title: Spectral Diversity and Regulation of Coral Fluorescence in a Mesophotic Reef Habitat in the Red Sea.
abstract: The phenomenon of coral fluorescence in mesophotic reefs, although well described for shallow waters, remains largely unstudied. We found that representatives of many scleractinian species are brightly fluorescent at depths of 50-60 m at the Interuniversity Institute for Marine Sciences (IUI) reef in Eilat, Israel. Some of these fluorescent species have distribution maxima at mesophotic depths (40-100 m). Several individuals from these depths displayed yellow or orange-red fluorescence, the latter being essentially absent in corals from the shallowest parts of this reef. We demonstrate experimentally that in some cases the production of fluorescent pigments is independent of the exposure to light; while in others, the fluorescence signature is altered or lost when the animals are kept in darkness. Furthermore, we show that green-to-red photoconversion of fluorescent pigments mediated by short-wavelength light can occur also at depths where ultraviolet wavelengths are absent from the underwater light field. Intraspecific colour polymorphisms regarding the colour of the tissue fluorescence, common among shallow water corals, were also observed for mesophotic species. Our results suggest that fluorescent pigments in mesophotic reefs fulfil a distinct biological function and offer promising application potential for coral-reef monitoring and biomedical imaging.
authors.affiliation: Department of Zoology, Tel-Aviv University, Tel-Aviv, Israel; The Interuniversity Institute for Marine Sciences of Eilat, Eilat, Israel.
authors.forename: Gal
authors.initials: G
authors.lastname: Eyal
authors.affiliation: Coral Reef Laboratory, University of Southampton, NOCS, Southampton, United Kingdom; Institute for Life Sciences (IFLS), University of Southampton, Southampton, United Kingdom.
authors.forename: Jörg
authors.initials: J
authors.lastname: Wiedenmann
authors.affiliation: Department of Zoology, Tel-Aviv University, Tel-Aviv, Israel.
authors.forename: Mila
authors.initials: M
authors.lastname: Grinblat
authors.affiliation: Coral Reef Laboratory, University of Southampton, NOCS, Southampton, United Kingdom.
authors.forename: Cecilia
authors.initials: C
authors.lastname: D'Angelo
authors.affiliation: Department of Biotechnology Engineering, Ben-Gurion University, Beer Sheva, Israel.
authors.forename: Esti
authors.initials: E
authors.lastname: Kramarsky-Winter
authors.affiliation: Charney School of Marine Sciences, University of Haifa, Haifa, Israel.
authors.forename: Tali
authors.initials: T
authors.lastname: Treibitz
authors.affiliation: Department of Zoology, Tel-Aviv University, Tel-Aviv, Israel.
authors.forename: Or
authors.initials: O
authors.lastname: Ben-Zvi
authors.affiliation: The Interuniversity Institute for Marine Sciences of Eilat, Eilat, Israel.
authors.forename: Yonathan
authors.initials: Y
authors.lastname: Shaked
authors.affiliation: Center for Marine and Environmental Studies, University of the Virgin Islands, St. Thomas, United States Virgin Islands, United States of America.
authors.forename: Tyler B
authors.initials: TB
authors.lastname: Smith
authors.affiliation: Tropical Biosphere Research Center, University of the Ryukyus, Motobu, Okinawa, Japan.
authors.forename: Saki
authors.initials: S
authors.lastname: Harii
authors.affiliation: Biodiversity Research Center, Academia Sinica, Taipei, Taiwan.
authors.forename: Vianney
authors.initials: V
authors.lastname: Denis
authors.affiliation: Bermuda Institute of Ocean Sciences (BIOS), St. George's, Bermuda.
authors.forename: Tim
authors.initials: T
authors.lastname: Noyes
authors.affiliation: The Interuniversity Institute for Marine Sciences of Eilat, Eilat, Israel; Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel.
authors.forename: Raz
authors.initials: R
authors.lastname: Tamir
authors.affiliation: Department of Zoology, Tel-Aviv University, Tel-Aviv, Israel.
authors.forename: Yossi
authors.initials: Y
authors.lastname: Loya
mesh_terms: D000818:Animals; D037421:Anthozoa / Q000502:physiology* / Q000528:radiation effects; D044822:Biodiversity; D003116:Color; D057894:Coral Reefs; D017753:Ecosystem; D005453:Fluorescence; D019156:Indian Ocean; D007557:Israel; D008027:Light; D010860:Pigments, Biological / Q000096:biosynthesis / Q000737:chemistry*
chemical_list: D010860:Pigments, Biological