Meet uhu the Parrotfish

  • Terry Lilley / Contributed photo

    A female uhu.

  • Terry Lilley / Contributed photo

    A male uhu.

Uhu is one of the most beautiful fish in the entire Pacific Ocean but they are also one of the most important fish! They eat the old diseased corals and poop out the hard calcium carbonate coral structure that makes much of the sand on our beaches! If it wasn’t for uhu we would not have our beautiful beaches here in Hawaii!

But what is so cool about this fish, that can grow to three feet long, is they are all females when they hatch! The babies are just a drab brown color and swim in large schools across the coral reef eating algae. As they grow they turn into a brown and rust red color. Then something amazing happens.

Some of the female uhu start changing colors and turn bright blue, green, yellow and purple! The females convert to males for the purpose of breeding and spreading their genetics around to keep the female populations strong and healthy. It is up to the females to decide when it is time to convert to males so on some coral reefs there are only females.

But when the reef starts to change the females produce males to go out into other female colonies to breed and produce a stronger generation that can better deal with the changes!

The parrotfish are in the wrasse family and all of these fish species are controlled entirely by female genetics. Their reproduction corresponds with the very reproduction of the coral reef and in Hawaiian history this is represented by the goddess Hina, the goddess of the moon cycle, women and corals.

In the Hawaiian language uhu means diarrhea! This is because when the uhu eat the coral they are always pooping out the hard coral structure to digest the soft coral polyps. So in Hawaii if you are enjoying a beautiful evening on the white sandy beach you are sitting on uhu poop!

For some amazing underwater movies of our Hawaiian parrotfish visit the educational web To be involved in a marine science educational nonprofit visit


Terry Lilley, marine biologist, is a Hanalei resident. His websites include,

  1. paulot May 19, 2019 3:44 pm Reply

    Another fine article from (or sometimes about) Terry Lilley. We are darn lucky to have him in our midst and in our waters. I’ve never met him but appreciate his dedication and knowledge.

    It wasn’t so long ago that he was accused of “claiming” to be a marine biologists from those who preferred not to care about the information he provides us.

    Mahalos to Terry Lilley

  2. Kauaidoug May 20, 2019 7:54 am Reply

    Interesting , informative, relevant well written, and keep them coming. Mahalo!

  3. Napua Casson May 22, 2019 11:07 am Reply

    Please provide your source for your uhu definition. Uhu is not defined as “diarrhea” in any of the Hawaiian language dictionaries online at nor is it in the printed dictionary. If you cannot provide a reputable source using your definition printed in this article, Iʻd strongly advise you to edit it appropriately.

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