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Ecological processes of phase shift to Palythoa grandiflora dominance on reefs of Todos-os-Santos Bay, Brazil.

2016; Frontiers Media; Volume: 3; Linguagem: Inglês

10.3389/conf.fmars.2016.05.00050

2296-7745

Cruz Igor, Ruy Kikuchi, Creed Joel,

Coral and Marine Ecosystems Studies

Event Abstract Back to Event Ecological processes of phase shift to Palythoa grandiflora dominance on reefs of Todos-os-Santos Bay, Brazil. Igor C. Cruz1, 2*, Ruy K. Kikuchi3 and Joel C. Creed2 1 Instituto Oceanográfico da Universidade de São Paulo, Biological Oceanography, Brazil 2 Universidade do Estado do Rio de Janeiro, Departamento de Ecologia, Brazil 3 Universidade Federal da Bahia, Departamento de Oceanografia, Brazil Some coral reefs of Todos-os-Santos Bay have undergone a drastic change in the benthic community. In 2003, they began to be dominated by the zoanthid Palythoa grandiflora. This phenomenon is a consequence of coral reef degradation that now reaches approximately 20% of coral reefs worldwide and threatens another 35%. The most dramatic consequences of this degradation are the phase shift phenomena which are characterized by reduction of coral abundance and increase of organisms that do not build reefs. Despite their importance, only a phase shift to the domain of macroalgae has been sufficiently studied. Given this situation, it is urgent to create functional models that demonstrate the ecological processes that occur in the installation of alternative states that persist over time. These models provide important information that can help in decision making on management measures both for prevention and recovery of these ecosystems. The aims of this work are (i) to verify if this phenomenon is a phase shift, (i.e. the reduction of the abundance of coral and persistence of high coverage P. grandiflora for more than five years of monitoring), (ii) evaluate the effects of competition between this zoanthid and coral with manipulative experiments and (iii) study the effects of dominance on the fish assemblage. The result confirmed the existence of a phase shift, suggesting that the abundance of P. grandiflora increased in 2003 or before and in 2007 there was a reduction in coral cover, and that this condition remained until at least 2013. The three coral species tested show great sensitivity to contact with P. grandiflora, with necrosis in 78% of the colonies and with overgrow in 35% of cases in a period of 118 days. In addition, a model made from the data of a proportion of coral colonies in contact with this zoanthid and coverage of P. grandiflora suggests that when the zoanthid reaches 6% coverage, 50% of coral colonies come in contact with it. These data are strong evidence that the reduction of coral cover observed between 2003 and 2007 was caused by competition between these organisms. It was found that this phase shift reduces species richness of reef fishes, by ten species unless reefs normal, and that favor mobile invertivores to the detriment of carnivores and sessile invertivores. However there was no difference in the abundance of fish. Acknowledgements ICSC acknowledges a PhD scholarship from Conselho Nacional de Pesquisa (CNPq) (No 556755/2010-3) and postdoctoral fellowship from Fundação de Amparo a Pesquisa do Estado de São Paulo (FAPESP) (No. 2014/17815-0). RKPK and JCC benefited from a CNPq fellowship (PQ 1D). JCC acknowledges financial support of the Programade Incentivo a Produçâo Científica, Tecnica e Artística, UERJ and grants from the Fundaçao Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (No. E-25/170669/20 References Connell, J. H., and Sousa, W. P. (1983). On the evidence needed to judge ecological stability or persistence. Am. Nat. 121, 789–824. doi:10.1086/284105. Cruz, I. C. S., Kikuchi, R. K. P., and Creed, J. C. (2014). Improving the construction of functional models of alternative persistent states in coral reefs using insights from ongoing research programs: A discussion paper. Mar. Environ. Res. 97, 1–9. doi:10.1016/j.marenvres.2014.01.003. Cruz, I. C. S., de Kikuchi, R. K. P., Longo, L. L., and Creed, J. C. (2015a). Evidence of a phase shift to Epizoanthus gabrieli Carlgreen, 1951 (Order Zoanthidea) and loss of coral cover on reefs in the Southwest Atlantic. Mar. Ecol. 36, 318–325. doi:10.1111/maec.12141. Cruz, I. C. S., Loiola, M., Albuquerque, T., Reis, R., de Anchieta C. C. Nunes, J., Reimer, J. D., et al. (2015b). Effect of Phase Shift from Corals to Zoantharia on Reef Fish Assemblages. PLoS One 10, e0116944. doi:10.1371/journal.pone.0116944. Cruz, I. C. S., Meira, V. H., de Kikuchi, R. K. P., and Creed, J. C. (2016). The role of competition in the phase shift to dominance of the zoanthid Palythoa cf. variabilis on coral reefs. Mar. Environ. Res. 115, 28–35. doi:10.1016/j.marenvres.2016.01.008. Done, T. J. (1992). Phase shifts in coral reef communities and their ecological significance. Hydrobiologia 247, 121–132. doi:10.1007/BF00008211. Dudgeon, S. R., Aronson, R. B., Bruno, J. F., and Precht, W. F. (2010). Phase shifts and stable states on coral reefs. Mar. Ecol. Prog. Ser. 413, 201–216. doi:10.3354/meps08751. Norström, A. V., Nyström, M., Lokrantz, J., and Folke, C. (2009). Alternative states on coral reefs: beyond coral–macroalgal phase shifts. Mar. Ecol. Prog. Ser. 376, 295–306. doi:10.3354/meps07815. Keywords: regime shift, Alternative state, competition, Benthic Ecology, benthic communities, Functional models Conference: XIX Iberian Symposium on Marine Biology Studies, Porto, Portugal, 5 Sep - 9 Sep, 2016. Presentation Type: Oral Presentation Topic: 1. ECOLOGY, BIODIVERSITY AND VULNERABLE ECOSYSTEMS Citation: Cruz IC, Kikuchi RK and Creed JC (2016). Ecological processes of phase shift to Palythoa grandiflora dominance on reefs of Todos-os-Santos Bay, Brazil.. Front. Mar. Sci. Conference Abstract: XIX Iberian Symposium on Marine Biology Studies. doi: 10.3389/conf.FMARS.2016.05.00050 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers' terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 01 May 2016; Published Online: 02 Sep 2016. * Correspondence: Dr. Igor C Cruz, Instituto Oceanográfico da Universidade de São Paulo, Biological Oceanography, São Paulo, São Paulo, 05508-120, Brazil, igorcruz@usp.br Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Igor C Cruz Ruy K Kikuchi Joel C Creed Google Igor C Cruz Ruy K Kikuchi Joel C Creed Google Scholar Igor C Cruz Ruy K Kikuchi Joel C Creed PubMed Igor C Cruz Ruy K Kikuchi Joel C Creed Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.