Fruitful Bough 3309H
|Ship name (ship code)||Fruitful Bough (74I1)|
|Cruise period||2010-01-25 — 2010-02-08|
|Port of departure||Peterhead, United Kingdom|
|Port of return||Peterhead, United Kingdom|
To perform selectivity trials on the following test cases:
1. A "Swedish Grid" with bar spacing of 35 mm rigged in the extension at 15 m from the codline, used in conjunction with an 80 mm diamond mesh codend.
2. A "Swedish Grid" with bar spacing of 40 mm rigged in the extension at 15 m from the codline, used in conjunction with an 80 mm diamond mesh codend.
3. A "Swedish Grid" with bar spacing of 40 mm rigged in the extension at 15 m from the codline, used in conjunction with a 120 mm Square Mesh Panel rigged at 6-9m from the codline and an 80 mm diamond mesh codend.
Staff and equipment will join Fruitful Bough (PD109) at Peterhead on Mon 25 Jan 2010. Staff will then commence rigging the test gears to the vessels nephrops trawls, configuring the scanmar setup, and installing fish and nephrops measuring stations aboard the vessel in Peterhead harbour.
Time permitting the vessel will steam during the afternoon of 25 Jan to fishing grounds relatively close by and carry out a shakedown haul. The vessel will then steam offshore to the Fladen/North Fladen grounds and thereafter selectivity data will be collected for the different test configurations.
Selectivity will be measured by using the twin trawl method. Initially the port trawl (the Control) will sample the total population of fish and nephrops available on the ground using a small (40 mm) mesh codend. The starboard trawl (the Test) will have one of the three experimental gear configurations (above) attached. Catches from the Test will be compared to those from the Control. A swap-over of the relative positions on the twin-rig of the Test and Control will take place half way through the trials.
The main target species will be cod, haddock, whiting, hake, plaice, witch, nephrops and all species of skate. Other species may be additionally targeted as time and conditions permit.
The intention is to change the test configurations every two days to allow for variation in catch composition over the experimental period. A scientific derogation has been obtained permitting fishing without a square mesh panel and use of the small mesh codends. It will also allow the landing any marketable fish, which will be offset against the cost of the charter.
Ship's accommodation will be used throughout the fishing trials. A call at an appropriate port will be made approximately 2-3 February to allow landing of catch. The cruise will end at Fraserburgh/Peterhead on 8* February when staff and equipment will return to Aberdeen.
Normal contacts will be maintained with the Laboratory.
|Chief scientist||James Drewery (Marine Scotland Aberdeen Marine Laboratory)|
|Cruise programme||(0.02 MB)|
|Specific||Fladen/North Fladen grounds|