Main Article Content
Corals constitute a dominant benthic community in the reef areas of the Gulf of Mannar. The decline of hard corals provides space for the dominance of other coral taxa, which helps in stabilizing the degraded reef ecosystems. We documented one such degraded patch reef area with abundant octocoral distribution. This site is located near Periyasamipuram, a coastal village on the mainland (outside Marine National Park). We made a comparative study to assess the significant difference in the distribution of octocorals between the patch reef and the main reef in Kariyachalli Island (inside Marine National Park). The study was conducted from January to March in 2017 and from January to March 2018. This study's underwater visual estimations reveal that the increase in the octocoral cover is significantly different in the patch reef and the island reef. A total of 19 species of octocorals were recorded, representing the families Alcyoniidae, Subergorgiidae, and Ellisellidae. Based on the external morphology and the presence of sclerites (calcareous structures), identification was done down to the possible level. Our preliminary study recorded a maximum of 15.53% of octocoral coverage in the patch reef area and total coverage of 1.51% in the reefs of Kariyachalli Island. Statistical analysis and non-parametric multivariate and univariate scaling reveal the difference in the octocoral distribution between the study sites. Long-term monitoring is required to assess their ecological role and formulate effective conservative reef ecosystem measures.
Gattuso JP, Hoegh-Guldberg O, Pörtner HO. Cross-chapter box on coral reefs, in Climate Change 2014: Impacts, Adaptation, and Vulnerability Part A: Global and Sectoral Aspects Contribution of Working Group II to the Fifth Assessment Report of the Intergovernmental Panel of Climate Change, eds C. B. Field VR, Barros DJ, Dokken KJ, Mach MD, Mastrandrea TE, Bilir, et al. (Cambridge; New York, NY: Cambridge University Press). 2014b;97–100.
HoeghGuldberg O, Cai R, Poloczanska ES, Brewer PG, Sundby S, Hilmi K, et al. The ocean. clim. change 2014 impacts, adapt. vulnerability. part b reg. asp. contrib. work. gr. II to fifth assess. Rep. Intergov. Panel Clim. Change. 2014a ;165:5-1732.
Molberg F, Folke C. Ecological goods and services of coral reef ecosystems. Ecological Economics. 1999;29(2):215-233.
Wild, et al. Climate change impedes scleractinian corals as primary reef ecosystem engineers. Marine and Freshwater Research. 2011;62:205–215.
Pickett STA, White PS. Natural disturbance and patch dynamics: an introduction. In: Pickett STA, White PS (eds) The ecology of natural disturbance and patch dynamics. Academic Press, Orlando. 1985;3–13.
Raijnen BT, Hoeksema BW, van Ofwegen LP, van der Meij SE. Soft corals and sea fans symbioses with Octocorallia studied. In:Duistermaat L and van Tol J (eds) report 2009–2012 Naturalis.Research and Education. 2012;96–97.
Lau YW, Poliseno A, Kushida Y, Quéré G, Reimer JD. The clas-sification, diversity and ecology of shallow water octocorals. In:Goldstein M, DellaSala D (eds) Encyclopedia of the World's bi-omes. Elsevier, Amsterdam. 2019;1–15.
Brock WA, Carpenter SR. Variance as a leading indicator of regime shift in ecosystem services. Ecology and Society. 2006;11:9
Cheal AJ, MacNeil MA, Cripps E, Emslie MJ, Jonker M, Schaffelke B, Sweatman H. Coral–macroalgal phase shifts or reef resilience: Links with diversity and functional roles of herbivorous fishes on the Great Barrier Reef Coral Reefs. 2010;29:1005–1015.
Edward JKP, Mathews G, Patterson J, Ramkumar R, Wilhelmsson J, Tamelander O, et al. Status of coral reefs of the gulf of mannar, southeastern India, Coral Reef Degradation in the Indian Ocean Status (CORDIO). Status Report. (SDMRI: Thoothukudi, India). 2008;45-55.
Balaji (Jr) S, Edward JKP, Samuel VD. Coastal and Marine Biodiversity of Gulf of Mannar, Southeastern India - A comprehensive updated species list. Gulf of Mannar Biosphere Reserve Trust, Publication. 2012;22:128.
Khan SA, Rajendran N, Balasubramanian T. Research need for Gulf of Mannar, GOMBRT Publication. 2006;5:22.
George RM, Jasmine S. Scleractinian coral diversity in Indian reefs, their threats and conservation. CMFRI Publication. 2012; 33-37.
Edward JKP, Mathews G, Jamila Patterson, Dan Wilhelmsson, Jerker Tamelander, Olof Linden. Coral reefs of the Gulf of Mannar, Southeastern India – Distribution, Diversity and Status. SDMRI Special Research Publication. 2007;12:113.
ENVIS Centre. Database on gulf of mannar biosphere reserve, Department of Environment, Government of Tamil Nadu, Chennai. 2015;15:37.
Kumar PD, Edward JKP. Status of Path reef resource diversity in PeriyaPar, Tuticorin coast of Gulf of Mannar, Southeatern India Perspectives on Biodiversity of India. 2014;II:1.
