Mesophotic coral ecosystems (MCEs) host a thriving community of biota that has remained virtually unexplored. Here we report for the first time on a large population of the endangered coral species Euphyllia paradivisa from the MCEs of the Gulf of Eilat/Aqaba (GOE/A), Red Sea. The mesophotic zone in some parts of the study site harbors a specialized coral community predominantly comprising E. paradivisa (73 % of the total coral cover), distributed from 36 to 72 m depth. Here we sought to elucidate the strict distribution but high abundance of E. paradivisa in the MCEs at the GOE/A. We present 4 yr of observations and experiments that provide insight into the physiological plasticity of E. paradivisa: its low mortality rates at high light intensities, high competitive abilities, successful symbiont adaptation to the shallow-water environment, and tolerance to bleaching conditions or survival during prolonged bleaching. Despite its ability to survive under high irradiance in shallow water, E. paradivisa is not found in the shallow reef of the GOE/A. We suggest several factors that may explain the high abundance and exclusivity of E. paradivisa in the MCE: its heterotrophic capabilities; its high competition abilities; the possibility of it finding a deep-reef refuge there from fish predation; and its concomitant adaptation to this environment.
|Number of pages||12|
|State||Published - 1 Mar 2016|
Bibliographical noteFunding Information:
We would like to thank the Interuniversity Institute for Marine Sciences for making their facilities available to us. We are grateful to N. Paz for proofreading, Y. Shaked and O. Ben-Shaprut for diving assistance, and all of YL’s lab members for their support. GE was supported by the Israel Taxonomy Initiative (ITI) and Sciences Based Management (SBM) Doctoral Fellowships. This research was partially funded by the Israel Science Foundation (ISF) Grant No. 341/12 and USAID/MERC Grant No. M32-037 to YL.
© 2015, Springer-Verlag Berlin Heidelberg.
- Deep-reef refugia hypothesis (DRRH)
- Mesophotic coral ecosystems (MCEs)
- US Endangered Species Act