I've seen hundreds of sharks in my day, but not in Hawai'i. Most of them have been at Palmyra Atoll, which is a thousand miles south of Hawai'i and in the middle of nowhere.

At Palmyra, there are still lots of big fish eating smaller fish all the way up the food chain. Sharks are about the biggest. This is called an apex predator-dominated system, which means the big fish are still there and the marine ecosystem is healthy.

The first time I went diving at Palmyra, I plopped overboard and immediately saw six sharks gliding by, 20 feet away. On that dive alone, I counted about 50 sharks in as many minutes. Sometimes they'd come close and I'd stare them down. Big snappers would also swim by.

With Earth Day's 40th anniversary today, I find myself thinking about the ocean and how I never saw sharks while growing up in Hawai'i. Well, once when I was 12, my dad, my brothers and I were spear fishing in Kona. Suddenly, my dad shouted from afar for us to swim slowly away because he was surrounded by sharks.

My oldest brother jumped into the rowboat, pulling hard on the oars to rescue my dad. I had recently bought a Plexiglas housing for my Instamatic camera and shouted, "Wait! I want to take pictures!" My brother rolled his eyes and ordered me ashore. My dad made it back, but the story always gave us kids a little tingle every time it was told.

Anyone who dives in the main Hawaiian Islands will tell you that my dad's rare brush with sharks four decades ago is rarer still today, especially when compared to a place like Palmyra.

We humans fear sharks, and in our efforts to control our surroundings, we have eliminated most of the predators that can cause us harm. In the process, we have begun to unravel the very web of life that sustains us.

There are fewer and fewer big fish in Hawai'i. Though we feel somehow safer, it's a surface safety. Underneath, important pieces of our ocean are missing. We need to give the ocean and reefs a rest.

Our oceans and reefs are incredible biological, economic and cultural resources, but they are not without limits. In Hawai'i and the world over, there are serious threats to our oceans — pollution, invasive species, overfishing, marine debris and climate change. One result in the main Hawaiian Islands is a precipitous 75 percent decline in nearshore fisheries over the past century.

So it's encouraging to see that the Legislature is poised to strengthen prohibitions in Hawai'i on the possession and sale of shark fins to help curtail the cruel and unsustainable practice of shark finning in our world's oceans.

The good news is that coral reefs and many marine creatures are resilient. If we reconsider how we use the ocean and act now, we can still protect this priceless natural asset.

When you go fishing, for example, don't always go for the biggest fish — they are the ones who make the most eggs to replenish our reefs. And take only what you need to fill your table, not your freezer. You can influence how much plastic makes its way into the oceans by using reusable shopping bags and water bottles. You can limit pollution into the ocean by forgoing chemical fertilizers and using organic compost.

Finally, treat yourself and your family to a night at the movies. Opening in theaters across the state today is Disneynature's new film, "Oceans" — a spectacular look at the world's sea creatures. It's for a good cause: For each ticket sold during the first week, a contribution will be made to The Nature Conservancy's global marine program.

Just as important, you're sure to see a lot of sharks — and learn how to protect our oceans for generations to come.