The Skeleton Eroding Band Disease on Coral Reefs of Aqaba, Red Sea

Abstract

The occurrence and distribution of the coral disease Skeleton Eroding Band (SEB) has been studied at the Jordanian coast in the Gulf of Aqaba, the northernmost extension of the Red Sea. The SEB syndrome is caused by the colonial, heterotrich ciliate Halofolliculina corallasia: an advancing front of these protists destroys polyps, coenosarc, and surface of the coenosteum. In recent years SEB was registered in reefs of Australia, Mauritius, and the Red Sea. Along the Jordanian coast, disease frequency at four study sites was investigated and afflicted coral genera and species were documented. The study sites were MSS (Marine Science Station)-north, MSS-south, the tourist area near the middle of the coast, and the industrial area adjacent to the Saudi Arabian border. Corals and infections were counted inside randomly placed 1 m 2 frames in reef flats and in 5, 10, and 15 m depths. In order of increasing affectedness of sample sites, MSS-south was the healthiest (12%, 4%, 4%, 16% of infected corals from shallow to deep), followed by MSS-north (19%, 28%, 24%, 24%), the tourist area (51%, 23%, 16%, 41%), and the industrial area (14%, 30%, 39%, 31%). By far the most frequently encountered coral species were Acropora spp. and Stylophora sp., while relative infection-rates were highest among Seriatopora sp. (75%), as well as Stylophora sp., Hydnophora sp., and Galaxea sp. (50% each). This was followed in steadily decreasing order from 44% to 5% by Pocillopora, Mycedium,

A mechanism of transmission and factors affecting coral susceptibility to Halofolliculina sp. infection

“…In the Indo-Pacific, SEB is more prevalent than any other coral disease (Page and Willis 2008) and is more common in polluted and warmer waters (Antonius and Lipscomb 2001;Willis etal. 2004;Winkler et al 2004). In contrast, the prevalence of the Caribbean ciliates appears to be higher in oceanic versus coastal human-influenced reefs (Croquer et al 2006a).…”

“…For example, skeletal eroding band (SEB) syndrome is related to a species of ciliate in the genus Halofolliculina, which affects corals in the Indo-Pacific and the Red Sea (Willis et al 2004;Winkler et al 2004;Page and Willis 2008). SEB had not, however, been reported in the Caribbean (Antonius andLipscomb 2001) until recently, when Croquer et al (2006a, b) found a folliculinid ciliate interacting with over 25 scleractinian coral species.…”

“…Moreover, ciliates from both regions have a lorica and a free-living phase that moves toward the living tissue, penetrates it, and attaches itself to the coral skeleton as the front rapidly advances (Antonius and Lipscomb 2001;Croquer et al 2006b). The susceptibility of corals to SEB in the IndoPacific has been correlated with depth, pollution, and temperature (Willis et al 2004;Winkler et al 2004). In the Indo-Pacific, SEB is more prevalent than any other coral disease (Page and Willis 2008) and is more common in polluted and warmer waters (Antonius and Lipscomb 2001;Willis etal.…”

Distribution, host range and large-scale spatial variability in black band disease prevalence on the Great Barrier Reef, Australia

“…It is possible that corals infected with BBD are more vulnerable to invasion by other pathogens at sites of tissue necrosis along the disease front. Conversely, it is also possible that initial BBD infections may be dependant on a previous injury (Antonius 1981a(Antonius ,b, 1985a, infection with another disease (Antonius 1977, 1981b, Winkler et al 2004 or compromised colony health. It is not possible to distinguish whether the co-occurrence of BBD and bleaching suggests that bleaching plays a role in the initiation or progress of BBD infection or vice versa.…”

Folliculinid ciliates: a new threat to Caribbean corals?

“…Nonetheless, most coral diseases show a narrow distribution and occur within specific geographic regions only. For instance, the yellow band syndrome, white plague type II and dark spots are restricted to the Caribbean (Weil 2004), while other syndromes such as pink spots, porites ulcerative white spot disease, bacterial bleaching, brown band (BrB) and skeletal eroding band (SEB) have only been reported for the Indo-Pacific (Willis et al 2004) and the Red Sea (Winkler et al 2004). Even the few syndromes that are common to different bioregions appear to have a different etiology.…”