You may have thought that amazing scenes in films like Ang Lee’s Life of Pi or James Cameron’s Avatar where the waterscape lights up as the protagonist moves through the scene is only science fiction and special effects, but in many waters around the world it is a real phenomenon called Bio-luminescence.
Bio-luminescence is a form of visual inter / intraspecie communication between marine organisms and is very common in open water species. Light is usually produced at night when you disturb a certain type of microscopic plankton called Dinoflagellates which can be very fun when waving your arms around to make underwater angels. It can light up beaches as the motion of the waves crashing disturbs the plankton or simply swimming through a dense patch of them can light up each movement. The light comes from a chemical reaction similar to a glow-stick but inside the organism that produces light as a bi-product. The reaction involves a molecule called luciferin, an enzyme luciferase, oxygen and the energy transporting chemical ATP. The light produced is usually in the blue-green light spectrum as these wavelengths travel further through the water and are a more effective means of communication. The light produced is known as “cold light” which means that from all of the energy produced from the reaction, less than 20% is lost as heat.
The light production is a defence mechanism that is supposed to startle and distract potential predators or attract competing predators. Because the intensity of the light is proportional to the amount of disturbance, moving boats have the best light show. Often occurring best with algae blooms, the light shows only occur at night and tend to be more intense with moonless nights as the Dinoflangellates are photosensitive and illuminate best at night.
Certain places around the world are known for their high concentration of Dinoflangellates and other Bio-luminescent organisms, Puerto Rico especially has many areas known as Bio-Bays with amazing light shows. These night-time light-shows can be found from places like Australia and the Maldives to Belgium and even Norfolk. At certain times of the year algae blooms in Cairns, Australia, bringing with it a high concentration of Dinoflangellates that light up the waters. Areas around the southern United States such as San Diego and Cortez, FL have seen these blooms that travel down to the Caribbean. Countries like the Maldives, Vietnam, Thailand and Indonesia can also have high concentrations of Dinoflangellates but they can still be found in areas like the Red Sea, some in-land lakes around the world.
Where have you seen any Bio-luminescence? Do any of you have any amazing stories of Bio-luminescence around the world or even at home in the UK? Post a comment below.