Cruise inventory

FRV Scotia 1307S_2

Cruise summary report

Cruise Info. 
Ship name (ship code)FRV Scotia (748S)
Cruise identifier1307S_2
Cruise period2007-09-20 — 2007-09-28
StatusCompleted
Port of departureKillybegs, Ireland
Port of returnAberdeen, United Kingdom
PurposeFisheries
ObjectivesShelf edge and seamount deepwater survey

Objectives

1. To map the composition, distribution and abundance of continental slope species including anglerfish (Lophius spp.) on the deepwater slope west of the Hebrides and undertake trawl surveys of the Rosemary bank and Anton Dohrn Seamount.
2. To carry out comparative fishing hauls with the Celtic Explorer.
3. To identify, quantify and record all benthic invertebrate species caught.
4. To collect information at temperature at depth during use of a data storage tag attached to the trawl headline.
5. To investigate the occurrence of Nephrops on the upper shelf slope using TV systems.
6. To undertake TV drop-frame surveys for purposes of habitat mapping on seamounts in the area.
7. To collect biological samples and digital images for key species from both slope and seamount to investigate the possibility of isolated and distinct seamount communities.

Narrative

Scotia delayed sailing from Killibegs, Ireland on the 20 September for approximately 12 hours while a replacement hydraulic pipe was made and fitted. At 1830 Scotia departed and set a course for comparative fishing area 4 on shelf slope. The swell was too heavy for sledge TV Nephrops operations to be undertaken. Fishing operations were underway by 0650 the next morning. Three hauls were made at 1500, 1000 and 500m depths. Of note was a significant catch (54 kg) of large orange roughy (Hoplestethus atlanticus) at 1500m. The 1000 m tow was fouled by a lost trawl net which took some hours to clear. The haul was however considered valid as the scanmar sensors suggested fouling happened late in the tow. That night the TV sledge was deployed, but limited to 2 stations as the sea state became increasingly unfavourable. Fishing operations on 22 September focused on an area south of the Hebridean Terrace seamount with 3 hauls being successfully completed in 1500, 1000 and 500 m depths. Worsening weather that evening meant TV operations were suspended that night. Force 9 winds the following morning meant all scientific operations were suspended and Scotia was forced to dodge. An improvement by 1200 allowed fishing operations to recommence at 500m, although this tow had to be hauled early due to interference by a French fishing vessel. Conditions worsened again with a building swell and Scotia made overnight passage north to the next set of stations. Fishing began at 05.30 hrs on the morning of the 24 September with 2 tows at 1000 and 2 tows at 1500m completed. Winds again increased overnight making it unsuitable for TV Nephrops survey work. Fishing operations on the morning of the 25 September were suspended until 1200 due to force 9 northerly winds. In the afternoon and evening tows at 500, 1000, and 1500 m were completed. This marked the completion of all core time series stations of the survey. Due to the days lost due to poor weather and hydraulic failure there was no opportunity to survey the Anton Dohrn seamount as intended. Instead passage was made to Rosemary Bank and fishing operation commenced on the morning of the 26 September. Three tows at 900, 800 and 600m (repeat tows of the 0607S survey) were completed. Of note was the large catch of spawning Coryphaenoides rupestris at 900 m and 50 kg of Sebastes mentella at 600m. For the remainder of the day the TV drop-frame was utilised for habitat mapping of the seamount. This resulted in valuable footage of various seabed types including outcrops of bedrock. Entanglement with long-line fishing gear meant that operations were curtailed slightly early and were unable to be resumed due to cable damage. At 2300 Scotia began passage to Aberdeen, docking at 0600 hrs on the morning of the 28 September where equipment was offloaded.
Chief scientistFrancis C Neat (Fisheries Research Services Aberdeen Marine Laboratory)
ProjectMF01TA
Coordinating bodyFRS
Cruise reportFRV Scotia 1307S_2 cruise report 1307s.pdf — access key 'C' (0.57 MB) 
Ocean/sea areas 
GeneralNorth East Atlantic Ocean (limit 40W)
SpecificShelf edge West of Scotland and Ireland, Rosemary Bank
Track chartsFRV Scotia 1307S_2 cruise track — 1307s_2trk.pdf (00 MB) 
Measurements 
Physical oceanography 
Other physical oceanographic measurementsQuantity: number of hauls = 15
Description: Jackson Deepwater trawls (BT184) for survey work and comparative fishing hauls with Celtic Explorer. Temperature measured using data logger attached to trawl headline.
Biology and fisheries 
Pelagic fishQuantity: number of hauls = 15
Description: Jackson Deepwater trawls (BT184) for survey work and comparative fishing hauls with Celtic Explorer. Temperature measured using data logger attached to trawl headline.
Demersal fishQuantity: number of hauls = 15
Description: Jackson Deepwater trawls (BT184) for survey work and comparative fishing hauls with Celtic Explorer. Temperature measured using data logger attached to trawl headline.
CrustaceansQuantity: number of stations = 2
Description: TV sledge deployments for purposes of Nephrops surveys
Geology and geophysics 
Bottom photographyQuantity: number of surveys = 5
Description: TV drop-frame used for habitat mapping