The Great Meteor Seamount (Northeast Atlantic): stepping stone or trapping stone? Quantitative investigations of the distribution, diversity, and origin of the Harpacticoida (Crustacea, Copepoda) of the seamount summit

• Applicant: Dr. Kai Horst George
• Subject Area: Ecology and Biodiversity of Animals and Ecosystems, Organismic Interactions ; Systematics and Morphology (Zoology)
• Term: from 2013 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 233694656

In the frame of a thorough project aiming to investigate the possible role of seamounts for the dispersal of marine meiobenthos, and to contribute towards clearing the so-called meiofauna paradox, the here applied project focuses on quantitative taxonomic and multivariate community analyses of the Harpacticoida (Crustacea, Copepoda) from the plateau of the Great Meteor Seamount (GMS). Previous investigations were based on qualitative sampling material only to treat questions as to a possible role as stepping stone of GMS for the dispersal of meiofauna, or whether the hydrographic and geographic isolation of that seamount instead lead to the development of unique harpacticoid assemblages. According to several authors, the latter assumption seems to be more plausible. However, as the underlying sampling material has a limited significance only, in particular because it was sampled using different gears, research cruise P397 of RV POSEIDON to the GMS in 2010 enabled for the first time an area-wide and comprehensive sampling of meiofauna. Twenty-one grid-like positioned locations were sampled quantitatively on the plateau. Evaluation of the sampling material shall provide meaningful data of the distribution of Harpacticoida on the GMS plateau. Moreover, the relation between scientifically known and unknown species will be estimated; this may allow recognizing if a continuous immigration of species from other regions does occur, or if harpacticoid arrivals on the GMS plateau may be rather singular and accidental. Indication for the latter should be a comparatively high portion of scientifically unknown species, pointing at the same time to a pronounced endemism. Also a relatively high part of closely related but distinct species might support the assumption of an isolated and unique harpacticoid fauna on GMS that evolved via radiation of accidentally arrived species; as there is no frequent immigration of potential competitors, plateau species are able to realize new ecological niches even in areas (shelves, littoral) where they would not have any chance because of too high pressure of competition.Furthermore the hypothesis of a harpacticoid plateau fauna as mainly descending from deep-sea relatives (emergence) shall be proved; former studies found corresponding indications, while on other seamounts a clear dominance of shallow-water species was detected.Beyond a faunistisc comparison it is aimed to compare the obtained data with those from other seamounts (Sedlo, Seine) and ith the island of Madeira. New species shall be described and made therewith accessible for further biological studies. It is expected that the here applied project may contribute fundamentally to our knowledge of the dispersal of Harpacticoida in the northeast Atlantic.

• DFG Programme: Research Grants