@article {ISI:000354588900002,
	title = {{Sources of organic carbon for Rimicaris hybisae: Tracing individual fatty acids at two hydrothermal vent fields in the Mid-Cayman rise}},
	journal = {DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS},
	volume = {100},
	year = {2015},
	month = {jun},
	pages = {13{\textendash}20},
	type = {Article},
	abstract = {Hydrothermal vents harbor ecosystems mostly decoupled from organic carbon synthesized with the energy of sunlight (photosynthetic carbon source) but fueled instead by oxidation of reduced compounds to generate a chemosynthetic carbon source. Our study aimed to disentangle photosynthetic and chemosynthetic organic carbon sources for the shrimp species Rimicaris hybisae, a primary consumer presumed to obtain its organic carbon mainly from ectosymbiotic chemoautotrophic bacteria living on its gill cover membrane. To provide ectosymbionts with ideal conditions for chemosynthesis, these shrimp live in dense clusters around vent chimneys; they are, however, also found sparsely distributed adjacent to diffuse vent flows, where they might depend on alternative food sources. Densely and sparsely distributed shrimp were sampled and dissected into abdominal tissue and gill cover membrane, covered with ectosymbiotic bacteria, at two hydrothermal vent fields in the Mid-Cayman rise that differ in vent chemistry. Fatty acids (FA) were extracted from shrimp tissues and their carbon isotopic compositions assessed. The FA data indicate that adult R. hybisae predominantly rely on bacteria for their organic carbon needs. Their FA composition is dominated by common bacterial FA of the n7 family (similar to 41{\%}). Bacterial FA of the n4 FA family are also abundant and found to constitute good biomarkers for gill ectosymbionts. Sparsely distributed shrimp contain fractions of n4 FA in gill cover membranes similar to 4{\%} lower than densely packed ones (similar to 18{\%}) and much higher fractions of photosynthetic FA in abdominal tissues, similar to 4{\%} more (compared with 1.6{\%}), suggesting replacement of ectosymbionts along with exoskeletons (molt), while they take up alternative diets of partly photosynthetic organic carbon. Abdominal tissues also contain photosynthetic FA from a second source taken up presumably during an early dispersal phase and still present to c. 3{\%} in adult shrimp. The contribution of photosynthetic carbon to the FA pool of adult R. hybisae is, however, overall small (max. 8{\%}). Significant differences in carbon isotopic values of chemosynthetically derived FA between vent fields suggest that different dominant C fixation pathways are being used. (C) 2015 Published by Elsevier Ltd.},
	keywords = {ROV Jason (Remotely Operated Vehicle)},
	issn = {0967-0637},
	doi = {10.1016/j.dsr.2015.02.003},
	author = {Streit, Kathrin and Bennett, Sarah A and Van Dover, Cindy L and Coleman, Max}
}
@article {Bennett2013,
	title = {{Trophic regions of a hydrothermal plume dispersing away from an ultramafic-hosted vent-system: Von Damm vent-site, Mid-Cayman Rise}},
	journal = {Geochemistry, Geophysics, Geosystems},
	volume = {14},
	number = {2},
	year = {2013},
	pages = {317{\textendash}327},
	abstract = {Deep-sea ultramafic-hosted vent systems have the potential to provide large amounts of metabolic energy to both autotrophic and heterotrophic microorganisms in their dispersing hydrothermal plumes. Such vent-systems release large quantities of hydrogen and methane to the water column, both of which can be exploited by autotrophic microorganisms. Carbon cycling in these hydrothermal plumes may, therefore, have an important influence on open-ocean biogeochemistry. In this study, we investigated an ultramafic-hosted system on the Mid-Cayman Rise, emitting metal-poor and hydrogen sulfide-, methane-, and hydrogen-rich hydrothermal fluids. Total organic carbon concentrations in the plume ranged between 42.1 and 51.1 $μ$M (background = 43.2 {\textpm} 0.7 $μ$M (n = 5)) and near-field plume samples with elevated methane concentrations imply the presence of chemoautotrophic primary production and in particular methanotrophy. In parts of the plume characterized by persistent potential temperature anomalies but lacking elevated methane concentrations, we found elevated organic carbon concentrations of up to 51.1 $μ$M, most likely resulting from the presence of heterotrophic communities, their extracellular products and vent larvae. Elevated carbon concentrations up to 47.4 $μ$M were detected even in far-field plume samples. Within the Von Damm hydrothermal plume, we have used our data to hypothesize a microbial food web in which chemoautotrophy supports a heterotrophic community of microorganisms. Such an active microbial food web would provide a source of labile organic carbon to the deep ocean that should be considered in any future studies evaluating sources and sinks of carbon from hydrothermal venting to the deep ocean.},
	keywords = {ROV Jason (Remotely Operated Vehicle)},
	issn = {1525-2027},
	doi = {10.1002/ggge.20063},
	url = {http://dx.doi.org/10.1002/ggge.20063},
	author = {Bennett, S A and Coleman, Max and Huber, J A and Reddington, E and Kinsey, J C and McIntyre, C and Seewald, J S and German, C R}
}
