SPI-ing on reefs and seamounds

Silvana Birchenough from Cefas continues to report on the SPI work conducted during the expedition.......
Nearly time to return home and I am delighted to report that our SPI camera has been a great success. We have been able to take some fantastic images of the fauna at the Mingulay Reef, Banana Reef and Logachev mounds study sites. This has included taking images down to a depth of 1000m at Logachev. Most of our previous SPI work and collection of images have been taken at 35-45 m depth. This is the first time SPI images have been taken in these areas, which make it very interesting for us to see in real time some of the fauna and sediment types. This expedition has been really interesting for us on all fronts. We have been able to use different equipment, survey at different depths and develop of a series of experiments, which will help to expand our current understanding on the effects of ocean acidification.

Our SPI work will also provide some very interesting ecological information for some of the study sites. The ability to study in-situ fauna and their activities across different habitat types adjacent to the cold water corals areas is a real bonus. Our SPI images have been collected as a series of ~1.5 to 2 km transects. We were able to target specific areas since we had multibeam data available to support our transect designs.

We have collected approximately 300 SPI images at the three study sites. The data will keep me busy with the data analysis over the next few months; the results are very interesting and will help us to expand our current knowledge. After an initial review of some of these images I can see there are differences across the sites. They show numerous species of fauna (e.g. sponges, polychaete tubes, squat lobsters, brittle stars and coral) and biogenic structures (e.g. burrows, feeding voids, redox layers and sediment types) in the habitats located around the Lophelia pertusa reefs. We hope to use this information to help understand the existing biodiversity and function (e.g. bioturbation) of the communities adjacent to the cold-water coral reefs.

The Sediment Profile Imagery (SPI) is an in-situ technique, which takes vertical profile pictures of the upper 20 cm of soft sediments. The images can provide clear insight into the relationship between fauna and their habitat. We will be able to integrate these data sets as baseline information to understand the potential effects caused by ocean acidification on these systems.

I have included some of our images, see our results…..