Edward JKP, Mathews G, Raj KD, Thinesh T, Patterson J, Wilhelmsson TD. Coral reefs of Gulf of Mannar, India – signs of resilience. In ‘Proceedings of the 12th International Coral Reef Symposium, 7-11 July 2008, Cairns, Australia; 2012.
Edward JKP, Mathews G, Raj KD, Laju RL, Bharath MS, Arasamuthu A, et al. Severe coral bleaching in the gulf of mannar, Southeastern India: A Status Update. Reef Encounter. 2017;31(1):65-68.
Chadwick NE, Morrow KM. Competition among Sessile organisms on coral reefs. In Coral Reefs: An Ecosystem in Transition. (Eds Z. Dubinsky, N. Stambler). (Springer, Dordrecht). 2011;347-371.
Aronson RB, Precht WF. White-band disease and the changing face of Caribbean coral reefs. Hydrobiologia. 2001b;460:25–38.
Bayer P, Rybach L, Blum P, Brauchler R. Review on life cycle environmental effects of geothermal power generation. Renew. Sust. Energy Rev. 2013;26:446–463.
Fabricius KE, Klumpp D. Widespread mixotrophy in reef-inhabiting soft corals: The influence of depth, and colony expansion and contraction on photosynthesis. Marine Ecology Progression Series. 1995;125:195–204.
Seah JZS, Yap NWL, Tan LT, Goh BPL. Distribution and abundance of octocoral (Octocorallia, alcyonacea) communities at three Southern Islands of Singapore. Ocean Science Journal. 2015;50:299.
Lenz EA, Bramanti L, Lasker H, Edmunds P. Long-term variation of octocoral population in St. John, US Virgin Islands. Coral reefs. 2015;34(4):1099-1109.
Blois JL, Williams JW, Fitzpatrick MC, Jackson ST, Ferrier S. Space can substitute for time in predicting climate-change effects on biodiversity. In ‘Proceedings of the National Academy of Sciences of the United States of America. 2013;110:9374–9379.
Hickson SJ. The Alcyonaria of Maldives. Pt. III. The families Muriceidae, Gorgonethidae, Melitodidae and the genera Pannatula and Eunephthea. In: the fauna and geography of the Maldive and Laccadive Archipelagoes. Gardiner SJ. (ed.), 1905;2(4):807-826.
Hickson SJ. Coelenterata I.--Alcyonaria. National Antarctic (Discovery) Expedition, Nat. Hist., pl. 1. British Museum. 1907;3:l-15.
Pratt EM. Report on some alcyoniidae collected by Prof. Herdman at Ceylon in 1902. Report to the Government of Ceylon on the Pearl and Oyster Fisheries of the Gulf of Mannar. 1905;3:247-68.
Thomson JA, Henderson WD. An account of the alcyonarians collected by the Royal Indian Marine Survey Ship Investigator in the Indian Ocean. Part 1. The Alcyonarians of the deep sea. Calcutta: The Indian Museum. 1906;1-10: i-xvi + 1132.
Thomson JA, Simpson JJ. An account of the alcyonarians collected by the Royal Indian marine survey ship Investigator in the Indian Ocean. II. The alcyonarians of the littoral area. Trustees of the Indian Museum, Calcutta. 1909;2:1-319,
Van Ofwegen LP, Vennam J. Notes on Octocorallia from the laccadives (SW India). Zool. Meded. (Leiden). 1991;65:143-54.
Alderslade P, Shirwaiker P. New species of soft corals (Coelenterata: Octocorallia) from the Laccadive Archipelago. Beagle: Records of the Museums and Art Galleries of the Northern Territory, The. 1991;8:189
Jayasree V, Parulekar AH. The ecology and distribution of Alcyonaceans at Mandapam (Palk Bay, Gulf of Mannar), South India. 1997;94: 521–524.
Rani Mary G, Sanil NK, Naomi TS. A qualitative appraisal of the soft corals (Octocorallia: Alcyonacea) off Mandapam, South India. Indian J. Fish. 2007;54(1):99-106.
Mary AG, Sluka RD. Biodiversity and distribution of octocorals of Minicoy atoll, Lakshadweep. Atoll Research Bulletin; 2014.
Sivaleela G, Padmanaban. Studies on the Alcyonacean fauna of Gulf of Mannar. 2015;115: 21–30.
English SE, Wilkinson C, Baker V. Survey manual for tropical marine resources. (Australian Institute of Marine Science, Townsville, Australia); 1997.
Fabricius KE, Alderslade P. Soft Corals and Sea Fans: A comprehensive guide to the tropical shallow water genera of the central-west Pacific, the Indian Ocean and the Red Sea. (Australian Institute of Marine Science, Townsville). 2001;264.
Clarke KR, Gorley RN. PRIMER V.6: User manual/tutorial. PRIMER-E, Plymouth; 2006.
Verseveldt J. A revision of the genus Sinularia May (Octocorallia, Alcyonacea). Verhandelingen Leiden. 2001,1980;179:l-128.
