The International Commission for the Conservation of Atlantic Tunas decided to replace a largely paper-based catch-recording system, the BBC reported.
The Pew Environment Group said in a report last month 140 percent more bluefin meat entered the market from the Mediterranean than had been declared, largely because of abuses of the paper-based system.
"ICCAT's new bluefin tuna electronic catch-documentation scheme is an important and positive leap forwards in the monitoring of the fishery and protection of the species," said Sergi Tudela, head of fisheries for World Wildlife Fund in the Mediterranean region.
But the new system will track not bluefin through farms or "ranches," where they are fattened for eventual sale, usually to Japan.
"The continued absence of data on quantity and size of bluefin tuna caged in fattening farms creates a black hole and provides an easy facility for the laundering of illegal, unregulated and unreported catches of Mediterranean bluefin tuna," Tudela said.
Silky sharks, often caught accidentally by tuna boats, also received more protection, as fishermen will now have to release them alive.
Government delegates at an ICCAT meeting in Istanbul, Turkey, also approved a minimum legal size for swordfish catches.