Impacts of natural disturbances on the population dynamics of the sea urchin Diadema setosum at Khang Khao Island, the Upper Gulf of Thailand


  • Sittiporn Pengsakun Marine Biodiversity Research Group, Ramkhamhaeng University Marine Biodiversity Research Group Department of Biology, Faculty of Science Ramkhamhaeng University
  • Anirut Klomjit Marine Biodiversity Research Group, Department of Biology, Faculty of Science, Ramkhamhaeng University
  • Makamas Sutthacheep Marine Biodiversity Research Group, Department of Biology, Faculty of Science, Ramkhamhaeng University
  • Thamasak Yeemin Marine Biodiversity Research Group, Department of Biology, Faculty of Science, Ramkhamhaeng University
  • Charernmee Chamchoy Marine Biodiversity Research Group, Department of Biology, Faculty of Science, Ramkhamhaeng University
  • Wasana Phantewee


Population dynamics, Diadema setosum, Khang Khao Island, Bioerosion


The sea urchin, Diadema setosum, is a dominant species commonly found in coral communities in the Upper Gulf Thailand. It plays a major role in the bioerosion of coral reefs by feeding on epilithic algae, enabling coral settlement and growth. This research aims to study the population dynamics of the sea urchin D. setosum and the change of bioerosion rates at Khang Khao Island, Chonburi Province. Field surveys were conducted during 1998 - 2016 using belt transect method (50m x 1m). The results revealed that population densities of D. setosum varied among years (One-way ANOVA, p<0.05). The highest density was found in 2009 (11.34 ind/m2), while the lowest density was detected in 2011 (4.02 ind/m2) because of the impact of strong freshwater runoffs, followed by a recovery in 2012.The average bioerosion rates observed in 1998 (1.05±0.33kg CaCO3/m2/year) were significantly lower than that observed in 2016 (2.55±1.07kg CaCO3/m2/year) (t-test, p<0.01) reflecting that the higher bioerosion rate is related to an increased sea urchin’s population, as well as body size. This study provides baseline data on population dynamics of D. setosum in relation to reef bioerosion as a proxy for the management of coral reef ecosytems.


Bak RPM (1990) Patterns of echinoid bioerosion in two Pacific coral reef lagoons. Marine Ecology Progress Series 66:267–272

Bak RPM (1994) Sea urchin bioerosion on coral reefs: place in the carbonate budget and relevant variables. Coral Reefs 13:99–103

Bronstein O, Kroh A, Loya Y (2016) Reproduction of the long-spined sea urchin Diadema setosum in the Gulf of Aqaba - implications for the use of gonad-indexes. Scientific Reports 6:29569

Bronstein O, Loya Y (2014) Echinoid community structure and rates of herbivory and bioerosion on exposed and sheltered reefs. Journal of Experimental Marine Biology and Ecology 456:8–17

Carreiro-Silva M, TR McClanahan (2001) Echinoid bioerosion and herbivory on Kenyan coral reefs: the role of protection from fishing. Journal of Experimental Marine Biology and Ecology 262:133–153

Conand C, Chabanet P, Cuet P, Letourneur Y (1997) The carbonate budget of a fringing reef inLa Réunion Island (Indian Ocean): sea urchin and fish bioerosion and net calcification. Proceeding 8th International Coral Reef Symposium. Smithsonian Tropical Research Institute, Balboa, pp 953–958

Coppard SE, Campbell AC (2007) Grazing preferences of diadematid echinoids in Fiji. Aquatic Botany 86:204–212

Dumas P, Kulbicki M, Chifflet S, Fichez R, Ferraris J (2007) Environmental factors influencing urchin spatial distributions on disturbed coral reefs (New Caledonia, South Pacific). Journal of Experimental Marine Biology and Ecology 344:88–100

Dumont CP, Lau DCC, Astudillo JC, Fong KF, Chak STC, Qiu JW (2013) Coral bioerosion by the sea urchin Diadema setosum in Hong Kong: Susceptibility of different coral species. Journal of Experimental Marine Biology and Ecology 441:71–79

