ADSR - Azores Deep-Sea Research

CRUISES / Terceira 2020

RV Pelagia cruise 64PE479: Terceira Island 2020

Summary Show more ↓

The continuation of the long-lasting collaboration with scientists from the Royal Netherlands Institute for Sea Research (NIOZ). This was the third time deep-sea scientists from IMAR Instituto do Mar and Okeanos University of the Azores joined Fleur Visser cruises. The RV Pelagia cruise 64PE479 aimed to continue exploring the deep-sea areas of the Azores EEZ, namely in the southern Terceira island slopes and deep ridges, to (i) characterize benthic communities inhabiting seamounts in the Azores, such as São Jorge de Fora seamount, (ii) identify new areas that fit the FAO Vulnerable Marine Ecosystem criteria; and (iii) to contribute with additional data to address patterns and drivers of the distribution of deep-sea benthic biodiversity in the Azores region.

Statistics

Transits

120 km

Multibeam Bathymetry

0 km²

Filmed Seabed

0 km

Visited Areas

Stations

Dives

Video Footage Recorded

7 hours

Used Storage

2.93 Tb

Samples

No information available at this moment

Highlights

Video transects enabled documentation of the deep-sea bottom communities and habitat characteristics on a deep ridge south of Terceira island between 1000 – 1500 m. This data will help improve the understanding of the deep-sea benthic communities in the Azores below 1000m depth.
Several coral species not previously observed appeared throughout the dive, generally in low numbers, such as octocorals (e.g., cf. Metallogorgia melanotrichos), black corals (e.g., cf. Bathypathes patula) and bamboo corals from the Isididae family, still to be identified.
In some of the vertical overhangs, the diversity of coral and sponge species increased, and relevant communities formed by black corals, some small plexauridae and glass sponges were observed.
One of the common features observed throughout the deep ridge was the accumulation of what seemed to be old deposits of coral rubble, which in several locations covered the whole seafloor. The origin of this coral rubble has not yet been determined, but it is likely that relates to old communities of scleractinian corals, which were likely more common in the Azores than nowadays.