Mysterious Velella Washing Up on California Coast
Creatures like these have been washing up along the California coast.
Nearly 180 species of fish that glow have been identified in a new study led by scientists from theAmerican Museum of Natural History
. The study, published in Thursday'sPLOS ONE
, shows how the fish absorb light and eject it as a different color for varied reasons including communicating and mating. Above, a biofluorescent surgeonfish (
©AMNH/J. Sparks, D. Gruber, and V. Pieribone
A green biofluorescent chain catshark (
A red fluorescing scorpionfish (
) perched on red fluorescing algae at night in the Solomon Islands.
©AMNH/J. Sparks and D. Gruber
A triplefin blennie (
.) under white light (above) and blue light (below).
It's not just hordes of anchovies attacking the California coastline this summer, as a small, jellyfish-like creature with a cool blue hue has been washing up by the millions along shores up and down the state's coast since the middle of July.
The beach-crashing creature's full name is Velella velella (not a typo; it's the only species in its genus), sometimes referred to as "by-the-wind sailors," because they live on the surface of the water and are at the mercy of the winds for all of their travel plans.
As befits their nickname, velella have a kind of sail affixed to their tops, which is what allows them their out-of-control seafaring. They have few predators, although some sea slugs and water-bound snails will eat them.
It's not unprecedented for the creatures -- just a couple of inches long -- to be swept ashore in mass die-offs, but it's a bit late in the summer season for the mass strandings to occur. The reason for the tardy appearance remains a mystery.
The vellella isn't specific to California coastal waters but is happy in the warmer parts of oceans the world over. Despite this ubiquity, scientists still don't know a whole lot about their lives.
We do know, however, that they're carnivores and will dine chiefly on plankton fetched by thin tentacles that dangle beneath the water's surface and grab whatever good eats come along.
Velella can't live out of water for terribly long, though, and those creatures that aren't lucky enough to be pulled quickly back out by the tide will die by dry-out within a couple of hours.