Edinger EN, Jompa J, Limmon GV, Widjatmoko W, Risk MJ (1998) Reef degradation and coral biodiversity in Indonesia: effects of land-based pollution, destructive fishing practices and changes over time. Marine Pollution Bulletin 36(8):617-630

Graham NAJ, Nash KL (2013) The importance of structural complexity in coral reef ecosystems. Coral Reefs 32:315–326

Glynn PW (1979) Coral reef growth in the Galapagos: limitation by sea urchins. Science 203:47–49

Glynn PW, Manzello DP (2015) Bioerosion and Coral Reef Growth: A Dynamic Balance. In: Birkeland C. (eds) Coral Reefs in the Anthropocene. Springer, Dordrecht

Heron SF, Eakin CM, Douvere F (2017) Impacts of Climate Change on World Heritage Coral Reefs : A First Global Scientific Assessment. Paris, UNESCO World Heritage Centre.

Jones GP, McCormick MI, Srinivasan M, Eagle JV (2004) Coral decline threatens fish biodiversity in marine reserves. Proceedings of the National Academy of Sciences 101:8251-8253

Lirman D (2001) Competition between macroalgae and corals: effects of herbivore exclusion and increased algal biomass on coral survivorship and growth. Coral Reefs 19:392–399

Lirman D and Schopmeyer S (2016) Ecological solutions to reef degradation: optimizing coral reef restoration in the Caribbean and Western Atlantic. PeerJ DOI: 10.7717/peerj.2597

McClanahan TR, Nugues M, Mwachirey S (1994) Fish and sea urchin herbivory and competition in Kenyan coral reef lagoons: the role of reef management. Journal of Experimental Marine Biology and Ecology 184:237–254

McClanahan TR, Polunin N, Done T (2002) Ecological states and the resilience of coral reefs. Conservation Ecology 6(2):18

Ortiz JC, Wolff NH, Anthony KRN, Devlin M, Lewis S, Mumby PJ (2018) Impaired recovery of the Great Barrier Reef under cumulative stress. Science Advance DOI: 10.1126/sciadv.aar6127

O’Leary JK, Potts D, Schoenrock KM, McClahanan TR (2013) Fish and sea urchin grazing opens settlement space equally but urchins reduce survival of coral recruits. Marine Ecology Progress Series 493:165–177

Pearson RG (1981) Recovery and recolonization of coral reefs. Marine Ecology Progress Series 4:105–122

Peyrot-Clausade M, Chabanet P, Conand C, Fontaine MF, Letourneur Y, Harmelin-Vivien M (2000) Sea urchin and fish bioerosion on la réunion and moorea reefs. Bulletin of Marine Science 66:477–485

Sakai K, Snidvong A, Yeemin T, Nishihira M, Yamazato K (1986) Distribution and community structure of hermatypic corals in the Sichang Islands, inner part of the Gulf of Thailand. Galaxea 5:27–74

Sangmanee K, Sutthacheep M, Yeemin T (2012) The decline of the sea urchin Diadema setosum affected by multiple disturbances in the inner Gulf of Thailand. Proceedings of the 12th International Coral Reef Symposium: The boom and bust of urchins and starfish. Cairns, Australia

Sutthacheep M, Sakai K, Yeemin T, Pengsakun S, Klinthong W, Samsuvan W (2018) Assessing coral reef resilience to climate change in Thailand. Ramkhamhaeng International Journal of Science and Technology 1:22-34

Tsuchiya M, Lirdwitayaprasit T (1986) Distribution of intertidal animals on rocky shores of the Sichang Islands, the Gulf of Thailand. Galaxea 5:15-25

Yeemin T, Saenghaisuk C, Sutthacheep M, Pengsakun S, Klinthong W, Saengmanee K (2009) Conditions of coral communities in the Gulf of Thailand: a decade after the 1998 severe bleaching event. Galaxea 11:207–217






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