Remove the predators, and the whole ecosystem begins to crash like a house of cards. As the sharks disappear, the predator-prey balance dramatically shifts, and the health of our oceans declines.
New England waters are some of my favorite - they are some of the richest waters because they are temperate waters and nutrient-rich, and therefore provide food for so many animals, from giant whales to sharks to everything else.
I think that going to the beach as a child, being in the water and smelling that salt air and hearing the seagulls, it had a real calming effect. But also, it was a mysterious thing - I remember wondering what was under those dark New England seas.
I swam with my first shark in the 1980s. I was 20 miles off the coast of Rhode Island, working with a group of marine scientists. Late in the day, a 5-foot long blue shark swam into our chum slick. For the next hour, I marveled at the animal's stunning indigo color and the elegant way she moved effortlessly through the sea.
Under the snowcapped mountains of Fiordland National Park, freshwater streams empty into the saltwater fiords, creating a unique ecosystem. This is a heavily wooded park, so the water in the streams is stained with tannin, a substance found in plants that makes clean water seem dirty, though it isn't.
I have photographed sharks in waters around the globe, and I always want more and yearn to peer deeper into their world. To feed my passion and to raise awareness, I developed a story about sharks for 'National Geographic' magazine.
