Paki‘i is one very strange fish! The Hawaiian name means fallen flat or spread out because they lay flat on the sandy seafloor or flat reef areas.
Paki‘i is one very strange fish! The Hawaiian name means fallen flat or spread out because they lay flat on the sandy seafloor or flat reef areas.
The Peacock Flounder is so hard to see that most divers and snorkelers go right over them because they are so camouflaged and they can change colors instantly to whatever background reef they are on. The Peacock Flounder is the largest species in Hawai‘i and they can grow up to 20 inches long but they are related to the giant halibut on the U.S. West Coast that can get seven foot long!
Anyone who has seen this strange fish will notice that it has two eyes on top of its head and lays flat on its white belly on the seafloor. Recently at Sharks Cove in O‘ahu, I shot video of a large paki‘i in two feet deep of water where it did not move for an hour. Dozens of snorkelers swam right over it and never saw it. The flounder is an ambush predator as its prey also can’t see it. When a small fish swims over the top of the paki‘i it zooms up and sucks down the prey. This happens so fast that the prey has no idea what just ate them.
What is so odd about the flatfish family which includes the halibut, sole and flounder is they start out looking just like a normal fish when they hatch. They have an eye on each side of their head and a normal looking dorsal and pectoral fin. As they grow one eye migrates to the top of the head and they turn sideways. They start to develop a white underside and eventually lay flat on the seafloor with both eyes on top of their head.
Some flounder species have their right eye migrate and others have their left eye migrate. They call this a “right eyed flounder” or a “left eyed flounder”. The Peacock Flounder is a left eyed flatfish. Here in Hawai‘i we have about 12 left eyed flounder species and only one right eyed species. The Peacock Flounder is the largest left eyed species and is the most common nearshore species.
Paki‘i can rotate each eye independently much like a chameleon can on land and they often bury under the sand with only their eyes poking up like a submarine periscope. This makes them even harder to see. When they move from the flat reef where they have a blocked pattern to the sand they immediately develop a sandy pattern to match their background. They can change colors in less than a second!
The male paki‘i have their eyes set wider on their head than the females and the males have a pectoral fin that is now on their back that they raise when they swim fast or use to show off to a female for mating.
You can see paki‘i in action up on my underwater educational web page at www.underwater2web or my YouTube movie channel at Underwater2web.
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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 Hawaii go to www.reefguardianshawaii.org.
Terry’s articles are my favorite feature of TGI. Most of the Paki’i (flounders) I have seen were in the calm sandy bay of Salt Pond Beach Park, while teaching my grandkids to snorkel. This is also where we’ve seen Flying Gurnards, which is another strange and very cool fish. After many years of diving here, I hadn’t realized such an “ordinary” looking place like Salt Pond could contain so much interesting sea life. We’ve also seen Lionfish, monk seals, Eagle Rays, and even a 6 foot reef shark on one occasion!