CRITTER: Meet the Hawaiian fish that rides waves

Hawai‘i has a very-unique marine ecosystem because of the large waves that break directly onto nearshore reefs. As far as islands go, Hawai‘i is a new island chain, and on Hawai‘i Island new land is added to the sea every few years from the erupting volcanoes.

Hawai‘i has not been above the sea surface for long enough to have fringing coral reefs grow like we see in Tahiti, Fiji, Palau and the Philippines. Islands with outer barrier coral reefs have large, calm lagoons with lots of coral growth, and the fish that live there do not have to deal with waves that pound their home daily!

Maikoiko the Hawaiian white-bar surgeon-fish has adapted to coral reefs by learning to surf under the waves! This 10-inch-long fish lives in large schools of 50 to 100 in shallow water right in the surf zone. When a wave comes the school of fish will ride the wave toward shore.

When the wave stops the fish feed on algae growing on the reef. When the surge created from the wave goes back out to sea the fish ride that and then pause to feed on algae until the next wave comes. This type of feeding activity is like when we mow our lawn. We go one direction, turn around and go back the other direction until the entire lawn has been mowed. Maikoiko does the same thing by riding waves and eating the algae on different parts of the reef where the wave takes them.

The white-bar surgeon-fish is a super important species for the health of our corals because they clean the reef of algae, and that makes room for the corals to grow. Maikoiko often schools with other fish like the convict tang and other surgeon-fish species, and that makes a much-larger school of fish to ride the waves and clean the reef.

Maikoiko is in the surgeonfish family because it has a razor-sharp spine at the base of its tail that they use for protection from predators and us humans who catch fish. The Hawaiian name refers to a type of sugar cane that blows in the wind and looks like a school of fish underwater riding a wave.

You can see mailoiko in action on my underwater educational web page in my movie “The World’s Guide To Hawaiian Reef Fish” at www.underwater2web.com and also see many of my Hawaiian underwater and surf movies up on my YouTube at Underwater2web.

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Terry Lilley is a marine biologist living in Hanalei, and 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.