FN Archimer Export Format
PT Rapport
TI International Bottom Trawl Survey (IBTS2021-Q1) - French cruise report.
OT International Bottom Trawl Survey (IBTS2021-Q1) - Rapport de la campagne française
BT 
AF LAZARD, Coline
   VERIN, Yves
   AUBER, Arnaud
AS 1:1;2:1;3:1;
FF 1:PDG-RBE-HMMN-LRHBL;2:PDG-RBE-HMMN-LRHBL;3:PDG-RBE-HMMN-LRHBL;
C2 IFREMER, FRANCE
SI BOULOGNE
SE PDG-RBE-HMMN-LRHBL
UR https://archimer.ifremer.fr/doc/00691/80333/83418.pdf
LA English
DT Report
CR IBTS 2021
   INTERNATIONAL BOTTOM TRAWL SURVEY (IBTS)
BO Thalassa
DE ;North sea;GOV;beam trawl;MIK;abundance;stock assessment
AB In 2021, the French NS-IBTS Q1 survey was conducted as part of the International Bottom Trawl Survey program carried out by main countries bordering the North Sea in order to assess abundance and stocks distribution, independently of commercial fisheries data. The first target of the NS-IBTS Q1 survey is to provide a diagnosis on the main commercial fish species by estimating their abundance per age. A standardized protocol is rigorously applied by all participants. The R/V Thalassa sampled the eastern part of the Channel and southern North Sea (until 56° N) from 19th January to 9th February 2021. During daily time, 56 hauls, lasting 30 minutes, have been carried out with a GOV bottom trawl. A total of 82 fish species have been collected, determined and measured, and 2605 otoliths (for age estimation) have been collected for 13 species. This year, whiting (Merlangius merlangus) represented 30% of the total biomass caught followed by herring (Clupea harengus, 26%). During the night, 107 MIK net have been deployed to calculate an index for herring and sprat larvae abundance. Within each station, a CTD sensor was deployed to record environmental parameters (e.g., temperature, salinity and oxygen) all along the water column, from surface to bottom. In order to study the whole marine ecosystem, some additional studies were carried out in the context of the Marine Strategy Framework Strategy and for various research projects. 
PY 2021
PD APR
DI 10.13155/80333
ID 80333
ER

EF