FRV Explorer 13/80

Cruise summary report

Cruise Info. 
Ship name (ship code)FRV Explorer (74EX)
Cruise identifier13/80
Cruise period1980-11-28 — 1980-12-18
Port of departureAberdeen, United Kingdom
Port of returnAberdeen, United Kingdom
Objectives1) To survey the stocks of spurdogs to the North-West of Scotland
2) To search for mature female spurdogs in varying depth zones and to identify whelping grounds
3) To tag spurdogs
4) To detemine which zones of the water column are frequented by spurdogs
5) To collect data on the feeding and maturity/fecundity of spurdogs
6) A sample of pyloric caeca from herring was collected and preserved for examination at the laboratory for parasite infestations
7) Samples of cod, haddock, whiting, saithe, plaice, scad, anglers, and skate were frozen and returned to the laboratory for mercury analysis

Gale force winds forced ''Explorer'' to shelter in Inganess Bay on the 30/11/1980. New trawl messenger wires were collected in Ullapool. Due to a strong swell and a return to gale force winds, the ship was forced to seek shelter in Copinsay. A half-landing took place in Kirkwell on the 11/12/1980 till the 12/12/1980. Strong westerley gales halted operations and ''Explorer'' was forced to seelk shelter in the lee of the Hebrides.
Chief scientistJ A Gauld (Department of Agriculture and Fisheries for Scotland Aberdeen Marine Laboratory)
Cruise reportFRV Explorer 13/80 cruise report explorer13_80.pdf (1.34 MB) 
Ocean/sea areas 
GeneralNorth Sea
Inner Seas off the West Coast of Scotland
North East Atlantic Ocean (limit 40W)
SpecificW. Scotland, Strathy, E of Orkney, North and South Minch, lee of Longa Island, Cellar Head, Shiant Islands, grounds off Noup, lee of Caithness
Track chartsFRV Explorer 13/80 cruise track — explorer13_80track.pdf (1.14 MB) 
Biology and fisheries 
Demersal fishQuantity: number of stations = 35
Description: Trawling. 826 stomachs were examined
TaggingsQuantity: number of specimens = 1020
Description: spurdogs measured, sexed and double tagged with Swiftattachment nylon flag and Peterson disc tags attached through the bases of the first and second dorsal fins respectively. 100 Scyhorhinus caniculus were tagged with a single Swiftattachment nylon flag attached through the base of the first dorsal fin.