title: Secondary production of the fiddler crab Uca rapax from mangrove areas under anthropogenic eutrophication in the Western Atlantic, Brazil.
abstract: Fiddler crabs Uca rapax were analyzed in three mangrove areas located in both a lagoon and estuarine system in order to study the influence of eutrophication on their population dynamics and production. Populations at the three sites showed a biased sex ratio. Densities were similar at the three sites, but biomass was higher at the lagoon system. Despite biomass being higher at the most eutrophic site, this site exhibited the lowest production. Regarding age structure, the population inhabiting the less eutrophic site mainly comprised younger crabs. The lower production and smaller P/B ratio found in the more eutrophic site were most likely consequences of a high mortality rate and an aged population. Our study evidences the high plasticity of the fiddler crab U. rapax, and confirms secondary production and P/B ratio estimates as useful tools to assess the effects of environmental change.
authors.affiliation: Departamento de Biologia Marinha, Universidade Federal Fluminense, P.O. Box 100.644, 24001-970 Niterói, RJ, Brazil; CE3C - Centre for Ecology, Evolution and Environmental Changes/Azorean Biodiversity Group and Universidade dos Açores, Departamento de Biologia, Ponta Delgada, Açores, Portugal. Electronic address: tarsommc@gmail.com.
authors.forename: Tarso de M M
authors.initials: Tde M
authors.lastname: Costa
authors.affiliation: Departamento de Biologia Marinha, Universidade Federal Fluminense, P.O. Box 100.644, 24001-970 Niterói, RJ, Brazil.
authors.forename: Abilio
authors.initials: A
authors.lastname: Soares-Gomes
mesh_terms: D000818:Animals; D018533:Biomass; D003386:Brachyura / Q000502:physiology*; D001938:Brazil; D004777:Environment; D005068:Eutrophication; D005260:Female; D008297:Male; D011156:Population Density; D012744:Sex Ratio; D053833:Wetlands
keywords: Biomass; Energy flow; Food web; Population dynamics; Productivity