The entire production cycle of "Blue Planet II" lasted four years, and most of the time was spent in the preliminary planning and preparation with related professional scientists. In order to shoot this 7-episode documentary, the BBC Natural History Department conducted 125 expeditions, visited 39 countries, and covered almost all the waters of the world's five oceans, including the 1,000-meter-deep seabed under the Antarctic ice sheet
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Before the shooting, the team spent a year of research and preparation, cooperated with dozens of marine scientists and talked with a large number of sailing crews and fishermen. When encountering ocean currents and tides, low visibility or sudden changes in weather, the team will promptly seek help from locals
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The ronin trevally preying on seabirds was originally a story passed down by South African fishermen. No image data has ever confirmed it. The filming team also resolutely carried an 800-jin heavy machine to squat to shoot. It's not that every shot can meet expectations, and it may take a little bit of luck. The filming team experienced a lot of ups and downs when filming the leather scales. The leather scales usually lay eggs once a year, which lasts about an hour. The team spent two years investigating and defending. The first year failed and the second year continued. After monitoring for more than hundreds of hours, I finally waited for the amazing time when the leather scales lay eggs
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