Biological and environmental rhythms in (dark) deep-sea hydrothermal ecosystems
- 1Ifremer, Centre de Bretagne, REM/EEP, Laboratoire Environnement Profond, Plouzané, 29280, France
- 2Département de Sciences Biologiques, Université de Montréal, P.O. Box 6128, Succursale Centre-ville, Montréal, H3C 3J7, Québec, Canada
- 3Ifremer, Centre de Bretagne, REM/RDT, Laboratoire Détection, Capteurs et Mesures, Plouzané, 29280, France
- acurrent address: Mare – Marine and Environmental Sciences Centre, Department of Oceanography and Fisheries, Rua Professor Frederico Machado 4, Horta, 9901-862, Portugal
Abstract. During 2011, two deep-sea observatories focusing on hydrothermal vent ecology were up and running in the Atlantic (Eiffel Tower, Lucky Strike vent field) and the Northeast Pacific Ocean (NEP) (Grotto, Main Endeavour Field). Both ecological modules recorded imagery and environmental variables jointly for a time span of 23 days (7–30 October 2011) and environmental variables for up to 9 months (October 2011–June 2012). Community dynamics were assessed based on imagery analysis and rhythms in temporal variation for both fauna and environment were revealed. Tidal rhythms were found to be at play in the two settings and were most visible in temperature and tubeworm appearances (at NEP). A ∼ 6 h lag in tidal rhythm occurrence was observed between Pacific and Atlantic hydrothermal vents, which corresponds to the geographical distance and time delay between the two sites.