5 Deep Sea Creatures That Glow In the Dark

Sea Creatures That Glow In the Dark

The deep sea is full of remarkable creatures that seem to be straight out of a science fiction movie. But we’re only scratching the surface (pun intended) of the vast biodiversity of our planet’s oceans, so who knows what could be waiting as we explore further and deeper.

Because the deepest parts of the ocean get so little light to penetrate through thousands of feet of salt water, many organisms have adopted methods of functioning in the dark depths, one of which is bioluminescence, which is exhibited in roughly three quarters of deep sea creatures. If you want a deep dive into the subject (again, pun intended), you can check out this scholarly report on deep sea creatures that glow, but if you just want a handful to check out, keep reading here.

1. Kitefin Shark

The Kitefin Shark, or Seal Shark, are bioluminescent deep sea creatures that can be found in tropical and semi-tropical waters almost all the way around the globe and is the largest shark known to exhibit bioluminescent traits. But it’s not that big, because one of the uses of the Kitefin Shark’s glowing underbelly is likely to blend in with its surroundings, a tactic known as counter-illumination. This protects the Kitefin from larger predators. By the way, we offer the Voyage Bracelet, which enables you to track a shark that is tied to your individual bracelet.

2. Alarm Jellyfish

And speaking of predators, the Alarm Jellyfish has an ingenious method of protecting itself from them by using its glowing properties. How can you get one scary deep sea creature off your back? Call in a bigger one! Whenever it is being attacked, the Alarm Jellyfish emits flashes of blue light that attracts other predators to prey on the one that’s threatening the jellyfish.

3. Barbeled Dragonfish

This scary deep sea creature uses a glowing barbel under its jaw like a fishing rod to attract prey.

4. Giant Glowing Squid

The largest bioluminescent deep sea creature in the world – that we know of – is the Giant Glowing Squid, which reaches over seven feet long and 130 pounds. The creature emits short flashes of light either to blind its prey or measure the distance to its next victim. 

5. Glowing Coral

Okay, so how about a deep sea creature that glows for a reason other than fending off predators or attracting prey? While coral in shallow parts of the ocean get their energy from the light of the sun, in deep water the little bit of sunlight that reaches the ocean floor isn’t ideal for the coral’s needs. To survive, many types of coral transform the blue light from the sun into red light using a fluorescent protein in order to enable a symbiotic algae known as zooxanthellae to photosynthesize and create food. It’s a little circle of life.

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