Bioluminescence: Small creatures put on a big show in nighttime beach waters

CORPUS CHRISTI, Texas — Have you spotted a ghostly blue glow on the along the waves and waters of local beaches after dark? It might seem supernatural, but this is actually a unique biological phenomenon called “bioluminescence” caused by plankton blooming off the Texas coast.

HRI Coastal Ecosystem Processes Chair Dr. Mike Wetz said the glow is caused locally by two species of dinoflagellates, a type of algae, called Noctiluca and Pyrodinium. Disturbed by activity such as waves or predators, these organisms will release a bright flash caused by an internal chemical reaction. When found in large densities, this can make the ocean water glow, especially along the wave line as their unique natural defense mechanism is triggered by the tumbling waters.

Bioluminescence is thought to be a predator deterrent employed by these organisms, Wetz said, and it may be used to make marine life hoping to prey on these tiny dinoflagellates more visible to even larger predators. This phenomenon is harmless to human and marine life, but puts on a unique show for human viewers. If you want to try to check out some of the bioluminescent waves that have been reported, visit the beaches in Port Aransas and North Padre Island National Seashore after nightfall.