Thalassa IBTS2017

Cruise plan

Cruise Info. 
Ship name (ship code)Thalassa (35HT)
Cruise identifierIBTS2017
Cruise period2017-01-19 — 2017-02-10
Port of departureBoulogne, France
Port of returnBoulogne, France
ObjectivesThe knowledge of the state of fish stocks is necessary to define management measures. Analysis carried out during the IBTS (International Bottom Trawl Survey) cruise are essential to elaborate the propositions by the ICES working groups (International Council for the Exploration of the Sea). Then, these propositions are examined by the European Union which defines management of fish stocks.

Thus, a real-time diagnosis on the targeted populations is obtain througt IBTS surveys. For that, working methods were defined by all countries involved in this programme: for example, the use of a standard bottom trawl and the sampling of all the areas by two different research ships. In order to determine indices of herring and sprat larvae (0 groups), each participating vessel operates with a MIK net during the night (Methot Isaac Kidd).

For 20 years, the southern part of the North sea has been allocated to the French Research Vessel and since 2007, the Eastern Channel has been integrated the whole sampled area. As interactions and migrations of stock between these two areas are important, Eastern Channel is often associated the North Sea for stock assessment. Herring for example which is exploited all the year in the North sea comes into the Channel during November and December for reproduction. More precise information on larvae indices are obtain when this area is sampled.

In addition to the works done for the IBTS program, other works are implemented onboard Research Vessel Thalassa
- an acoustic prospection in the English Channel,
- a study on fish spwaning areas, using the Continuous Underwater Fish Eggs Sampler device (CUFES),
- a species-specific winter abundance and distribution of the winter planctonic community (phyto and zoo plancton),
- a monitoring study on the structure and distribution of the benthic macro invertebrates communities.

Chief scientistYves Verin (IFREMER Channel and North Sea Centre)
ProjectICES International Bottom Trawl Survey (IBTS)
Coordinating bodyInternational Council for the Exploration of the Sea (ICES)
NPRCThalassa IBTS2017 NPRC thalassa_ibts2017.pdf (0.49 MB) 
Ocean/sea areas 
GeneralEnglish Channel
North Sea
SpecificEastern Channel and southern North Sea