Cruise inventory

FRV Scotia 1413S Leg2

Cruise plan

Cruise Info. 
Ship name (ship code)FRV Scotia (748S)
Cruise identifier1413S Leg2
Cruise period2013-10-29 — 2013-11-05
StatusCompleted
Port of departureUllapool, United Kingdom
Port of returnAberdeen, United Kingdom
PurposeFisheries
ObjectivesObjectives

1. Carry out paired, 'bagged' comparative trawls (n = 20 pairs = 40 hauls) with and without the tickler chain to assess the effect on by-catch of skate and ray species.
2. Tag and release Common Skate with electronic data storage tags for studies of their movement.
3. Collect fin clip sample from Common Skate for genetic analyses of population structure.
4. Map seabed in the Stanton Banks area using Swathe MBES

Procedure

Scotia will work the area around the Stanton Banks south of Barra. Allowing a day's steam from Ullapool to the Stanton Banks and a day to get back to Aberdeen, 6 full days and nights are expected. Fishing operations will be generally carried out during daytime and MBES mapping will at night.

Trawling will be carried out at stations between depths of 100-200 m in areas where Common skate have been caught in the past. Some known trawling positions will be covered; other new tows may need to be sourced. At each station a pair of tows will be sequentially made in parallel approximately 0.5 km apart, one tow will be made with the tickler chain on and one with it off (the order will be randomized). The trawl will be fitted with 3 ground-gear bags that will catch fish that escape underneath the rockhoppers. The aim is to quantify not just what is caught by the main net, but also what would have escaped. Four separate catches for each haul will need to be quantified. Trawl duration will be 30 minutes. All skate and ray species will be identified, weighed and measured. In addition, commercial species including cod, saithe, haddock, monk and megrim will be weighed and measured. Any additional sampling will take place concurrently.

Large Common skate in good condition will be measured, tagged and released. Electronic data storage tags (n = 29) will be attached externally. All common Skate will have small piece of dorsal fin removed and placed in ethanol for genetic analyses.

MBES survey will take place at night. The target areas have been defined according to requirements set out by JNCC and will be between depths of 60-180m. Normal contacts will be maintained with the laboratory.
Chief scientistFrancis C Neat (Marine Scotland Aberdeen Marine Laboratory)
Ocean/sea areas 
GeneralNorth East Atlantic Ocean (limit 40W)
SpecificStanton Banks
Track chartsFRV Scotia 1413S Leg2 cruise track — 1413strk.pdf (00 MB)