Glow-in-the-Dark Critters: Exploring Bioluminescence

Anglesey, UK - Photo Credit: Kristofer Williams

Anglesey, UK – Photo Credit: Kristofer Williams

Have you ever seen photos of a glowing, other-worldly body of water? As the waves crash, the surface seems to ignite with a glow-in-the-dark hue. While it certainly looks like something out of a science-fiction movie, that glow – bioluminescence – is very real and very alive. If you have ever had the opportunity to see it in person, you know it is unmistakably beautiful as well.

Bioluminescence occurs when living creatures with special light-emitting cells start a chemical reaction in their bodies. There is a special substance these creatures carry (luciferin) that glows when it is oxidized. This glow is more than just a party trick – ocean creatures use their glow to attract prey, protect themselves from predators or attract mates. Blue is the most common light emitted, but there is a variety of colours and purposes for bioluminescence depending on the species.

Bioluminescence JellyfishThe anglerfish uses a bioluminescent dangling appendage to lure prey within its grasp. Lanternfish use their bioluminescent bellies to break up the silhouette of their bodies from below, making it more difficult for predators to see them. And ostracods, which are small shrimp-like crustaceans, use their light to signal to mates when they are in close range. Many species of squid and jellyfish also have bioluminescent abilities, too.

However, even the tiniest creatures can make quite the impression. Some of the most breath-taking views occur when microorganisms get caught up in a tide and all light up together and the algae bloom known as red tide lights up when it is disturbed.

Even non-divers enjoying a casual walk along the beach can enjoy front seat tickets to the ocean’s show – check out these 5 bays which offer some incredible bioluminescent sights:

Red Tide, San Diego - Photo Credit: 'slworking2'

Red Tide, San Diego – Photo Credit: ‘slworking2′

  • Mosquito Bay, Puerto Rico
  • Gippsland Lakes of Victoria, Australia
  • Ton Sai in Krabi, Thailand
  • Anglesey, UK
  • Reethi Beach, Maldives

Many bioluminescent creatures live in shallow areas, and once you learn the basics of night diving you will know exactly where to look. Just remember to turn your dive light off while looking for the glow to get the best view.

Contact your local PADI Dive Shop to learn more about the PADI Night Diver specialty course. In no time at all, you will be ready to explore the glowing mystery of the sea at night.