Resources

FFS Walther Herwig III 364

Cruise summary report

Cruise Info. 
Ship name (ship code)FFS Walther Herwig III (06NI)
Cruise identifier364
Cruise period2013-03-20 — 2013-04-25
StatusCompleted
Port of departureBremerhaven, Germany
Port of returnBremerhaven, Germany
PurposeResearch
ObjectivesICES-coordinated international study in the Eastern North Atlantic. The main objective is to produce both an index and a direct estimate of the biomass of the Northeast Atlantic mackerel stock and the southern and western horse mackerel stocks. The general method is to quantify the freshly spawned eggs in the water column on the spawning grounds. To be able to establish a relationship between eggs and spawning stock biomass, the fecundity of the females must also be determined. This is done by sampling sufficient numbers of gonads before, during and after spawning. These samples are then histologically analysed. In combination, the realised fecundity (potential fecundity minus atresia) of the females and the actual number of freshly spawned eggs in the water render an estimate of the spawning stock biomass. To provide a reliable estimate of the quantity of spawned eggs and the fecundity, an extensive coverage of the spawning area is required both in time and space.
Chief scientistJens Ulleweit (Thünen Institute of Sea Fisheries, Hamburg)
ProjectInternational Mackerel and Horse Mackerel Egg Survey 2013
Coordinating bodyInternational Council for the Exploration of the Sea (ICES)
Cruise reportFFS Walther Herwig III 364 cruise report waltherherwigiii_364.pdf (1.37 MB) 
Ocean/sea areas 
GeneralCeltic Sea
Bay of Biscay
North East Atlantic Ocean (limit 40W)
SpecificWest of Ireland, Celtic Sea, northern Bay of Biscay (between 53.45 N and 48.45N).