Charles Darwin once dismissed the ocean as a ‘tedious waste, a desert of water.’ Some of his contemporaries disagreed. The brave Challenger expedition of the 1870s set out to discover what lurked beneath, traversing over 100,000 kilometres and discovered 4,772 specimens, from sea snails to snake eels, discovered the deepest trench on earth, and toppled false assumptions about the lack of life under the waves. Over a century later, the Census of Marine Life picked up the baton. An eighty-country collaboration, with 2,700 scientists, the project identified another 6,000 species. Yet even these numbers are a literal drop in the ocean.

Oliver Steeds, Ocean Census director and chief executive of Nekton, a UK-based marine science and conservation institute, speaks to Naka Kondo, the lead editor of Back to Blue initiative about a new mission, the Ocean Census, launches this year with a far greater ambition: to find at least 100,000 new marine species in its first decade.