If this video does not work, try other source from the menu or open it from the alternative links below.
Blue Planet II: Season 1, Episode 4
1 - 4: Big Blue
Survival in the remote open oceans is tough and baby turtles use debris as rafts to stay afloat while the Portuguese man-of-war sail along hunting for fish. There's also footage of the "boiling sea" effect created by lanternfish being trapped on the surface of the water by predators.