A researcher from the Australian National University has been recognised internationally for her work that could reshape how the world protects its oceans.

Associate Professor Ana Sequeira has been named Australia’s National Champion in the Frontiers Planet Prize, placing her among 25 leading scientists worldwide addressing urgent environmental challenges.

Her study, published in Science, is one of the global efforts to understand how marine megafauna use the ocean. It involved nearly 400 researchers and combined satellite tracking data from more than 100 species, including whales, sharks, turtles and seabirds.

The research identifies key areas used by these species for feeding, breeding and migration, providing a clearer picture of where conservation efforts could be most effective.

What excites Sequeira the most is that there is now a “clear, science-based roadmap capable of changing the trajectory of global marine biodiversity conservation”.

Findings reveal many critical habitats lie outside existing protected areas, exposing gaps in current conservation strategies.

The study comes at a time when about a third of these species are threatened with extinction despite their vital role in maintaining ocean health.

It is expected to inform major international policy decisions, including implementation of the High Seas Treaty and Australia’s High Seas Act, by identifying shared “hotspots” where protections could have the greatest impact.

The research also supports a new international policy report developed with the United Nations University Centre for Policy Research and the Potsdam Institute for Climate Impact Research, outlining strategies to tackle interconnected environmental crises.

Recommendations include expanding marine protected areas, incorporating key habitats into national ocean planning, and strengthening protections for migratory species.

The Frontiers Planet Prize is the world’s largest science competition focused on planetary health, awarding three international champions $US1 million ($A1.4 million) each to scale up their research.

Associate Professor Sequeira will now advance to the final stage of the competition, with global winners to be announced later this year.