Resources

RRS Discovery DY099

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS Discovery (74EQ)
Cruise identifierDY099
Cruise period2019-02-16 — 2019-03-08
StatusCompleted
Port of departureStanley, Falkland Islands (Malvinas)
Port of returnStanley, Falkland Islands (Malvinas)
PurposeResearch
ObjectivesBlue Belt: Benthic biodiversity of the South Sandwich Islands

In 2012 the Government of South Georgia & the South Sandwich Islands (GSGSSI) declared a sustainable use Marine Protected Area across more than 1 million km2 of the Scotia Sea within its maritime zone (MZ), which was further enhanced in 2013 and 2019. The GSGSSI MPA monitoring, and development requires scientific information that will describe the benthic ecological processes in several key sites; including the data poor area around the South Sandwich Islands. Consequently, in 2019 Cefas, chartered the RRS Discovery to undertake a survey around the South Sandwich Islands examining the biodiversity and distribution of benthic invertebrate species and their potential vulnerability to impacts of the licensed longline research fisheries. The Blue Belt programme also took the opportunity to reach out to other academic UK research teams, with less access to resources, by sharing the capabilities of that the Discovery offers as a research platform. Cefas therefore teamed up with colleagues from the Universities of Essex, Bristol and Oxford during the expedition.

At each survey location a representative area incorporating a bathymetric range of ∼150–2,000 m was covered by one or more acoustic survey lines collecting MBES bathymetry and backscatter. A preliminary analysis of the bathymetry onboard the vessel was used to inform the placement of target stations for drop camera deployment, of approximately 30 min seabed time, with the aim of targeting ∼200, 500, 750, 1,000, and 1,500 m depths.

Five islands along the South Sandwich Islands archipelago were sampled. At each island, a deep-water camera system and benthic trawls were used to survey epifaunal species distribution and diversity from 200m to 2,200m. The survey focused on determining trends in species distribution and diversity across both latitudinal and depth gradients to analyse the influence of topography and environment on benthic fauna species and community structure.
Chief scientistChristopher Darby (Centre for Environment, Fisheries and Aquaculture Science Lowestoft Laboratory), Paul McIlwaine (Centre for Environment, Fisheries and Aquaculture Science Lowestoft Laboratory)
ProjectBlue Belt: Benthic biodiversity of the South Sandwich Islands
Cruise reportRRS Discovery DY099 cruise report dy099_research.pdf (20.82 MB)  RRS Discovery DY099 cruise report dy099_survey.pdf (1.50 MB) 
Ocean/sea areas 
GeneralSouthern Ocean
Unknown
SpecificSouth Georgia and South Sandwich Islands Marine Protected Area (SGSSI MPA)
Measurements 
Biology and fisheries 
ZoobenthosQuantity: number of specimens = 500
Description: Over 500 specimens were collected from six stations at four survey areas in the South Sandwich Island chain from a total of ten successful hauls from 12 deployments (four dredge and eight Agassiz trawls).
Mammals and reptilesQuantity: activity duration in hours = 67
Description: Observers undertook a total of 67 hours of marine mammal observations, covering a total of 1,486km (803 nautical miles). A total of 567 marine mammals were counted during these observations.
Demersal fishQuantity: number of specimens = 500
Description: Over 500 specimens were collected from six stations at four survey areas in the South Sandwich Island chain from a total of ten successful hauls from 12 deployments (four dredge and eight Agassiz trawls).
Geology and geophysics 
DredgeQuantity: number of specimens = 500
Description: Over 500 specimens were collected from six stations at four survey areas in the South Sandwich Island chain from a total of ten successful hauls from 12 deployments (four dredge and eight Agassiz trawls).
Bottom photographyQuantity: number of images = 4124
Description: Seabed imagery: Seabed imagery was acquired from a total of 36 stations and six survey areas during 38 deployments.4124 images were acquired during the collection of 30 hours and 10 minutes of video footage.
Single-beam echosoundingQuantity: activity duration in days = 22
Description: Acoustic data throughout the survey transit and from areas of interest.
Multi-beam echosoundingQuantity: activity duration in days = 22
Description: Acoustic data throughout the survey transit and from areas of interest.