Why is it that scuba divers and surfers are some of the strongest advocates of ocean conservation? Because they've spent time in and around the ocean, and they've personally seen the beauty, the fragility, and even the degradation of our planet's blue heart.

Every time I slip into the ocean, it's like going home.

The oxygen cycle, the nitrogen cycle, the carbon cycle, the water cycle - all of these are linked to the existence of life in the sea.

If the sea is sick, we'll feel it. If it dies, we die. Our future and the state of the oceans are one.

Many of us ask what can I, as one person, do, but history shows us that everything good and bad starts because somebody does something or does not do something.

When I first ventured into the Gulf of Mexico in the 1950s, the sea appeared to be a blue infinity too large, too wild to be harmed by anything that people could do.

The value of sharks' lives is now widely understood to be more important than their value as products. And when you have sharks in an area, it's a sign of good health. They're top predators, which means they feed on old, sick, and slower fish, keeping an entire population healthy.