters deep. Almost 70% of the year's fish are caught this way. The main European culprits are the Spanish and French fleets.

If they don't want a lot of species to die out, they should ban it, says Captain Quadros. 

Two days later, the fishermen can finally unload their catch.

The magnificent fish, weighing 70 or 80 kilograms, are in great demand at international markets. They are ideal for sushi or as steaks in gourmet restaurants and should be a safe bet. But the buyer brings the next disappointment.

Only €2 per kilo for the premium fish. The fish plant dictates the price. 

The authority had promised the fishers a deal: lower catch volumes with higher purchase prices.

"But that didn't happen. They didn't even honor the price! What's wrong with our government? They're in charge, so why don't they do something? Isn't that what we pay them for?" Captain Quadros says. 

This could spell the end of the fleet. Around 2,000 jobs are directly and indirectly dependent on fishing. 

Almost 240,000 people live on the Azores, but more and more are leaving the islands, including the fishers' children. 

Finding workers is another problem, says another fishing boat captain as he unloads his catch.

"If this isn't the end, we're very close to it. The quota is too low, the fish prices are low, fuel is very expensive ... It's bad for us. I can't look my men in the eye on the boat. It makes me sick," Captain Afonso says.