The more I scuba dive in Kauai, the more I realize how little we know about our fish populations. Native Hawaiians knew more about their marine fish then any culture I have ever studied because they needed this knowledge to survive on a small isolated island and feed their community. Many of the fish species even have different names for different age groups of fish like the young ulua is called a papio.
Several hundred years ago the Hawaiians did not have snorkel mask for observing tiny baby fish and they did not have the use of DNA to figure out which species are related to each other. They also did not have satellites for tracking ocean currents from space! Even with all of these new scientific tools we still don’t know where most fish breed and where their eggs hatch.
The Queen Nenue is a bright yellow fish that is normally a grey colored chub. Chubs are one of the most common fish in our nearshore environment and everyone who has gone in the water to snorkel or dive here in Kauai have seen many of these fish. They are often caught by the locals as food.
As a marine biologist, I wanted to know why certain chubs are bright yellow. This yellow phase is quite rare and I have seen six of these fish in Kauai and over 6,000 of the grey chubs. Where does this yellow fish come from?
I have asked dozens of native Hawaiian fishermen that question and no one seems to know. Matter of fact, no one has ever seen a baby chub at all so we don’t know whether the yellow chubs are hatched out yellow or were they grey and then turned yellow as they grew to adult. We have a lot of adult chubs in Kauai so there must be babies somewhere.
The lack of finding any baby chubs on our nearshore reefs is quite the mystery. The mid-size chubs just seem to appear out of nowhere and all of the yellow phase chubs I have seen have been adults.
Maybe the chubs are similar to our honu, where the babies go way out to sea to live the first part of their life and then come back to shore when they are half grown. Maybe the chubs go down into deep water to reproduce and the babies stay in the deep water until they are adults.
We have recently found millions of baby fish floating around in sea surface currents called sea slicks. Do baby nenue float around in surface currents until they grow older, then swim back to the nearshore reefs? If anyone out there has ever seen a baby chub or know where they live, please let me know!
If I am ever going to find out where the Queen Nenue comes from, then I have to fist find a baby nenue to start with, and after 2,000 dives here in Kauai I have yet to find one.
The life cycle of many of our fish species is still poorly understood and we need to start tracking these fish with critter cameras and other scientific tools to better understand where they live and reproduce.
We can’t begin to protect our coral reefs and marine life if we don’t even know where each species lives. That would be like trying to save our rare native Koloa duck without ever seeing a baby or even know where they nests. The sea around us is still less observed than the surface of the moon and you may well be the first one to find a baby chub on your next dive.
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Terry Lilley is a marine biologist living in Hanalei Kaua‘i 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 reefguardians.org
