France, March 27 -- For decades, vast areas of ocean beyond national borders have been governed by weak and fragmented rules. These waters - known as the high seas - cover nearly half the planet and support rich but fragile ecosystems.

That changed in January, when the High Seas Treaty - also known as the Biodiversity Beyond National Jurisdiction or BBNJ Agreement - came into force, creating the first global legal framework to protect marine life in international waters.

One of its main tools is the creation of marine protected areas - zones where human activity can be limited or banned so ecosystems can recover. Countries have set a target of protecting 30 percent of the ocean to tackle biodiversity loss.

But while the treaty is ...