http://www.bbc.co.uk/news/science-environment-14066250Too many boats chasing too few fish means canned tuna might become a delicacy
Two more species of tuna have been added to the Red List of Threatened Species.
They join the Southern bluefin tuna - listed as critically endangered.
The report, published in this week's Science, is the first global assessment of this highly prized family of fish, which are at risk of being over-fished.
The World Conservation Union (IUCN) says there is a lack of resolve to protect against overexploitation driven by high prices.
Until this latest study, attempts to assess the health of scombrid and billfish populations, families of fish that include tuna and swordfish, have been carried out at a regional scale.