As night falls on certain beaches around
the world, the waves glow with an eerie blue light: tiny, neon dots that make
it look as though stars are washing up on shore.
The surreal scene arises not from magic,
but from plankton that have evolved to glow in order to startle or distract fish
and other potential predators. Some scientists call it the “burglar alarm effect”:
by lighting up, the plankton draw even larger predators that, in turn, eat the
animal threatening them. The phosphorescence only occurs when the microorganisms,
which exist worldwide, are agitated – such as when the water crashes onto the shore,
someone steps on the wet sand or a paddle hits the waves.
The phenomenon’s effects can vary depending
on time of year and weather, so sightings cannot always be predicted. Even so,
here are three spots where you’re most likely to see the sea shine with its own
to the Indian Ocean archipelago say they have had the most luck seeing the
blue glow from about July to February, especially during a new moon since the
darkness of the sky helps intensify the light. The bioluminescence can occur
throughout the country’s 26 atolls, but some of the most spectacular
photographs have been captured on the grouping’s eastern islands, including Mudhdhoo,
Mosquito Bay on the island of Vieques has
the nickname of Bioluminescent Bay (often called Bio Bay) for the bright
plankton that illuminates the water.
bay went dark in January 2014. Some scientists theorise that a wind shift
pushed many of the microorganisms out of the bay, but the various factors that
contribute to the bioluminescence make it difficult to say for sure.
Thankfully, the bay brightened again in
June, although at a lower intensity. Though no one knows if the bay will return
to full strength, tour operators are still running kayak tours Fridays through
Sundays, as scientists work to study the bay the rest of the week in hopes of
preserving the magical glow.
There is bizarre bioluminescence in this
Southern Californian city, too, caused when millions of phytoplankton form a
group of algae so big they discolour the nearby water. Surfers see a “red tide”
every few years, when these algal blooms give the sea a reddish tint by day and
a bright blue phosphorescent glow by night. When the right combination of water
temperature, wind, darkness of the sky and other factors come together, surfers
and swimmers can glide through the water with a glow illuminating
their way. Though some algal bloom can be harmful, the species common to San Diego, Lingulodinium
polyedrum, is not considered to be toxic.