The High Seas Treaty reached a major milestone last week after more than 60 countries ratified the agreement, passing a key threshold that sets the stage for new conservation of international waters. But Canada has yet to formally approve the treaty. Until it does, the country with the longest coastline in the world will have limited opportunities to participate in treaty processes, including environmental assessments and efforts to establish marine protected areas in international waters. The High Seas Treaty is the first international agreement aimed at conserving and ensuring sustainable use of biodiversity in marine areas that fall outside any single country’s jurisdiction — an area covering about two-thirds of the open ocean. After nearly two decades of negotiations, the treaty establishes new tools to create marine protected areas in international waters, a crucial step for meeting the global commitment to conserve 30 per cent of land and waters by 2030. It also lays out legally binding rules to strengthen scientific cooperation and ensure the benefits derived from marine biodiversity used for food, pharmaceuticals, cosmetics and more are shared fairly. The High Seas Treaty is the first international agreement aimed at conserving biodiversity in marine areas outside national jurisdiction. That includes areas like the Sargasso Sea, a unique sea bounded not by land but by four Atlantic Ocean currents, where this octopus was photographed. Photo: Shane Gross “It’s a historic milestone to have this kind of law in place,” Stephanie Hewson, a staff lawyer focused on marine conservation with the non-profit West Coast Environmental Law, said in an interview. While a patchwork of international rules govern specific activities like shipping and fishing, this is the first treaty to look holistically at marine biodiversity in the high seas. Covering almost 70 per cent of the planet, the high seas include biodiversity hot spots like Saya de Malha Bank, an enormous seagrass community found in the Indian Ocean between the Seychelles and Mauritius, and the Costa Rica Thermal Dome, which offers ideal conditions for an immense bloom of microscopic blue-green algae. That algae forms the base of a rich food web that supports blue whales, dolphins, sea turtles, sharks and rays. Until it ratifies, Canada won’t be part of environmental assessments, decisions around marine protected areas Canada signed onto the treaty in March 2024, touting its importance for meeting international conservation targets that 196 countries committed to under the global biodiversity framework, which Canadian officials helped broker in Montreal almost three years ago. “We simply cannot get there without a treaty to protect our high seas beyond national jurisdiction,” Steven Guilbeault, then-minister of Environment and Climate Change Canada, said in a statement at the time. Canada’s signature signalled its support, but the country won’t be able to fully participate in treaty processes until it ratifies the agreement. In Canada, ratification involves tabling the treaty in the House of Commons for 21 days to give members of Parliament an opportunity to consider the agreement — but the final decision rests with cabinet. While Hewson said as far as she knows the federal government still intends to ratify the treaty, which she called “great news,” she warned “it’s not ratified, till it’s ratified.” “Canada has been instrumental in moving this treaty forward,” she said. But, she added, its ability to lead or even participate in the development of treaty processes and institutions moving forward will be limited until it ratifies. It also means Canada wouldn’t be part of decisions about where and how to establish marine protected areas in the high seas and limited in its participation in environmental impact assessments of planned activities that could harm biodiversity — even if they’re just outside the country’s waters, Hewson warned. While countries that have not ratified the treaty will still be able to provide comments to be considered during environmental impact assessments, parties to the treaty have additional opportunities to participate in the processes. Global Affairs Canada and Fisheries and Oceans Canada did not respond to The Narwhal’s request for comment by publication time. Ratification milestone celebrated, but more work remains before treaty can benefit ailing seas The timeline for Canada’s ratification remains unclear. Regardless, Hewson said it was an exciting moment when the treaty secured the 60 state ratifications required for it to become international law. United Nations Secretary-General António Guterres called it “a historic achievement for the ocean and for multilateralism.” “As we confront the triple planetary crisis of climate change, biodiversity loss and pollution, this agreement is a lifeline for the ocean and humanity,” he said in a statement. The milestone came just days before the Potsdam Institute for Climate Impact Research released its second annual Planetary Health Check report, which warned “the world’s oceans are acidifying to an unsafe degree.” Alongside acidification, plastic pollution is a major threat to ocean health and biodiversity. Every year, huge numbers of marine creatures are killed or injured when they ingest plastic waste or become entangled in it. Photo: Shane Gross Oceans are a major carbon sink. By capturing significant amounts of carbon dioxide every year they play a crucial role in moderating climate change driven by humanity’s excessive burning of fossil fuels. But absorbing such large amounts of carbon dioxide has caused the oceans to become more acidic, threatening species and undermining vital marine habitats and food webs. Rebecca Hubbard, the director of the High Seas Alliance of more than 70 civil society groups advocating for a strong treaty, celebrated passing the ratification threshold, but cautioned it’s “not the finish line.” “The treaty’s true strength lies in universal participation,” she said in a statement, urging all remaining nations to ratify the agreement. Like Canada, the United States, China, the United Kingdom and Australia have all signed but not yet ratified the agreement. Neither Russia nor Japan have signed. In the meantime, work is underway to build the institutions and processes for implementing the treaty. Proposals are also being developed for marine protected areas to conserve the biodiversity hot spots, including the Sargasso Sea, an area bounded by four Atlantic Ocean currents known for its floating masses of seaweed that offer rich habitat for a range of species. Recent Posts Is mining ‘still the one’ in northern Ontario? A past effort to attract fan tourism to Shania Twain’s hometown of Timmins didn’t go… Dozens of nations move to safeguard international waters, but not Canada — yet Sept. 26, 2025 5 min. read Canada played an ‘instrumental’ role in the High Seas Treaty, but until it ratifies the… Sleepless nights, toxic smoke: life beside Canada’s first LNG export plant By Matt Simmons (Local Journalism Initiative Reporter) Sept. 26, 2025 9 min. read Residents of Kitimat, B.C., say LNG Canada’s operations are leaving them exhausted and worried for…
Dozens of nations move to safeguard international waters, but not Canada yet
