Flashlight Fish

These intriguing fish can be found living in caves and dark crevices from the west of the Indo-Pacific ocean to the south of Japan, and also in the Great Barrier Reef in Australia. However, as a predominantly nocturnal fish they are very rarely seen by divers. They will actively avoid lights and swim away to shelter so even a late night diver may struggle to see them as their flashlight will scare them off.

Their bodies are dark with a line that runs all the way along, but what makes them really stand out is the bright bean shaped organs that sit below their eyes. This light is created by millions of bioluminescent bacteria that produce the bright-green light. This light can be turned on and off by rotating the bacteria inward and outward. It is a very useful skill that they use to communicate and as a hunting method. They will blink the light to draw the attention of their prey and as they move in they will turn it off so their prey is left in darkness.

Although the bioluminescent organ is prominent in deep sea fish, Flashlight fish are one of the very few who have this ability who make their way to the surface in winter months as they prefer warmer water. The light they produce can be seen from upwards of 30 metres away and depending on the size of the group can be incredibly vibrant. They have a very fast blinking ability with the ability to blink their lights from around 50 -75 times a minute.