脆弱天堂 20

There are 150 tonnes of fish in this one haul.

It used to take a fishing vessel one whole year to catch this many fish.

These are mostly yellowfin tuna, plus some skipjack.

As they're slower breeders than skipjack

Many yellowfin are caught before they're old enough to breed.

This makes them more vulnerable to over-fishing.

Tuna fishing has grown into an 8-billion-dollar industry.

And over 4 million tonnes of tuna are caught worldwide each year

A four-fold increase in as many decades.

Almost 2/3 of the catch now comes from the Pacific.

In the Atlantic, yellowfin catches have been shrinking since 1990.

Now a similar decline has begun in the Pacific.

Tuna need to swim constantly to keep water flowing over their gills

Otherwise they can't breathe.

The fishermen want to get them out of the water as quickly as possible.

When starved of oxygen, a build-up of lactic acid in their muscles

causes the quality of their meat to deteriorate.