Resources

FRV Scotia 0411S

Cruise plan

Cruise Info. 
Ship name (ship code)FRV Scotia (748S)
Cruise identifier0411S
Cruise period2011-04-06 — 2011-05-03
StatusCompleted
Port of departureAberdeen, United Kingdom
Port of returnAberdeen, United Kingdom
PurposeFisheries
ObjectivesObjectives

1. To undertake a nationally co-ordinated demersal trawling survey of anglerfish.
2. To undertake counts of anglerfish and determine coral density using the Seatronics TV chariot.
3. To undertake counts of anglerfish (using the Seatronics TV chariot) in two areas regarded as unsuitable for towing the fishing trawl.
4. To obtain temperature and salinity profiles at each trawling station.

Procedures

This is a nationally co-ordinated trawl survey to estimate the abundance and distribution of anglerfish. The survey follows a set of protocols drawn up by an industry science survey-planning group made up of Marine Scotland scientists and fishing representatives. These protocols share much in common with the sampling regimes described in Marine Scotland's standing instructions for demersal trawl surveys.

Trawling

One haul of 60 minutes duration will be made at each sampling station; trawling operations will occur in waters up to a maximum of 1000 m. Daily start times for survey stations undertaken on Part 1 at the Rockall sea area will be at approximately 0700 and continue until approximately 1900. Fishing operations on Part 2 of this survey, on grounds to the west of Scotland and the North sea, will require 24 hrs fishing capability with scientific staff being split into two 12 hour watch periods. The Scanmar system will be used to monitor wingspread, door spread and distance covered during each haul. A bottom contact sensor will be mounted on the footrope to record the distance of the trawl off the seabed.

Catches will be worked up according to the protocols for the anglerfish surveys, which are similar in principle to Marine Scotland's standing instructions.

TV operation

The Seatronics TV chariot will be deployed to check for the presence of coral on trawl sampling sites where coral may potentially be present (as defined by WGDEC potential closed areas). In the event that coral are present, trawling sites will be moved by approximately one nautical mile and the ground will be inspected again. Outside of these deployments, and in due consideration of staff working hours, the TV sled will be operated between the hours of 1900 and 0700 each night, weather permitting, at sites where coral and or hard ground occurs and at sites were trawl samples will be or have been taken. The objective in these deployments will be to count anglerfish and to determine coral density. In these cases, the chariot will sample for a time as required by the operators. The vessel must be at the location of the next new trawl station at 0600 the following morning.

On travelling to and from the survey area, the Seatronics TV chariot will be deployed to undertake counts of anglerfish on grounds deemed unsuitable for fishing. These positions will be conveyed to the vessel prior to sailing but will be in the regions of NW Scotland and west of the Hebrides.

Hydrography & Acoustics

A CTD will be deployed on the trawl at each station. The ships thermosalinograph will be operated throughout the cruise. The ships EK60 scientific echosounder will be operated throughout the cruise to investigate the relationship between ground type and anglerfish distribution.
Chief scientistCraig G Davis (Marine Scotland Aberdeen Marine Laboratory)
Cruise programmeFRV Scotia 0411S cruise programme 0411s.pdf  (0.15 MB) 
Ocean/sea areas 
GeneralNorth Sea
Inner Seas off the West Coast of Scotland
North East Atlantic Ocean (limit 40W)
SpecificScottish coast. Rockall.
Track chartsFRV Scotia 0411S cruise track — 0411strk.pdf (0.18 MB)