Abyss Scuba Diving

What Is Bioluminescence?



Have you ever seen the ocean at night and been mesmerized by the flashes of light? This is called bioluminescence, and it's a really cool phenomenon! In this blog post, we will discuss what bioluminescence is, how it works, and some of the animals that use it. Stay tuned for some amazing photos and videos of bioluminescent creatures!

So, what is bioluminescence?  Bioluminescence is the name for the light produced by some animals. This light is the result of a chemical reaction, and some animals make the necessary chemicals themselves, while others absorb them from their food. There are also some animals that allow bioluminescent organisms to live inside them, forming a symbiotic relationship. Most bioluminescent animals live in the ocean, but there are also some that live on land.

Diver exiting from a night dive in Bioluminescent water


How does bioluminescence work?

Light is produced when a chemical called luciferin reacts with oxygen. Luciferin is oxidized and then emits light. This process is called chemiluminescence. Some animals have special organs that contain luciferin and oxygen, and these organs are called photophores.

 There are many different ways that animals use bioluminescence. For example, some use it to attract mates, while others use it to lure prey. Some animals also use it as a defence mechanism to startle predators or to confuse them.


Now that we know what bioluminescence is and how it works let's take a look at some of the animals that use it!

One of the most well-known bioluminescent animals is the firefly. Fireflies produce light in their abdomens, and they use this light to attract mates. When two fireflies of the same species meet, they flash their lights in a special pattern. If the patterns match, then they know that they are suitable mates.

Another well-known bioluminescent animal is the glow worm. Glow worms are actually not worms at all but the larvae of a type of fly. These larvae produce light in order to attract prey. When an insect flies into the light, the glow worm grabs it with its mouthparts and eats it.

Bioluminescence and night diving magic

Night diving and bioluminescence often go hand in hand. When you switch your dive torch off at night, tiny plankton specs light up in the darkness, giving the underwater an ethereal look. This is due to bioluminescent algae, which are single-celled marine organisms that produce a bluish-green light. The most common type of bioluminescent organisms are dinoflagellates, of which Noctiluca scintillans (otherwise known as sea sparkle) is one. So next time you're night diving, don't forget to look out for these amazing creatures!

Ship Rock on a full moon is one of the best night diving locations to see bioluminescence in action. The sea pens here respond to being touched by glowing blue light in the dark through a process called bioluminescence. This occurs when a chemical reaction takes place within the sea pen, and energy is released in the form of light emitted. These showy displays resemble the lights on a movie marquee as the flashes circulate up and down the rod-like stem of the sea pen and are used to startle potential predators.

Sea Pen at Ship Rock

Pineapple fish, also found at Ship Rock, are also known as the "port-and-starboard" light fish, as they have a pair of bioluminescent organs that are reminiscent of navigation lights on ship. These organs are actually light-producing bacteria that live symbiotically inside the fish. When the fish opens its mouth, the light from the bacteria is emitted, providing camouflage from predators and attracting prey.

Pineapple fish

One example of marine animals that produce light is the anglerfish. The anglerfish has a long filament that protrudes from its head, and at the end of this filament is a light-producing organ. The anglerfish uses light to attract prey, and when an unsuspecting victim comes close, the anglerfish quickly grabs it with its mouth.

Another ocean creature that uses bioluminescence is the squid. Deep sea squids use light for many different purposes, such as attracting mates, luring prey, and startling predators. They can also change the colour of their light to communicate with other squids.

There are many other animals that use bioluminescence, and we have only just scratched the surface! We hope you found this blog post interesting, and be sure to check out our website for more information about all sorts of fascinating animals.

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