Oarfish - Oceana

Ocean Fishes

Oarfish

Regalecus glesne

Distribution

Worldwide in tropical to warm temperate latitudes

ecosystem/habitat

Mid-water column in the open ocean to depths of at least 3300 feet (1000 m)

Feeding Habits

Filter feeder

Taxonomy

Order Lampridiformes (ribbonfishes and relatives), Family Regalecidae (oarfishes)

 

While that may seem quite heavy, it is not very much for a fish that may reach lengths longer than a school bus. As a result of this general shape and the bright, silvery coloration and long, red fins, some people around the world know the oarfish as the ribbonfish. The first few elements of the dorsal fin are long and wispy, resembling a crown, and give rise to yet another common name for this species, the King of Herrings. Oarfish have very large eyes that they use to see in the extremely low light conditions of the deep parts of the open ocean, their preferred habitat. They rarely come to the ocean surface, perhaps only when dying or disoriented, and occasionally wash up on beaches around their home range (all tropical to warm temperate seas). Most individuals that are discovered near the surface or near beaches do not survive. Unlike most fishes, the oarfish’s body has no scales.

Oarfish are likely the source of sea serpent myths that are part of most maritime cultures around the world. Some observers report that oarfish discovered at the sea surface often swim with their head and ornate “crown” out of the water as if they are searching for something. This curious behavior, the long snake-like body, and the relative rarity with which they are observed at the sea surface (most notably after large storms) all feed the belief that mythical sea serpents attack mariners or even entire ships in the open ocean. However, oarfish are quite harmless. They have very small mouths and no teeth, and they feed by filtering small prey from the water, swimming with their mouths open and capturing their food with modified bones that support their gills.

Though the oarfish is assumed to be naturally rare, the difficulty of studying it in its preferred natural habitat (the deep, mostly dark water column) has prevented scientists from assessing its conservation status or the likelihood that it may become threatened with extinction.

Engage Youth with Sailors for the Sea

Oceana joined forces with Sailors for the Sea, an ocean conservation organization dedicated to educating and engaging the world’s boating community. Sailors for the Sea developed the KELP (Kids Environmental Lesson Plans) program to create the next generation of ocean stewards. Click here or below to download hands-on marine science activities for kids.

Kids Environmental Lesson Plans

Additional Resources:

Florida Museum of Natural History