Corals from the Persian/Arabian Gulf as models for thermotolerant reef-builders: Prevalence of clade C3 Symbiodinium, host fluorescence and ex situ temperature tolerance

• Published in: Marine pollution bulletin Vol. 72; no. 2; pp. 313 - 322
• Main Authors: Hume, B., D’Angelo, C., Burt, J., Baker, A.C., Riegl, B., Wiedenmann, J.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 30.07.2013
• Subjects: Abu Dhabi; Adaptation, Physiological; Animals; Anthozoa - physiology; Bleaching; Coral reefs; corals; Dinoflagellida - physiology; Environmental Monitoring; Fiji; Fluorescence; Global warming; Green fluorescent protein; habitats; Heat stress; heat tolerance; Hot Temperature; Indian Ocean; mortality; Persian Gulf; pigments; sampling; Saudi Arabia; Seawater - chemistry; summer; Symbiodinium; symbionts; Symbiosis; temperature; United Arab Emirates; water pollution; Zooxanthellae; Saudi Arabia; Fiji; United Arab Emirates; Indian Ocean; Persian Gulf; Coral reefs; Global warming; Zooxanthellae; Heat stress; Bleaching; Green fluorescent protein
• ISSN: 0025-326X; 1879-3363; 1879-3363
• DOI: 10.1016/j.marpolbul.2012.11.032

► Prevalence of Symbiodinium clade C3 in heat stress tolerant corals from Abu Dhabi. ► Heat stress regulation of green fluorescent protein (GFP)-like coral pigments. ► Stability of coral-algal symbiosis in Porites lobata. ► Thorough characterisation of P. lobata from the Arabian/Persian Gulf. ► Natural growth rates of Gulf corals in successful laboratory cultures. Corals in the Arabian/Persian Gulf endure summer temperatures of up to 36°C, making them ideal subjects to study the mechanisms underlying thermal tolerance. Unexpectedly, we found the “generalist” Symbiodinium clade C3 to be the prevalent symbiont among seven coral species from Abu Dhabi (UAE) waters. Moreover, C3 represented the only dominant symbiont type in Porites spp. from this region. The “thermotolerant” symbionts D1a and C15 were not encountered, indicating that the association with these symbionts cannot be the sole reason for the heat tolerance of Gulf corals. The association of Porites lobata with specific symbiont types (C3 vs. C15) in samples from habitats with very different temperature regimes (Abu Dhabi vs. Fiji) remained unaffected by laboratory culture. During temperature stress experiments specimens from both locations strongly downregulated green fluorescent protein (GFP)-like pigments. However, the Abu Dhabi samples were less prone to bleaching and showed lower mortality.