Last night we were treated to a beautiful bioluminescent show off the stern of the ship. Standing on the fantail, we watched glowing blobs emerge from beneath the ship as we sailed over the water. This light show was likely the result of sailing through a dinoflagellate algal bloom. Under certain conditions, dinoflagellates bloom in dense layers at the ocean surface. The ocean looks reddish-brown in daylight and has a sparkly sheen at night as the algae move in the waves. The shoreline picture below shows what we saw in the wake of the ship. Since we were out in the deep ocean, the only light we saw was from the bioluminescent organisms and the stars. Wow! It was pretty!
Bioluminescent organisms live everywhere in the ocean – from surface to seafloor and coast to open ocean. They are very common in the deep ocean where sunlight only penetrates the top of the water. Since the ocean covers more than 70% of Earth and can be miles deep in some places, I’d say that bioluminescence is the most common form of communication on the planet!
Bacteria, algae, jellyfish, worms, crustaceans, sea stars, fish, sharks, squid, and many other types of organisms use chemical reactions to produce light energy within their bodies. The critical molecule is luciferin and it reacts with oxygen to produce light. Creatures control when they light up through their body chemistry and nervous system. Calcium ions in the body usually start the reaction when there is a physical disturbance (response to attack) or when the animal is trying to attract a mate or a meal.
I have bioluminescence too! and I mostly use mine for hunting. I have red patches below my eyes that produce a red light to let me see short distances around me. Red is invisible to most creatures down here because red wavelengths don’t travel far in water. I can see red – I’m special that way – and I use my red light to scope out tasty organisms to snack on. I also have green patches on my cheeks. I produce green light with them to trick fish into coming close thinking they’ll get a snack. Mwahaha! When they get close, I snap them up in my huge jaws and swallow them whole! Heehee, I like that part! I know it’s tricky and might sound downright mean, but it’s how I make a living.
Glowing in the dark,