FRV Mara 4/66

Cruise summary report

Cruise Info. 
Ship name (ship code)FRV Mara (74MR)
Cruise identifier4/66
Cruise period1966-04-16 — 1966-05-25
Port of departureBuckie, United Kingdom
Port of returnBuckie, United Kingdom
Objectives1) To study the acoustic properties of fish swim bladders by the analysis of echos and sounds produced by single fish
2) To observe the effects of different rates of decompression on haddock being brought to the surface
3) An attempt was made to determine the optimum rate of ascent to the surface in order to obtain live haddock intact with swim bladders
4) A night dive was carried out in the vicinity of an underwater 200 watt light which had a large aggregation of organisms below it as seen by the ship's echo sounder
5)The routine bottom fauna and hydrographic survey of Loch Linnhe and Loch Eil was carried out
6) Diving observations
Chief scientistColin J Chapman (Department of Agriculture and Fisheries for Scotland Aberdeen Marine Laboratory)
Cruise reportFRV Mara 4/66 cruise report mara4_66.pdf (1.95 MB) 
Ocean/sea areas 
GeneralInner Seas off the West Coast of Scotland
SpecificKyle, approaches to Loch Ainort, Loch Eil, Corpach, Caledonian Canal
Biology and fisheries 
Demersal fishDescription: Cruise was to study properties of fish swim bladders. To look at the rates of decompression on haddock being brough to the surface.
Demersal fishDescription: Fish were held in small cages, suspended in mid water and echoed using low frequency pulsed sound sources. No. of measurements not recorded.
Demersal fishQuantity: activity duration in days = 5
Description: A survey was carried out at Corpach.
Demersal fishDescription: Cages were laid off 'Moll' in the northern approaches to Loch Ainort. No. of hauls not specified.