We all once in our lifetime have dreamt of kayaking in the shimmering ocean. Have you ever wondered what makes the ocean shimmer? Moonlight triggers the emergence of world’s strange creatures from the depths, painting the waves blue in the dark. Such a magical phenomenon can be witnessed after sunset.
So, what exactly makes the ocean glow? Dinoflagellate or moonlight?
Bioluminescence makes the ocean glow. Although bioluminescence is triggered by planktonic organisms known as dinoflagellates, it is a pretty mind-blowing phenomenon. When disturbed, these dinoflagellates emit blue light. Therefore, making them visibly sparkle on the bay, over a wave crest, or when a paddle or hand runs through them.
The much-hyped shimmering bays in Jamaica and Puerto Rico are one of the best places to witness the bioluminescence. Nevertheless, such marvels can be seen where there are a dense gathering of dinoflagellates.
Red tides are also spotted during daytime if the population of dinoflagellates increases triggering rapid red-brown blooms which are less attractive. However, not all but some red tides can be poisonous.
- Glow-in-the-dark animals
Bioluminescence i.e. the emission of visible light by an organism is the result of a natural chemical reaction. These reactions are common in marine life such as squids, mollusks, and fishes. Most of the species in the deep sea are bioluminescent, whereas, in the shallow waters, these bioluminescent organisms display their lights during night time.
Dr. Matt Davis adds that some fishes like flashlight fishes have specific pouches under their eyes. They can rotate these pouches to expose the light emitted from the bacteria, and thus use this glow-in-the-dark light to communicate and to hunt for food.
Predation, camouflage, and defense are some of the reasons behind the emission of these lights.
- Planet’s biggest orgy triggered by moonlight
If you are a coral on the Great Barrier Reef of Australia, then nothing can compare a romantic moonlit coral night. The world’s biggest orgy is caused by this moonlit night every spring, once a year.
In the window of barely 30 to 60 minutes, over 130 coral species release their sperm and eggs in the water. The magnitude of this mass hatching sets this event as the most amazing in-sync behavior in the monde naturel.
Moonlight sparks the incident by acting as an alarm or synchronizer perhaps with the other ecological signals such as water temperature, tides to prompt the release time of the gametes and sunset timings. Corals also seem to have photoreceptors that can detect the phases of the moon, further fine-tuning the process of gamete release.
- Celestial light for sharks and seals
Celestial nights for some seals spell danger. Around 60,000 cape fur seals run the gauntlet of being killed by great white sharks, during winter on Sea Island in False Bay, South Africa. These sharks patrol the sea and pick these seals when they enter and exit the water. The silhouette of the seals against the surface makes them an easy target for the predators waiting below.
Although, the majority of the shark attacks on the seals happens at dawn. But, on the day of full moon, the attacks after sunrise reduced.
For their safe navigation, seals can rely on a different celestial feature- the stars.
- The emergence of strange creatures to the surface every night.
Rarely seen creatures often migrate to the ocean’s surface under the cover of the darkness to feed themselves.
One of them is the Humboldt squid, aka the jumbo squid. It is one of the most stunning aquatic creatures you can spot lurking in shallow waters. During day-time, the squid waits in the deep Eastern Pacific Ocean alongside the American west coast and during night-time, they migrate towards the shallow waters in search of dinner. This event is known as diel or vertical migration which is extremely common in the marine animals.