Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6387616 | Marine Environmental Research | 2016 | 31 Pages |
Abstract
Phase shift phenomena are becoming increasingly common. However, they are also opportunities to better understand how communities are structured. In Southwest Atlantic coral reefs, a shift to the zoanthid Palythoa cf. variabilis dominance has been described. To test if competition drove this process, we carried out a manipulative experiment with three coral species. To estimate the natural frequency of encounters we assess the relationship between the proportion of encounters and this zoanthids coverage. The contact causes necrosis in 78% of coral colonies (6.47 ± SD 7.92 cm2) in 118 days. We found a logarithmic relationship between the proportion of these encounters and the cover of P. cf. variabilis, where 5.5% coverage of this zoanthid is enough to put 50% of coral colonies in contact, increasing their partial mortality. We demonstrate that zoanthid coverage increase followed by coral mortality increase will reduce coral cover and that competition drives the phase shift process.
Keywords
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Oceanography
Authors
Igor Cristino Silva Cruz, Verena Henschen Meira, Ruy Kenji Papa de Kikuchi, Joel Christopher Creed,