Bioluminescence: The Ocean’s Night Lights

As the sun sets and the deep darkness of nighttime in the middle of the ocean surrounds us, we don’t know which way to look. From above, we get an impressive view of the milky way, but below, we see some stars of a very different kind…. bioluminescent plankton!

Bioluminescence occurs when certain marine organisms, such as plankton, jellyfish, and squid, produce light through a chemical reaction. This process relies on a molecule called luciferin and an enzyme called luciferase. When oxygen is present, luciferase triggers a reaction with luciferin, resulting in the emission of light.

Why do they do this you may ask? Self-defence. When tiny plankton like dinoflagellates are disturbed or scared – like when a 2000 tonne research vessel hurtles towards them – they emit the light as a warning in attempt to scare off potential prey. Fascinating!

Shiny and bright phytoplankton!