Here’s my story seeing a fireclam while scuba diving in a cave in Vanuatu.

Diving in the dark depths of a cave is an unparalleled experience, especially when you have the chance to witness the majesty of Mother Nature. I had the opportunity to scuba dive in an underwater cave off the coast of Vanuatu.

The fireclam is a species of bivalve mollusk that inhabits the depths of coral reefs and sandy ocean floors. It’s an impressive creature, standing out among its neighbors thanks to its vibrant colors.

Thinking I was witnessing bioluminescence, I made some extra research. I found out that the apparent flashing-light display of this clam is not a bioluminescence phenomenon, but is instead coming from reflection of the ambient light (sun or diving light). The clams have a highly reflective tissue on the very outer edge of their mantle that is exposed and then hidden very quickly, so the change back and forth from the white reflective tissue to the red tissue creates the appearance of flashing.

The fireclam was a dazzling sight to behold, and I’ll always remember this magical experience. It was my first time ever seeing one in the wild, and it certainly made for an exciting dive. I’m sure that when many divers come across these creatures, they are just as awed by them as I am!