Biopapua / Off Mambare Bay
08 October 2010
We continue our journey along New Guinea and work off Mambare Bay. This bay, into which large rivers finish their course, is bordered by a large reef.
We work off of this reef. Above 500 m, the slope is quite steep and substrates are hard. We must use our dredge. Below, we find mud and plant substrates.
We finish the day by dragging a trawl at 1000 m depth, and retrieve a large piece of wood colonized by many organisms. Among other things, we find a limpet of the genus Pectinodonta . This specimen is particularly interesting, because our recent studies, based on material collected during previous cruises, suggest that the different species of this genus have a limited bathymetric distribution.
Thus, in some areas, different species are present but do not coexist because they do not inhabit the same depths.
We seek to document the geographic and bathymetric distribution of these species. When we retrace the genealogical history of these species, the biogeographic data are important, as they can shed light on the mechanisms responsible for the differentiation and evolution of species.
At this last station we also sampled some organisms typically found at deeper depths, such as this fish.