The blue tide spotted at Mumbai beaches


Bioluminescence or light-emitting tide made an appearance on Juhu beach in Mumbai and Devgad, Velas and Murud along thestate's coastline.

  • The phenomenon is called ‘blue tide’, and appears when luminescent marine life make the sea appear a deep shade of blue.
  • The spectacle occurs when phytoplankton (microscopic marine plants), commonly known as dinoflagellates, produce light through chemical reactions in proteins.
  • Waves disturb these unicellular microorganisms and make them release blue light.



  • Bioluminescence is the property of a living organism to produce and emit light.
  • Animals, plants, fungi and bacteria show bioluminescence. A remarkable diversity of marine animals and microbes are able to produce their own light.
  • It is found in many marine organisms such as bacteria, algae, jellyfish, worms, crustaceans, sea stars, fish and sharks.
  • Luminescence is generally higher in deep-living and planktonic organisms than in shallow species.
  • It is an anti-predatory response. Bioluminescence is assumed to startle predators, causing them to hesitate, in a form of predator intimidation.
  • Another explanation is that bioluminescence helps these organisms gather together and make colonies.
  • Bioluminescence has been an annual occurrence along the west coast since 2016 during the months of November and December.
  • While bioluminescence is not common in India, there are several tourist places across the world which are famous for the phenomenon.
  • The Blue Grotto in Malta is one of nine caves near the island of Filfa that produces a phosphorescent glow.
  • The bioluminescence could have been caused by heavy rain, fertilizers run off, discharge of sewage into the ocean.
Print Friendly and PDF
blog comments powered by Disqus