Stories From the Coral Triangle

When jellyfish glow in the dark

When a satellite passes over the Coral Triangle at night, darkness blankets the region save for the bright lights of cities that never sleep such as Singapore, Manila, Jakarta, and other metropolises. But if the satellite could train its electronic eye to the depths of oceans, it would pick up something even more beautiful and strange: pulsating or flickering lights powered by a completely natural process - bioluminescence.

Chemical beauty

Bioluminescence allows fireflies to shine, makes waves glow at night, and powers deep-sea anglerfishs’ lure. The way this works is that chemicals activate electrons in the animal’s body, the result of complex (and not always well understood) pathways involving stimuli, enzymes, and energy shifts. This amazing faculty manifests itself in thousands of species, including jellyfish.

Scientists estimate that about 1 in 2 of jellyfish are bioluminescent, including siphonophores (related to the dangerous Portuguese man-o-war), medusae, sea pens and other soft corals, and ctenophores (also known comb jellies).

Deep down, a tactical display of light

To see the largest diversity of bioluminescent jellyfish, one must head down to the deep sea. Here we meet atolla, a jellyfish known for its “burglar alarm.” When this species is attacked, it sets off a bright display of lights that can be seen for 300 feet (about 100 metres). According to scientists, this phenomenon is intended to attract an even larger and fiercer predator. If the new predator picks on the jellyfish’s attacker, then it might survive.

Good reasons to shine

Indeed, most jellyfish use their “lights” as a defense against predators. Comb jellies produce bright flashes to startle their attacker, while others such as siphonophores can either display a chain of light or release thousands of glowing particles into the water in order to confuse the predator. A more fickle tactic involves producing a glowing slime that sticks to predators, making them visible and hence vulnerable to their predators.

In the cutthroat world of the deep Coral Triangle, the ability to display the right lights at the right time is a question of life and death. For us, it is another example of the region’s marine wonders.

Next Stories
The Coral Triangle’s Ecotourism Destinations
From popular tourism hotspots such as Bali and El Nido to far-flung outposts, the Coral Triangle offers a bewildering array of environment-friendly resorts. Here are three such places.

Back to Story Listing
View Recent Purchases
Share: Share on Facebook Share on Twitter Share on Google+ |