SACROIS is a data crossing algorithm that produces professional fishing activity data series (validated, consolidated and qualified production and effort data) for the vessels registered in the Community Fishing Fleet (CFP) file. SACROIS selects the best of the available information sources to produce the reference fishing activity data. SACROIS consists of an operational application for reconciliation, verification and consistency checks of different unitary data streams. The SACROIS algorithm does not correct the data, its objective is to : - provide the best possible estimate of the various elements making up a tide from the available data sources - to identify the incompleteness of the various data sources and to propose a synthesis completed by indicators of data qualification resulting from the crossings. Twice a month, the SACROIS algorithm produces a new data source, a synthesis of all the available data sources: the reconstructed SACROIS tides. The SACROIS data have been calculated since 2000 for all fleets for which data are available: - North Sea - Channel - Atlantic (excluding tropical seiners), - Mediterranean (excluding bluefin seiners), - DOM (Reunion, Mayotte, French Guiana and the West Indies).

The NourDem project aims to carry out annual trawling cruises in the three estuaries of the Seine, the Loire and the Gironde.

The aim of these cruises, which took place on the Thalia, was to evaluate the abundance of the scallop stock in the Charentais channels.

Since 2001, an annual stock assessment of Manila (Ruditapes philippinarum) and European (Ruditapes decussatus) clams has been carried out in March in the Gulf of Morbihan and the Noyalo River. The objectives of this survey are : 1) estimate by direct assessment, the biomass of the stock and its geographical distribution; 2) estimate the exploitable biomass and exploitation potential for the sampled sites in particular, in areas reserved for professional fishing; 3) to establish a diagnosis, with a medium-term vision, on the state of the stock; 4) to propose the implementation of appropriate management measures. Two cruises were also carried out in 1996 and 1997.

The 62 RESSGASC campaigns allow the quarterly assessment of the quantities of various species (hake, sole, Norway lobster, etc.) discarded by fishing vessels (individuals below legal landing size). This information, together with data collected from the demographic structure of landings (using samples from auctions), is essential for the evolution of commercial fish stocks.

As part of the implementation of the monitoring programme of the Marine Strategy Framework Directive (MSFD), the monitoring of demersal fish and cephalopods in coastal soft environments was deemed a priority. Annual observation campaigns of coastal nurseries on soft bottoms were carried out by the Laboratoire Halieutique Méditerranée of the Ifremer station in Sète. The objectives of these campaigns are 1. To evaluate the density, biomass and distribution of fish and cephalopods by trawling, in particular benthic and demersal juveniles (red mullet, gurnard). To do this, around one hundred standardised trawl surveys were carried out over the entire coastal strip of the Gulf of Lion situated between 5m and 40m depth. 2. To systematically measure the size of the individuals collected in order to characterise the importance of the nursery function in the areas observed and to better understand the population dynamics of local species. 3. To gain a better understanding of the coastal zone ecosystem by systematically identifying all the species encountered (including benthic and pelagic invertebrates other than fish and cephalopods), the macro-waste observed and by characterising their hydrological habitats (CTD, oxygen, fluorescence, pH, turbidity, etc.).

The objective of this cruise, which has been taking place in the English Channel - Baie de somme since 1980, over 5 days in September, is to evaluate the natural multi-year fluctuations of the stands and to analyze the possible impact of the nuclear power plant on the marine environment and resources. It makes it possible to determine annual indices of abundance and distribution of flatfish and other species (shrimp, pout, whiting).

Within the framework of the establishment of a nuclear power plant on the coast of the town of Flamanville, Electricité de France has entrusted Ifremer with ecological and fishery studies on the site's surroundings. One of the expert assessments consists of conducting two shellfish fishing campaigns each year. Their objectives are to monitor the natural fluctuations of the main indicators selected during the start-up of the plant and to evaluate the impact of the plant on the surrounding fishery.

The COMOR cruises, which took place on the Thalia, aim to assess the abundance of the scallop stock (and if necessary to determine the presence of toxic algae) in the Seine Bay.

The Bargip project : acquisition of scientific data and knowledge to produce advices on integrated management of European sea bass (Dicentrarchus labrax) in North-East Atlantic.