NOPR Collection:

Emergence of coral rubble islet near Manoli Island, Gulf of Mannar, India

Fri, 01 Nov 2024 00:00:00 GMT

Title: Emergence of coral rubble islet near Manoli Island, Gulf of Mannar, India Authors: H Ramesh, C; Shunmugaraj, T; Mani Murali, R; Koushik, S; V R Murthy, M Abstract: Coral reefs of the Gulf of Mannar region, India, are damaged severely by bleaching events, anthropogenic stressors, coral diseases, and invasive species. The fate of dead corals has not been investigated in this region. In this study, dead corals forming a coral rubble islet was identified about 800 m away from the southeast of Manoliputti Island, Gulf of Mannar. The 50 m-long rubble islet consisted mainly of dead Acroporidae and Faviidae corals. Field observations indicate that the convergence of waves from various directions around the coral rubble islet may be a primary factor in its formation. Current velocity and wind patterns data from satellite support that the collision between wind and current would facilitate the formation of a coral rubble islet. Further studies are required to understand the long-term influence of extreme waves, currents, and longshore drifts on this coral rubble islet's accretion, shape, and shift. The study infers that the instability of the seafloor topography, combined with the vulnerability of Acroporidae and Faviidae corals to hydrodynamic forces, may have led to the substantial generation and accumulation of coral fragments over the past two decades. Thus, further studies on the sediment texture of reef flats and conservation and restoration of these corals are needed urgently to protect coral reefs in the Gulf of Mannar Page(s): 699-708

Assessing the invasion and impact of coral-killing sponge Terpios hoshinota on coral reefs in the Gulf of Mannar marine biosphere reserve: A case study and review

Fri, 01 Nov 2024 00:00:00 GMT

Title: Assessing the invasion and impact of coral-killing sponge Terpios hoshinota on coral reefs in the Gulf of Mannar marine biosphere reserve: A case study and review Authors: H Ramesh, C; Shunmugaraj, T; Koushik, S; V R Murthy, M Abstract: The encrusting cyanobacteriosponge Terpios hoshinota Rützler & Muzik, 1993 has caused severe and often irreversible damage to coral reefs and associated benthic communities in the Indo-Pacific region. Despite its ecological significance, the distribution patterns of T. hoshinota in Indian reefs is poorly understood except for limited reports. Hence, a comprehensive investigation was conducted between September 2018 and August 2019 to assess the range extent of T. hoshinota across 21 islands within the Gulf of Mannar Marine Biosphere Reserve (GoMMBR), located along the southeast coast of Tamil Nadu, India. Utilising coral video transect methodology, a notable outbreak of T. hoshinota primarily on Montipora digitata reefs in Thalaiyari and Valai Islands was documented, where approximately 42.8 % and 45 % of M. digitata coral cover were killed. Furthermore, mild to moderate infestations of T. hoshinota were observed on Porites corals in seven additional islands within the GoMMBR. There were no other factors except T. hoshinota that caused the corals to die (no polyps on the corals). The rapid spread of T. hoshinota from infested corals to other healthy corals was evidently accelerated by coral-coral interactions. Page(s): 709-718

Descriptive morphometric analysis of three common bivalve species from Chandipur, Odisha, Eastern India

Fri, 01 Nov 2024 00:00:00 GMT

Title: Descriptive morphometric analysis of three common bivalve species from Chandipur, Odisha, Eastern India Authors: K Kolay, S Abstract: The present study addresses a comprehensive morphometric analysis of three prevalent bivalve species from the Chandipur coast (latitude 21°3' – 21°47' N and longitude 86°02' – 87°20' E), Odisha, India. About 1875 specimens are used in this comprehensive analysis, belonging to the representative species Mactra luzonica Reeve, 1854, Timoclea scabra (Hanley, 1845), and Donax scortum (Linnaeus, 1758) from three different families viz. Mactridae, Veneridae, and Donacidae. The morphometric analysis found strong linear correlations between shell length (L), height (H), and width (W) with statistical significance at p < 0.01, however, the correlation between body size and thickness is weak. Further analysis of morphometric indices, including elongation (H/L), narrowness (W/L), and flatness (W/H) for each species, revealed moderate variations for D. scortum and T. scabra, while the variations were more profound in M. luzonica. An analysis of body shape (L/H) reveals D. scortum being more elliptical (L/H: 1.5 to 2.0) and T. scabra being more oval (L/H < 1.5), while M. luzonica has almost equal distributions in both shapes. This morphological variation is attributed to various ecological stresses as well as habitat conditions. The data provided here can further aid in research related to ecology and conservation of these valuable marine resources. Page(s): 719-728

New distribution record of Honeycomb Sabellaria miryaensis Parab & Gaikwad, 1990 (Polychaeta: Sabellariidae) from the Eastern coast of India, with the first-time report of the genus along the Odisha coast, Bay of Bengal

Fri, 01 Nov 2024 00:00:00 GMT

Title: New distribution record of Honeycomb Sabellaria miryaensis Parab & Gaikwad, 1990 (Polychaeta: Sabellariidae) from the Eastern coast of India, with the first-time report of the genus along the Odisha coast, Bay of Bengal Authors: Pradhan, J; K Behera, R; K Mohapatra, S; Balakrishnan, S Abstract: In the paper, a taxonomic account of the honeycomb, Sabellaria miryaensis Parab & Gaikwad, 1990, is provided based on specimens collected during a daily routine local survey from the Gopalpur coast, Odisha, Bay of Bengal. The species of honeycomb worm was identified based on the morphological characters of the body and paleae structure. The species was formerly described from the Jakimirya, Ratnagiri, West Coast, but this present study represents the distributional record to the east coast of India. Page(s): 729-733