Mother Nature puts on some incredible shows. Lightning, fireflies, the aurora borealis, and even sunrises and sunsets bring a sense of awe – even to the most tech-savvy, world-weary viewer. There’s one natural light show you’ll only experience in water: Marine bioluminescence.
Nature’s Magic
If you’ve ever seen a firefly, you’ve seen the natural magic that is bioluminescence. If you’ve ever been on a boat at dusk, dawn, or during nighttime hours, and seen the wake or prop wash glowing, you’ve seen bioluminescent plankton. While there are many forms of natural luminescence, there are only a few land creatures that have the ability to glow in the dark. Luckily for us divers, there are many others dwelling in the water. And, while bioluminescent land animals are only encountered in a few places on earth, almost all ocean environments contain life that glows when the light of the sun goes away. Even more incredible, scientists estimate that about ninety percent of deep sea creatures have some form of bioluminescence, and this makes sense, as the sun’s light does not penetrate into the deepest parts of the oceans.
There are many ways you can experience the beauty of marine bioluminescence. On night dives, you might stumble upon algae that puts on a show as you and your dive buddies make your way through the water. It’s fun to see the outline of your buddy, illuminated by millions of tiny creatures. Hold still and wave your hands in front of you, and you can create your own light show, with swirls, bursts, and streams of green or blue color. On nights when the algae are present, you can also walk on the beach, sticking to the area where the water is washing up onto shore. You may see the waves glowing, and if you look behind you, you might see your footprints shining in the darkness.
Another common way to experience bioluminescence while diving is to choose dive sites where comb jellyfish are present. These little jellies are translucent, with a body shape reminiscent of a football. They possess eight streamlined rows of cilia. They are commonly found in bays and salt lagoons, and as they move through the water, they leave tiny trails of bluish-green color in their wake.
There are many fish and corals that exhibit bioluminescence, too. The deep sea anglerfish is one example of an animal that uses its bioluminescence to attract prey. Though you’re not likely to encounter these fish while diving, if you take a submarine trip into water too deep for recreational diving, you might encounter these fish and other weird deep sea life forms.
A bioluminescent fish you might encounter in huge numbers is the flashlight fish. One of the best places to see these fish is at the wreck of the SS President Coolidge in Vanuatu. While it’s great fun to dive this ocean liner wreck during the day, you’ve got to dive it at night to see the flashlight fish. They school in the cargo hold at a depth of about 30 meters. You do need to be wreck certified to get the most from this dive, since mild penetration is involved.
No matter what type of show nature puts on, take a minute to pause and appreciate it. You don’t have to spend a long time looking, but the beauty of all types of phenomenon can help you breathe deep, relax, and gain a new appreciation for life on earth – bioluminescent or not.