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Oarfish

life science Maturity 5-7 Next article →

The oarfish is a very long and unusual fish. It belongs to a small family called Regalecidae. This name comes from the Latin word regalis, which means royal.

Giant Oarfish
Giant Oarfish

The giant oarfish is the longest bony fish living today. It can grow to a huge size. These fish live in the deep, open ocean. They stay in layers of water between 250 and 1,000 meters deep. Because they live so deep, humans rarely see them alive.

Oarfish move through the water in a special way. They use a long fin on their backs called a dorsal fin. This fin starts above their eyes and runs the whole length of their body. They swim using amiiform swimming, which means they move the fin in wavy motions. This keeps their long bodies quite straight.

Regalecus glesne juvenile
Regalecus glesne juvenile

They do not have a swim bladder to help them stay at one depth. Instead, they likely use their tail movements to stay where they want to be. They also have long fins on their bellies.

People have been curious about these fish for a long time. Scientists first described the oarfish back in 1772. Because they are so long and rare, people once thought they were sea serpents.

Giant oarfish bermuda beach 1860
Giant oarfish bermuda beach 1860

In Japan, some call them the Messenger from the Sea God's Palace. Some people believe they appear before big earthquakes or tsunamis happen. However, a study from 2019 says this link is just an illusion. The fish are simply appearing by chance.

There are three different species of oarfish in the world. One is the giant oarfish, or Regalecus glesne. Another is the streamer fish, known as Agrostichthys parkeri. The third is Russell's oarfish, or Regalecus russelii.

Giant Oarfish
Giant Oarfish

The giant oarfish is much larger than the others. The streamer fish is also quite long. All these fish are silver with small dark spots on their skin. They have no scales on their bodies.

Oarfish eat many different things in the ocean. They mostly eat zooplankton, which are tiny living things. They also eat small shrimp, jellyfish, and squid. They use suction to pull this food into their mouths.

Regalecus glesne juvenile
Regalecus glesne juvenile

To stay safe, they can use a trick called autotomy. This is when they drop their own tail to get away from a predator. The wound will heal, but the tail does not grow back. This helps them survive even when they are in danger.

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🖼️ Images & Media (3)
File:Giant Oarfish.jpg
Giant Oarfish.jpg
File:Regalecus glesne juvenile.png
Regalecus glesne juvenile.png
File:Giant oarfish bermuda beach 1860.jpg
Giant oarfish bermuda beach 1860.jpg
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