The oarfish, a deep-sea creature rarely seen by humans, has long been associated with mystery and folklore due to its elongated, serpent-like appearance. This article explores its true characteristics, why it occasionally appears in shallower waters, and addresses misconceptions about its threat to people.
What Oarfish Are
Oarfish are large, elongated pelagic fish belonging to the family Regalecidae, inhabiting temperate and tropical ocean zones. The giant oarfish (Regalecus glesne) is the world’s longest bony fish, reaching lengths of up to 8 meters (26 feet), with unconfirmed reports of 11 meters (36 feet) or more. They possess a distinctive ribbon-like body, silvery or silvery-blue skin, and a prominent reddish or pink dorsal fin that runs their entire length. This fin undulates to propel the fish, while their bodies remain relatively straight.
These deep-sea dwellers typically inhabit the mesopelagic zone, found at depths of 200 to 1,000 meters (656 to 3,280 feet), though some have been observed as shallow as 15 meters. Their elusive nature means live observations in their natural habitat are rare; the first deep-sea footage was recorded in 2008. Oarfish lack scales and visible teeth, and their mouths are small and protrusible.
Are Oarfish Dangerous to People?
Despite their imposing size and snake-like appearance, oarfish are not dangerous to humans. They are filter feeders, primarily consuming zooplankton, krill, and other small crustaceans, which they strain using specialized gill rakers. Their diet also includes small fish, jellyfish, and squid. The absence of large teeth or aggressive tendencies means they pose no physical threat to people.
No documented cases exist of oarfish attacking humans. When encountered, their behavior is passive and reclusive, instinctively avoiding confrontation. Any perceived danger stems from their unusual appearance and associated myths. Their gelatinous flesh is not palatable for human consumption, so they are not commercially fished.
Why Oarfish Come to the Surface
Oarfish are deep-sea creatures; their appearance at the surface or washing ashore is uncommon and often indicates distress. Several theories explain why these fish surface. They may be ill, injured, or disoriented, unable to maintain their deep-water habitat. Ocean currents can also push them towards shallower waters, where they struggle due to changes in pressure and temperature.
A persistent myth links oarfish sightings to impending natural disasters like earthquakes or tsunamis. This belief, prevalent in Japanese folklore as “Ryugu no Tsukai” (“messenger from the sea god’s palace”), gained traction after multiple oarfish washed ashore before the 2011 Tohoku earthquake and tsunami. However, scientific evidence does not support a correlation between oarfish surfacing and seismic activity. A 2019 study found no statistically significant link between oarfish sightings and major earthquakes in Japan. Scientists believe their surfacing is more likely a result of illness, injury, or strong currents, rather than a prediction of natural phenomena.