Cruz Igor C S, Loiola Miguel, Albuquerque Tiago, Reis Rodrigo, Nunes José de Anchieta C C, Reimer James D, Mizuyama Masaru, Kikuchi Ruy K P, Creed Joel C
Programa de Pós Graduação em Ecologia, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Laboratório Recifes de Corais e Mudanças Globais, Instituto de Geociências, Universidade Federal da Bahia, Salvador, BA, Brazil; Laboratório de Ecologia Marinha Bêntica, Departamento de Ecologia, Instituto de Biologia Roberto Alcântara Gomes, Universidade do Estado do Rio de Janeiro-UERJ, PHLC Sala 220, Rio de Janeiro, RJ, Brazil.
Laboratório Recifes de Corais e Mudanças Globais, Instituto de Geociências, Universidade Federal da Bahia, Salvador, BA, Brazil; Programa de Pós Graduação em Ecologia e Biomonitoramento, Universidade Federal da Bahia, Salvador, BA, Brazil.
PLoS One. 2015 Jan 28;10(1):e0116944. doi: 10.1371/journal.pone.0116944. eCollection 2015.
Consequences of reef phase shifts on fish communities remain poorly understood. Studies on the causes, effects and consequences of phase shifts on reef fish communities have only been considered for coral-to-macroalgae shifts. Therefore, there is a large information gap regarding the consequences of novel phase shifts and how these kinds of phase shifts impact on fish assemblages. This study aimed to compare the fish assemblages on reefs under normal conditions (relatively high cover of corals) to those which have shifted to a dominance of the zoantharian Palythoa cf. variabilis on coral reefs in Todos os Santos Bay (TSB), Brazilian eastern coast. We examined eight reefs, where we estimated cover of corals and P. cf. variabilis and coral reef fish richness, abundance and body size. Fish richness differed significantly between normal reefs (48 species) and phase-shift reefs (38 species), a 20% reduction in species. However there was no difference in fish abundance between normal and phase shift reefs. One fish species, Chaetodon striatus, was significantly less abundant on normal reefs. The differences in fish assemblages between different reef phases was due to differences in trophic groups of fish; on normal reefs carnivorous fishes were more abundant, while on phase shift reefs mobile invertivores dominated.
珊瑚礁相移对鱼类群落的影响仍知之甚少。关于相移对珊瑚礁鱼类群落的成因、影响和后果的研究仅考虑了从珊瑚向大型藻类的转变。因此，关于新型相移的后果以及这些相移如何影响鱼类组合，存在很大的信息空白。本研究旨在比较正常条件下（珊瑚覆盖率相对较高）的珊瑚礁与巴西东海岸托多斯奥斯桑托斯湾（TSB）珊瑚礁上已转变为以多变拟软珊瑚（Palythoa cf. variabilis）为主导的珊瑚礁上的鱼类组合。我们调查了八个珊瑚礁，估计了珊瑚和多变拟软珊瑚的覆盖率以及珊瑚礁鱼类的丰富度、丰度和体型。正常珊瑚礁（48种）和相移珊瑚礁（38种）的鱼类丰富度差异显著，物种减少了20%。然而，正常珊瑚礁和相移珊瑚礁的鱼类丰度没有差异。一种鱼类，横纹蝴蝶鱼（Chaetodon striatus），在正常珊瑚礁上的丰度显著较低。不同珊瑚礁阶段鱼类组合的差异是由于鱼类营养类群的差异；在正常珊瑚礁上，肉食性鱼类更为丰富，而在相移珊瑚礁上，移动性食虫动物占主导地位。
