Four New Corals Recorded From Indian Waters

Context:

Scientists have recorded four species of corals for the first time from Indian waters.

Relevance:

GS-III: Conservation, Environmental Pollution and Degradation, Environmental Impact Assessment.

Dimensions in the Article:

• Key Points
• What are Coral Reefs?
• How do they feed themselves?
• Significance of Corals

Key Points:

• New species of Corals were found off Andaman and Nicobar Islands and they all belong to the same family,Flabellidae.

• These new species of azooxanthellate corals. These are group of corals that do not contain zooxanthellae and derive nourishment not from the sun but from capturing different forms of planktons.
• They are deepsea representatives with the majority of species being reported from depths between 200 metres and 1,000 metres.
• They are also reported from shallow waters unlike zooxanthellate corals that are restricted to shallow waters.
• They are a group of hard corals and the four new species recorded are not only solitary but have a highly compressed skeletal structure.
• Significance of the Findings:
• Most studies of hard corals in India have been concentrated on reefbuilding corals while much is not known about nonreefbuilding corals. These new species enhance our knowledge about nonreefbuilding solitary corals.
• The new species not only enhance the national database of biological resources of India but also define the expansion of scope to explore these unexplored and nonreef building corals.

What are Coral Reefs?

• Corals are marine invertebrates or animals not possessing a spine.
• Each coral is called a polyp and thousands of such polyps live together to form a colony, which grows when polyps multiply to make copies of themselves.
• Australia’s Great Barrier Reef is the world’s largest reef system stretching across 2,300 km.
• It hosts 400 different types of coral, gives shelter to 1,500 species of fish and 4,000 types of mollusc.
• Corals are of two types — hard coral and soft coral:
  1. Hard corals, also called hermatypic or ‘reef building’ corals extract calcium carbonate (also found in limestone) from the seawater to build hard, white coral exoskeletons.
  2. Soft coral polyps, however, borrow their appearance from plants, attach themselves to such skeletons and older skeletons built by their ancestors. Soft corals also add their own skeletons to the hard structure over the years and these growing multiplying structures gradually form coral reefs. They are the largest living structures on the planet.

How do they feed themselves?

• Corals share a symbiotic relationship with single-celled algae called zooxanthellae.
• The algae provides the coral with food and nutrients, which they make through photosynthesis, using the sun’s light.
• In turn, the corals give the algae a home and key nutrients.
• The zooxanthellae also give corals their bright colour.

Significance of Corals

• Coral reefs support over 25% of marine biodiversity, including fish, turtles and lobsters; even as they only take up 1% of the seafloor.
• The marine life supported by reefs further fuels global fishing industries. Even giant clams and whales depend on the reefs to live.
• Besides, coral reef systems generate $2.7 trillion in annual economic value through goods and service trade and tourism.
• In Australia, the Barrier Reef, in pre-COVID times, generated $4.6 billion annually through tourism and employed over 60,000 people including divers and guides.
• Aside from adding economic value and being a support system for aquatic life, coral reefs also provide protection from storm waves.
• Dead reefs can revive over time if there are enough fish species that can graze off the weeds that settle on dead corals, but it takes almost a decade for the reef to start setting up again

-Source – The Hindu