FFS Walther Herwig III 439

Cruise summary report

Cruise Info. 
Ship name (ship code)FFS Walther Herwig III (06NI)
Cruise identifier439
Cruise period2020-09-14 — 2020-09-28
Port of departureBremerhaven, Germany
Port of returnBremerhaven, Germany
ObjectivesThe cruise is part of the German contribution to the international herring larvae surveys in the North Sea (IHLS). These surveys are conducted during the autumn and winter herring spawning activity. The ICES coordinated studies monitor the spatial distribution and abundance of herring larvae on an annual basis. Survey results give information about herring spawning stock biomass and the contribution of different spawning components on the overall hatching success. The results provide valuable information for herring stock assessment and the fixation of fishing quotas.

The spatial distribution of herring larvae was found to be in common pattern. Most larvae hatched east of the Orkneys and on shallower banks in the Buchan area. The overall abundance in the Orkney/Shetland area was relatively low compared to previous years. However, conclusions for North Sea herring spawning stock dynamics can only be drawn when information of larvae abundance from all spawning areas become available prior to the herring assessment working group meeting in March 2021.
Chief scientistNobert Rohlf (Thünen Institute of Sea Fisheries, Bremerhaven)
ProjectICES International Herring Larvae Survey
Coordinating bodyInternational Council for the Exploration of the Sea (ICES)
Cruise reportFFS Walther Herwig III 439 cruise report waltherherwigiii_439.pdf (6.82 MB) 
NPRCFFS Walther Herwig III 439 NPRC waltherherwigiii_439.pdf (0.37 MB) 
Ocean/sea areas 
GeneralNorth Sea
SpecificNorthern North Sea, around Orkney and in the Buchan area (ICES Area IVa and IVb)
Track chartsFFS Walther Herwig III 439 cruise track — waltherherwigiii_439trk.pdf (0.15 MB) 
Physical oceanography 
CTD stationsQuantity: number of profiles = 161
Description: Towed CTD
Biology and fisheries 
Eggs and larvaeQuantity: number of hauls = 161
Description: plankton and fish larvae catches