Guarding the Only Sea on Earth With No Coastline

The Sargasso Sea is the only sea on the planet defined by currents rather than coastlines: some two million square miles of the subtropical North Atlantic held in place by the gyre, where rafts of floating sargassum weed form a nursery and feeding ground for turtles, billfish and juvenile eels. It is also the only known spawning ground for two endangered species of anguillid eel, and it lies almost entirely on the high seas, where no single government could protect it. Led by Bermuda, the Sargasso Sea Commission was created under the 2014 Hamilton Declaration, a voluntary agreement now backed by governments including the United States and United Kingdom, making it the first serious attempt to steward a high seas ecosystem using existing international law. The Commission has since published the first Socio-Ecosystem Diagnostic Analysis for a high seas area, drawing on more than 25 experts over four years, and the arrival of the High Seas Treaty gives its case for a formal high seas marine protected area a legal route at last.