RV Cefas Endeavour 10/13
Cruise summary report
|Ship name (ship code)||RV Cefas Endeavour (74E9)|
|Cruise period||2013-06-08 — 2013-06-17|
|Port of departure||Lowestoft, United Kingdom|
|Port of return||Lowestoft, United Kingdom|
|Objectives||For the Farn Deeps the survey design is based on a randomised fixed grid and includes a total of 110 stations. The initial ground perimeter has been delimited by the combination of VMS data and BGS sediment maps. At each station a sledge mounted TV camera was deployed and a clear 10 minute tow was recorded onto DVD and DVT. Vessel position (DGPS) and position of sledge (using a USBL transponder) were recorded every 1 to 2 seconds.
Additionally, complementary information was collected for DP342 project "Better value for money: integration of approaches in support of Nephrops assessments".
Out of 110 stations 90 were selected to do the full coverage with all gears (TV sledge, day grab, SPI and multibeam coverage). The selection of the stations was made in order to use the geostatistical model that has been used to calculate the Nephrops abundance.
In order to map the sediment of the Farn Deeps ground a 0.1 m2 day-grab was used in each station. This device samples an area of 0.1 m2, to a maximum depth of 14 cm.
Rapid Fines Analysis (RFA). The RFA samples were placed in a clear plastic tube (200mm length, 16mm diameter) and 20ml filtered seawater added. Samples were then gently agitated for 20 seconds until completely suspended in the seawater. The tubes were then allowed to settle in a vertical position for 24 hours. Once settling had taken place samples were placed in a light box and photographed using an Olympus Stylus Tough-8000 set at 12 mega pixels; macro on; exposure set to -2.0; and the flash off. Subsequent image analysis of the photos is to be carried out at Cefas Lowestoft in order to estimate %silt/clay particles in the sediment.
Particle Size Analysis (PSA) - to be completed post-cruise
The Sediment Profile Image (SPI) camera was deployed from the side gantry at 90 TVID stations. Images were analysed using ImageJ to estimate sediment type, presence/absence burrows and measure apparent redox potential discontinuity (aRPD).
Swathe data were collected on the survey over the TV stations.
|Chief scientist||Ana M Leocadio (Centre for Environment, Fisheries and Aquaculture Science Lowestoft Laboratory)|
|Cruise report||(1.43 MB)|
|Track charts||(00 MB)|