Sunday, July 18, 2010

Flemish Cap Complete

The last dive on Flemish Cap was certainly not the least. This one dive held what taxonomists believe to be 2 entirely new species of cold-water corals (right). After struggling to reach the bottom because of the strong deep-ocean currents in this area, ROPOS took a few critical samples and began the arduous 12 hr journey up the slope towards the top of the cap. This dive spanned almost 1200 m of water depth from beginning to end and displayed a vast array of habitats, ranging from cliff side terraces lined with complex glass sponges and never before seen coral species to sandy bottoms which were comparatively devoid of life. The dive finished strong at 1300 m by providing scientists on board with a view of spectacularly dense beds of large white sponges of the family Geodiidae. Closure areas implemented by NAFO in this area were based on by-catch records of this habitat forming sponge (left). For more images from this dive click here (FCP6).

Despite weather and emergency delays in schedule, the dives on Flemish Cap have proven successful. These dives have given researches a glimpse into the deep waters of the slope ringing the Flemish Cap. Taxonomic samples have provided voucher specimens for video analysis that will take place once on shore. Incidentally, these collections have lead to some exciting discoveries; including 11 possibly new species and many more rarely encountered organisms. Geological samples collected and habitat classification conducted on board during dives in Flemish Cap will provide some insight into the geological origins of the cap while simultaneously enhancing our understanding of the driving factors affecting the distribution of deep-sea organisms in the area.

As well, 2 dives were specifically focused on surveying key portions of recent NAFO closure areas. The first of these dives on Flemish Cap successfully investigated the impact of trawling gear on vulnerable marine species. The data generated by transects run through both trawled and un-trawled ocean bottom within the footprint of an EU trawl survey conducted in the area in 2007, will provide researchers with some indication of the sustained legacy that trawling may have on deep-sea sponges and corals and other associated organisms. The second closure area dive was particularly interesting as it provided a glimpse into an undisturbed world of habitat forming sponges. Data from this dive will be used to modify existing models of sponge distribution and will assist in describing the species associated with these important biological features.

We are currently making the 9 hr steam north to begin a series of dives at Orphan Knoll. Shawn Meredyk, a Memorial University student conducting a Masters of Science Degree in Environmental Science specializing in the surficial geology and marine biology of Orphan Knoll, will provide a summary of activities for the first dive at this never before visited location.

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