Dudgeon S, Aronson RB, Bruno JF, Precht WF. Phase shifts and stable states on coral reefs. Marine Ecology Progress Series. 2010;413:201-216.
Aronson RB, Precht WF. Evolutionary paleoecology of Caribbean coral reefs. in Allmon WD, Bottjer DJ, editors. Evolutionary paleoecology. Columbia University Press, New York, New York, USA. 2001a;171–201.
Aronson RB, Precht WF. White-band disease and the changing face of Caribbean coral reefs. Hydrobiologia. 2001b;460:25–38.
Bruno JF, Sweatman H, Precht WF, Selig ER, Schutte VGW. Assessing evidence of phase shifts from coral to macroalgal dominance on coral reefs. Ecology. 2009;90:1478–1484.
McManus JW, Polsenberg JF. Coral– algal phase shiftson coral reefs: Ecological and environmental aspects. Prog Oceanogr. 2004;60:263–279.
Ashok AM, Schönberg CHL, Raj KD, Bhoopathi M, Bharath MS, Patterson EJK. A sponge os the Cliona viridis complex invades and excavates corals of the Gulf of Mannar, south-eastern India. Marine and Freshwater Research. 2018;69:874–882.
Benayahu Y, Jeng MS, Finkel SP, Dai CF. Soft Corals (Octocorallia: Alcyonacea) from southern Taiwan. II. Species diversity and distributional Patterns. Zoological Studies. 2004;43(3):548-560.
Baum G, Januar I, Ferse SCA, Wild C, Kunzmann A. Abundance and physiology of dominant soft corals linked to water quality in Jakarta Bay, Indonesia. Peer J. 2016; 4:e2625.
Barre SL, Coll JC. Movement in soft corals: An interaction between Nephthea brassica (Coelenterata: Octocorallia) and Acropora hyacinthus (Coelenterata: Scleractinia). Marine Biology. 1982;72:119-124.
Benayahu Y, Loya Y. Settlement and recruitment of a soft coral: Why is Xenia macrospiculata a successful colonizer?. Bulletin of Marine Science. 1985;36(1):177-188.
Raj KD, Mathews G, Edward JKP. Macroalgal assemblage structure on the reefs of Tuticorin group in the Gulf of Mannar. Journal of Marine Biological Association of India. 2006;48(2):166-172.
Maida M, Sammarco PW, Coll JC. Effects of soft corals on scleractinian coral recruitment. ii: allelopathy, spat survivorship and reef community structure. Marine Ecology. 2002;22(4):397-414.
Reinicke GB, van Ofwegen LP. Soft corals (Alcyonacea: Octocorallia) from shallow water in the Chagos Archipelago: species assemblages and their distribution. In ‘Ecology of the Chagos Archipelago’. (Eds C. R. C. Sheppard, M. R. D Seaward). (Linn Soc Occasional Pub, 2). 1999;67–85.
Norström AV, Nyström M, Lokrantz J, Folke C. Alternative states on coral reefs: Beyond coral– macroalgal phase shifts. Marine Ecology Progress Series. 2009;376:295–306.
McFadden CS, Ofwegen LPV, Beckman EJ, Benayahu Y, Alderslade P. Molecular systematics of the speciose Indo-Pacific soft coral genus, Sinularia (Anthozoa: Octocorallia). Invertebrate Biology. 2009;128(4):303–323.
Grigg RW. Recruitment limitation of a deep benthic hard-bottom octocoral population in the Hawaiian Islands. Marine Ecology Progression Series. 1988;45:121-126.
Jokiel PL, Rodgers KS, Brown EK, Kenyon JC, Aeby G, Smith WR, et al. Comparison of methods used to estimate coral cover in the Hawaiian Islands. Peer J. 2015;3:e954.
Edinger, E. N., and Risk, M. J. (2000). Reef classification by coral morphology predicts coral reef conservation value. Biological Conservation, Elsevier, 92, 1-13.
Samuel D, Sivaramakrishnan T, Mathews G, Edward JKP. Threats to coral reefs of Gulf of Mannar Marine National Park In: Coral reefs in India - status, threats and conservation measures. eds. by Bhatt, J.R., Edward, J.K.P, Macintosh D.J. and Nilaratna, B.P., IUCN India. 2012;265-271.
Kumar KM. Studies on floral diversity of Tuticorin coastal environment, southeast coast of India. PhD Thesis, Manonmaniam Sundarnar University; 2015.
Fabricius KE. Reef invasion by soft corals: Which taxa and which habitats?. In ‘Proceedings of the Australian Coral Reef Society 75th Anniversary Conference’, Heron Island October 1997. (Eds J. G. Greenwood, N. J. Hall), (University of Queensland, Brisbane, Qld, Australia). 1998;77–90.
Whalan S, Abdul Wahab MA, Sprungala S, Poole AJ, de Nys R. Larval Settlement: The Role of Surface Topography for Sessile Coral Reef Invertebrates. PLoS ONE. 2015;10(2): e0117675.