BILLIONS of jellyfish-like creatures have washed up on numerous beaches on the West Coast, baffling scientists and locals alike.

Beaches all the way from San Diego to British Columbia are now covered in a mysterious species of fish known as “by the wind sailors,” or their scientific name, velella velella.

Not much is known about these four-inch fish distinguished by a gas-filled fin, which tells us that wherever they travel is entirely dependent on the wind and currents, Daily Mail reports.

They are very similar to jellyfish, both in looks and the way they sting their prey, though their stingers are too weak to penetrate human skin.

Their diet consists of only plankton and they regularly travel by the million.

Velella velella sightings have become more and more regular since they were seen on a Humboldt beach a little over a month ago.

And now over a thousand per meter have been counted along the California shores.

They live thousands of feet below the surface so, like many other sea creatures, their influx is believed to be caused by rising water temperatures.

This article was written by Sean Levinson from Elite Daily and was legally licensed through the NewsCred publisher network.