Are beached oarfish a warning of impending earthquake?

The beached yesterday. Picture courtesy of the St Bernard tourism office
Two fish associated with impending earthquakes washed ashore in Southern yesterday (Wednesday, August 9).

Two oarfish — which are known in Japan as ‘The Messenger from the Sea God’s Palace’ — were found in a protected reserve in Saint Bernard.

One measured 3.7 metres, with a weight of 20kg, while the other was 4.4 metres and weighed 50kg.

In recent history, about 20 of the deep-ocean fish were found washed ashore in the days leading up to the 2011 Tohoku earthquake and tsunami that devastated Japan.

While there is no direct scientific evidence to support the idea these fish are sensitive to seismic activity, it should be remembered that science itself has no way to predict earthquakes.

However, their deep sea habitat, living in close proximity to undersea fault lines does suggest a rational basis for the ancient Japanese myth.

Rachel Grant, a lecturer in animal biology at Anglia Ruskin University in Cambridge, England, has begun a study to test the idea.

“It’s theoretically possible because when an earthquake occurs there can be a build-up of pressure in the rocks which can lead to electrostatic charges that cause electrically-charged ions to be released into the water,” she said.

“This can lead to the formation of hydrogen peroxide, which is a toxic compound. The charged ions can also oxidise organic matter which could either kill the fish or force them to leave the deep ocean and rise to the surface.”

Another possibility, she added, was that prior to a quake there is a release of large quantities of carbon monoxide gas, which could also affect oarfish.

“The geophysical processes behind these kinds of sighting can happen before an earthquake,” she said.

Dr Grant said that she has built up a database of several hundred sightings over the past two-and-a-half years and will now see if there are links between the sightings and any earthquakes reported by the US Geological Survey within a 500 mile radius.

“We do know that there’s not an earthquake after every sighting, but we are going to see if there is an increased probability of oarfish being seen prior to an earthquake.

“It may be due to seismic activity or it may be due to other factors unconnected with earthquakes, such as infrasound caused by underwater activities, such as military submarines, or pollution,” she said.

Oarfish are usually found at depths of 1,000 metres and very rarely above 200 metres from the surface. Long and slender with a dorsal fin the length of its body, the resembles a snake.

It is believed that its rare appearances on the surface of the sea gave rise to legends about sea serpents.