Blue Tides

Why in news?

• Blue Tide has been Spotted Along Juhu, Ratnagiri Beaches.

About Blue Tides:

• The phenomenon called 'blue tide' happens when luminescent marine life makes 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 makes them release blue light.
• Although beautiful the tides may also be a signal of danger as many of the species in this group are toxic.
• If dinoflagellates reproduce rapidly, they may cause so-called ‘red tides’ which are associated with wildlife mortalities and harmful human exposure.
• The production of natural toxins such as brevetoxins and ichthyotoxins are harmful to marine life.
• The primary cause of these blooms is eutrophication which ocean makes overly enriched with minerals and nutrients which induce excessive growth of algae.

What is Bioluminescence?

• Bioluminescence is the property of a living organism to produce and emit light.
• Animals, plants, fungi, bacteria and a remarkable diversity of marine animals and microbes show bioluminescence. 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.

PRELIMS QUESTION

Consider the following statements:
1.Oligotrophic lakes host a larger number of organisms when compared to eutrophic lakes.
2.Mesotrophic lakes are lakes with an intermediate level of productivity.
Which among the above statements is/are correct?
(a)1 only 
(b)2 only 
(c)Both 1 and 2
(d)Neither 1 nor 2

Answer to prelims question