FFS Walther Herwig III 391
Cruise summary report
|Ship name (ship code)||FFS Walther Herwig III (06NI)|
|Cruise period||2016-01-04 — 2016-01-18|
|Port of departure||Bremerhaven, Germany|
|Port of return||Bremerhaven, Germany|
|Objectives||The German Small-scale Bottom Trawl Survey (GSBTS) continued the long-term investigation of winter bottom fish assemblages through sampling of the standard area "Box A" in the German Bight. The mean catch yielded per half hour trawl duration (143 kg) was well in line with the long term mean. A striking amount of spotted dogfish (Scyliorhinus canicula) was obser ved in this year's survey (0.7 kg/30 min.). As a contradiction to the increasing trend seen in most recent years, the striped red mullet (Mullus surmuletus) was nearly absent.
Within the 10-by-10 nautical mile area in the Box, the GOV bottom trawls were accompanied by monitoring of the benthic epifauna with a 2-m beam trawl. The epifauna in Box A was generally dominated by high numbers of the starfish Asterias rubens, the solenette Buglossidium luteum and the bivalve Nucula nitidosa. In contrast, high abundances of the brittle star Ophiura ophiura and the masked crab Corystes cassivelaunus disappeared.
The international herring larvae surveys in the North Sea (IHLS) are conducted annually during the autumn and winter herring spawning activity and monitor the spatial distribution and abundance of herring larvae. The survey index is used as an important estimator of herring spawning stock biomass and provides valuable information for herring stock assessment and the fixation of fishing quotas. Quantities of newly hatched larvae were much lower compared to the historic high estimates found in the English Channel in 2014 and 2013. However, conclusions for North Sea herring stock spawning biomass 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 2016.
|Chief scientist||Nobert Rohlf (Thünen Institute of Sea Fisheries, Hamburg)|
|Project||ICES International Herring Larvae Survey|
|Coordinating body||International Council for the Exploration of the Sea (ICES)|
|Cruise report||(0.30 MB)|
|Specific||Eastern Channel and southern North Sea|
|Track charts||(0.14 MB)|