Ultimate dives
Tooni Mahto
Oceans presenter Tooni Mahto describes her top dive experiences from the series, including an ice dive and a free dive with sperm whales.
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Free dive
Sea of Cortez: Tooni's unforgettable and emotional encounter free diving (snorkelling) with some "loving" sperm whales.
Research dive
Indian Ocean - coastal waters: Tooni takes on underwater power tools to extract 300 years of climate data from coral for scientific research.
Ice dive
Arctic Ocean: Tooni enters the "eerie twilight" world of ice at -1 degrees centigrade to collect samples from this underwater ecosystem.
Cave dive
Southern Ocean: An exhausting dive through a system of sea caves tests Tooni's physical and mental resources.
Visit the locations section to find out more on coral coring in the Indian Ocean the sperm whales of San Pedro Martir, examining the pack ice and the sea caves of Waterfall Bay.