The head of Tonga's Fisheries department says it's working to improve enforcement around illegal fishing in an effort to try and conserve stocks.
Vilimo Fakalolo says poor enforcement from fisheries officers and authorities in the past has allowed a decline in fish stocks and other marine life.
Mr Fakalolo says aerial surveillance by the air forces of Australia and New Zealand is vital to their monitoring operations.
He says Tonga with assistance from the Forum Fiheries Agency uses the photo evidence from the surveillance for prosecuting the operators of illegal vessels
The department held a workshop last week to train staff in control and surveillance.
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