Hawai‘i is a special group of islands because we are in the middle of the sea and lack barrier reefs. Our islands are relatively new compared to other island chains in the Pacific, like the Philippines, and we have huge waves that break on our lava reefs on a regular basis.
Due to the large surf, constant wind and ocean currents, our fish species have evolved differently than in the rest of the Pacific Ocean.
While Hawaiian people learned to surf waves over a hundred years ago, Hawaiian fish also learned to surf waves. The human surfers ride on top of the wave and the fish schools ride the underside of the wave, and sometimes they all ride the same wave. I have been a surfer all my life, so while diving I feel comfortable shooting underwater movies right under waves we surf on to see what the fish are doing, and I captured some remarkable footage of fish surfing.
The Hawaiian reef is always a battleground for space between limu (algae) and coral growth. Each species wants its own space to grow on the reef. The algae-eating fish, like the manini (convict tangs), keep the reef in balance so the algae does not take over and the coral does not cover the entire reef.
The large schools of manini, along with the api (whitespotted surgeonfish) and maikoiko the whitebar surgeonfish, have learned to surf the underside of the waves. When the wave ends, the fish drop down and feed on the algae on the reef for just a few seconds, then they ride the surge of the wave back out to sea. While waiting for the next wave to come in they feed on the algae on the outer reef, then ride the next wave toward shore to feed again on the inside reef.
We all know that the waves are different sizes every day, so this causes the schools of algae-eating fish to ride different waves and feed on different parts of the reef every day, which keeps them from over feeding on any one part of the reef. This balance gives plenty of good limu for the honu (sea turtles) to feed on, and also healthy coral for the butterfly fish and uhu (parrotfish) to feed on.
Surfing a wave is all about understanding balance, if you are a human on top of the wave or a fish riding the underside of the wave. You can see the surfing schools of fish in action in my documentary movie about marine life at Sharks Cove on O‘ahu up on my marine life educational webpage at underwater2web.com and YouTube at Underwater2web.
All of my movies are made for the whole family to watch, and are good to show in the classroom for marine life education.
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Terry Lilley is a marine biologist living in Hanalei. He is co-founder of Reef Guardians Hawai‘i, a nonprofit on a mission to provide education and resources to protect the coral reef. To donate to Reef Guardians Hawai‘i go to www.reefguardianshawaii.org.
