The invasive Kappaphycus alvarezii seaweed, which smothers and kills coral reefs, has spread its wings
to coral reef areas in Valai island in the Gulf of Mannar (GoM) and set to invade new coral colonies in the marine national
park. Macrofaunal
and fish density decreased when
Kappaphycus cover increased.
After invading Shingle, Kurusadai and Mulli
islands in Mandapam cluster of the GoM, the red algae invaded Valai
island along Kilakarai coast
following its cultivation in south Palk Bay.
Findings:
In the report submitted to the Ministry of Environment, Forest and
Climate Change (MoEFC) by
the Reef
Research Team (RRT) of Suganthi Devadason Marine Research Institute (SDMRI), Thoothukudi, said that the destructive algae had
invaded the reef areas of Valai Island, Palk Bay Gulf of Munnar. The research
team counted 32
coral colonies of Acropora nobilis affected by Kappaphycus algae. The team said that the
algae was firmly attached to the coral colonies and started forming a mat over
them. It would eventually smother and kill corals.
Steps taken:
A 2005 Government Order had restricted
cultivation of the exotic seaweed only to the seawaters north of the Palk Bay and South of
Thoothukudi coast.
The Forest department is to take up the issue
with agencies, which promoted the cultivation of the seaweed. The department
had been carrying out manual removal of the seaweed every year since 2014 to protect coral reefs.
