Context

• The government plans to set up a seaweed park in Tamil Nadu, ignoring the threat that Kappaphycus, a widely grown invasive seaweed, poses to corals in the Gulf of Mannar Marine National Park

Kappaphycus alvarezii

• Kappaphycus alvarezii, the elkhorn sea moss, is a species of red algae.
• It is an IUCN red-listed species.
• This invasive seaweed smothers and kills coral reefs.
• It is being intentionally introduced in marine waters worldwide for the production of kappa carrageenan
• Kappa-carrageenan, a polysaccharide extracted from the alga that finds use in industrial gums and as a smoothening agent in ice cream, toothpaste, jellies, medicines, and paint 

Invasive Alien species

• Any non-native species that significantly modifies or disrupts the ecosystems it colonizes is referred to as invasive in nature.
• Common characteristics include 
  • Rapid reproduction and growth
  • High dispersal ability, 
  • Phenotypic plasticity (ability to adapt physiologically to new conditions), and 
  • Ability to survive in a wide range of environmental conditions.

Global Scenario

• Kappaphycus is a native species of Philippines.
• Commercial production of Kappaphycus began in the 1960s.
• It has since been introduced in over 20 nations. 
• The invasive species has also caused considerable damage to Coconut Island in Hawaii, Cubagua Island in Venezuela, Zanzibar in Tanzania, etc

Indian Context

• The rich coral reefs of the Gulf of Mannar Marine National Park have been facing an increasing threat from Kappaphycus.
• It is said that ocean currents have been transporting fragments of the alga into the Gulf of Mannar islands 
• Further, the coral reefs of Valai Island were dying due to stress from Kappaphycus invasion

Findings

• According to ICAR, In 2021, India cultivated around 34,000 tonnes of seaweed
• Between 2001 and 2013, the production of dry Kappaphycus jumped from 21 tonnes to 1,490 tonnes.

Threats posed by Kappaphycus alvarezii on Corals

• Macro-algae such as seaweed compete with coral for space on the reef.
• Unlike native seaweeds, which typically grow on dead corals, kappaphycus seeks live corals to thrive on.
• It forms a thick gelatinous mat over corals, eventually smothering and killing them.
• Once Kappaphycus establishes itself firmly, it is impossible to separate it without damaging the coral colony. 

Major Concerns

• Kappaphycus causes damage to corals and their services, potentially robbing the fishing communities of fish catch, their main source of income.
• Further, the commercial cultivation of Kappaphycus in Palk Bay may affect the efforts to conserve the dugong population.
• Seagrass beds, which are Dugong’s prime foraging grounds are likely to be impacted.
• Also with increased Kappaphycus cover, the macrofaunal and fish density can decrease.

Conclusion

• Invasive species can alter natural habitats posing a great threat to flora and fauna.
• It is necessary to undertake an Environmental Impact Assessment(EIA) before the introduction of alien species into native habitats.