Hawaii Marine Life Guide
Remoras
Remoras are unusual ocean fish with a suction disk on top of the head, allowing them to hitch rides on sharks, turtles, rays, whales, dolphins and even boats. In Hawaii, they are called omo and are also known as suckerfishes.
Remoras in Hawaii
Remoras are unusual fish best known for the suction disk on top of their head. This disk works like a natural suction cup, helping the fish attach to larger marine animals and travel through the ocean with less effort.
In Hawaii, remoras are called omo. They are also known as suckerfishes. Remoras may attach to sharks, sea turtles, rays, whales, dolphins, boats, floating objects and even other remoras.
How Remoras Hitch a Ride
A remora's suction disk is a modified fin with ridges that help it grip. The fish can press the disk against a host, hold on while the larger animal swims, then release and reattach when needed.
This hitchhiking lifestyle helps remoras save energy. It also gives them access to food opportunities, such as scraps left behind when a host feeds, small particles in the water or tiny organisms near the host animal.
Do Remoras Harm Their Hosts?
Remoras usually do not harm the animals they attach to. They do not bore into the skin or feed directly on the host's body. Most of the time, they are simply along for the ride.
The Slender Remora is the largest remora species and can grow up to about 3 feet long. If one swims near you while snorkeling or diving, stay calm and let it move naturally. Related pages include the Hawaii fish guide, Hawaii sharks, sea turtles, rays and Oahu shark dive tours.
