The influence of crab burrows on sediment salinity in a Rhizophora-dominated mangrove forest in North Brazil during the dry season
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Many ecological processes are influenced by salinity. Burrowing crabs, abundant fauna of mangrove forests around the world, can facilitate sediment water fluxes, which may decrease the salinity in mangrove sediments. We investigated whether and how crab burrow density and secondary fine root biomass interact to drive sediment salinity during the dry season in a northern Brazilian mangrove forest. Areas with high density of Rhizophora mangle prop roots and areas free of such roots were compared. We found no correlation between burrow density and sediment salinity in areas with dense prop and fine roots, while crab density correlated negatively with sediment salinity in areas without prop roots, where fine root density was low. Hence, the strength of sediment desalination effects of crabs seems to be context dependent, and high root density of a salt-excluding mangrove species (R. mangle) seems to counteract the crabs’ effect. Our results complement those of a former study conducted in the same area during the rainy season, highlighting that the findings are independent from seasonality and should be considered when evaluating the overall ecological effects of crabs in mangrove ecosystems.
KeywordsRhizophora mangle Mangrove Ucides cordatus Sediment salinity
The authors would like to thank the University of Pará (UFPA), and Dr. Moirah Menezes and Dr. Ulf Mehlig for the support during the field work. The authors would also like to thank Dr. Thiago Branquinho de Queiroz from the Universidade Federal do ABC (São Paulo) for all support provided. Karen Diele received funding from the MASTS pooling initiative (The Marine Alliance for Science and Technology for Scotland), and its support is gratefully acknowledged. MASTS is funded by the Scottish Funding Council (Grant Reference HR09011) and contributing institutions.
- Acheampong, E., 2001. Distribution of macrozoobenthos abundance and biomass in intertidal soft sediments of North-East Brazil. Master Thesis of the University of Bremen, Germany: 69.Google Scholar
- Crane, J., 1975. Fiddler Crabs of the World: Genus Uca. Princeton University Press, Ocypididae. ISBN 0-691-08102-6.Google Scholar
- Diele, K. 2000. Life history and population structure of the exploited mangrove crab Ucides cordatus cordatus (L.) (Decapoda: Brachyura) in the Caeté Estuary, North Brazil. Bremen, ZMT (Center For Marine Tropical Ecology), Contribution 9: 103.Google Scholar
- Diele, K., V. Koch, F. A. Abrunhosa, J. de Farias Lima & D. de Jesus de Brito Simith, 2010. The Brachyuran Crab Community of the Caeté Estuary, North Brazil: species richness, zonation and abundance. In Mangrove Dynamics and Management in North Brazil, Ecological Studies 211, chapter 16: 251–263. DOI 10.1007/978-3-642-13457-9_16.
- Goes, P., J. O. Branco, M. A. A. Pinheiro, E. Barberi, D. Costa & L. L. Fernandes, 2010. Bioecology of the uçá-crab, Ucides cordatus (Linnaeus, 1763), in Vitória Bay, Espírito Santo State, Brazil. Brazilian Journal of Oceanography 58: 153–163. ISSN 1982-436X.Google Scholar
- Gomes, V. J. C., P. T. A. Feitas & N. E. Asp, 2013. Dynamics and seasonality of the middle sector of a microtidal estuary. In Conley D.C., G. Masselink, P. E. Russell & T. J. O’Hare (eds), Proceedings 12th International Coastal Symposium (Plymount, England), Journal of Costal Research, Special Issue No. 65: 1140–1145. ISSN 0749-0208.Google Scholar
- INMET, 2015. Instituto Nacional de Meteorologia [available on internet at www.inmet.org.br]. Access on 10th of June, 2015.
- Korting, J., 2012. Bioturbation activities of the mangrove crab Ucides cordatus – Method development and first quantification in the Caeté estuary, Pará, Brazil. Master Thesis presented to the University of Bremen, Faculty for Biology & Chemistry.Google Scholar
- Legat, J. F. A., R. L. Mota, A. Puchnick, C. Bittencourt & W. S. Santana, 2006. Considerations about Ucides cordatus cordatus fishing in the Parnaiba River Delta Region, Brazil. Journal of Coastal Research, SI 39 (Proceedings of the 8th International Coastal Symposium): 1281–1283. Itajai, SC, Brazil. ISSN 0749-0208.Google Scholar
- Miller, D. C., 1961. The feeding mechanism of fiddler crabs, with ecological considerations of feeding adaptations. Zoologica 46: 89–101.Google Scholar
- Moura, D. E., C. C. Lamparelli, F. O. Rodrigues & R. C. Vicent, 1998. Decomposição de folhas em manguezais na região de Bertioga, São Paulo, Brasil. Anais do IV Simpósio de Ecossistemas Brasileiros, Águas de Lindóia 1: 130–148.Google Scholar
- Nascimento, D. M., R. R. N. Alves, R. R. D. Barboza, A. J. Schmidt, K. Diele & J. S. Mourão, 2017. Commercial relationships between intermediaries and harvesters of the mangrove crab Ucides cordatus (Linnaeus, 1763) in the Mamanguape River estuary, Brazil, and their socio-ecological implications. Ecological Economics 131: 44–51.CrossRefGoogle Scholar
- Ostrensky, A., U. S. Sternhain, E. Brun, F. X. Wegbecher & D. Pestana, 1995. Análise da viabilidade técnico-econômica dos cultivos do caranguejo-uçá Ucides cordatus (Linnaeus, 1763) no litoral paranaense. Arquivos de Biologia e Tecnologia 38(3): 939–947.Google Scholar
- Pinheiro, J.C., D.M. Bates, S. DebRoy, D. Sarkar & R Core Team, 2012. nlme: linear and nonlinear mixed effects models.Google Scholar
- Pinheiro, M. A. A. & G. Y. Hattori, 2006. Relative Growth of the Mangrove Crab Ucides cordatus (Linnaeus, 1763) (Crustacea, Brachyura, Ocypodidae) at Iguape, São Paulo, Brazil. Brazilian Archives of Biology and Technology 49: 813–823. ISSN 1516-8913.Google Scholar
- R Development Core Team, 2008. R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. ISBN 3-900051-07-0, URL http://www.R-project.org.
- Reise, A. 2003. Estimates of biomass and productivity in fringe mangroves of North-Brazil. PhD Thesis of the Faculty of Biology and Chemistry of the University of Bremen, Germany. ZMT-Contribution 16. ISSN 0944-0143.Google Scholar
- Schmidt, A. J., C. E. Bemvenuti & K. Diele, 2013. Sobre a definição da zona de Apicum e sua impotância ecológica para a população de Caranguejo-Uçá Ucides cordatus (Linnaeus, 1763). Boletim Técnico Científico. CEPENE, Tamandaré – PE – Vol. 19, No. 1: 9–25.Google Scholar
- Twilley, R. R., S. C. Snedaker, A. Yánez-Arancibia & E. Medina, 1995. Mangroves systems. In Global Biodiversity Assessment, Biodiversity and Ecosystem Function: Ecosystem Analysis. Cambridge University Press, Cambridge: 387–393.Google Scholar