11 species of corals identified along Mumbai’s coast

Eleven species of corals have been identified at intertidal zones and rocky shores along the Mumbai coast, mainly along the route where the coastal road has been planned, a study has found.

Corals are marine invertebrates that attach themselves to rocky intertidal regions or the ocean floor. They were identified across eight locations – Haji Ali, Geeta Nagar in Colaba, Marine Drive, Nepean Sea Road, Worli Sea Face, Bandra Bandstand, Carter Road and Juhu – as part of a four-month preliminary study (January to April) by marine biologists from the Mangrove and Marine Biodiversity Conservation Foundation of Maharashtra, an autonomous body that assists the state in coastal marine conservation.

Nine of the 11 species identified were stony or hard corals, which extract calcium from surrounding seawater to create a hardened structure, while two species were soft corals that grow woody cores similar to plants for protection.

Among the hard corals, five species were identified from the Rhizangiidae family, one species each from the Caryophylliidae family and Dendrophylliidae family, and two others identified as reef-building corals from the Siderastreidae family called the False Pillow coral and one species from the Poritidae family, Goniopora. Both the species of soft corals are from the Gorgoniidae family, the study said.

“We found that Haji Ali had the maximum coral distribution of reef-building coral species growing across 25-30 rocks in a tide pool, while the remaining low-tide regions such as Geeta Nagar, Nepean Sea Road and Worli Sea Face had sporadic distribution of corals with smaller colonies. Bandra Bandstand and Juhu had the smallest coral distribution,” said Harshal Karve, marine biologist, Mangrove Foundation.

The 29.2-km coastal road is planned as an eight-lane highway to connect Marine Drive to Kandivli. It will start from Princess Street Flyover to Priyadarshini Circle, connecting a road on reclaimed land till Worli with one end connecting the Bandra-Worli sea link. Work on the 9.98-km first phase of the Brihanmumbai Municipal Corporation (BMC)’s ambitious project is underway with land reclamation at several areas where coral distribution have been identified. However, the study did not give any details on the impact the project could have on coral distribution.

“This is the first detailed study in over two decades,” said Vinay Deshmukh, marine biologist and former scientist, Central Marine Fisheries Research Institute (CMFRI). “As the coastal road construction threatens this habitat, mitigation measures need to be implemented to transplant these corals to a certain distance to ensure they are preserved.”

The state mangrove cell said the study formed the primary database of coral species along Mumbai, but it was part of a yearlong study to document coral distribution across the entire Maharashtra coastline. “Based on rehabilitation of corals in Sindhudurg last year that showed good results, we can carry out coral transplantation and rejuvenation of these species for Mumbai,” said N Vasudevan, additional principal chief conservator of forest, mangrove cell.

Deepak Apte, marine ecologist with research on corals for over 30 years, said, “The coastal road will not have any impact on coral distribution along Mumbai. These are generalist species found across rocky patches along the entire Indian coastline sporadically. As they are fast growing species and not reef building corals, they can recolonise or be restored post construction activity.”

“Numerous representations are being made about marine biodiversity conservation only after the coastal project work started. These species were there post construction of the Bandra Worli Sea Link too, and recolonised post construction. We have appointed the Central Marine Fisheries Research Institute to study the impact on marine life,” said an official from the BMC.