Annual summary of visits to the Breton control stations since 1994

Since the early 1990s, follow-ups have provided information on migration flows in order to assess the status of migratory fish populations and monitor their evolution. They are carried out at control stations that allow continuous counting of fish passages. They are located at strategic points such as thresholds equipped with a crossing device (fish passage) or a trapping system. These stations target all migratory species or specifically certain species such as eel. Each control station is characterised by structural biases linked to the configuration of the site. Under certain hydrological conditions (flow, tide), the maximum efficiency of crossing devices — thus control stations — cannot be ensured. A number of fish can escape counting by crossing the obstacle without passing through fish passes or traps. Depending on the monitoring stations, the migration balance therefore takes into account the exhaust. 3 levels of qualification of the data have been determined: — A number of staff which corresponds to a minimum number of — A corrected number of staff: correction of expert counting (based on non-functioning time of video counting and threshold franchisability time, function of flow) — An estimated number of staff: specific study to assess the escape of a migratory species at a control station The geographical layer " stacomi_bzh " presents the annual summary of the counts for each control station. This layer is vector point type in shapefile format in Lambert 93. It includes an award table showing the numbers counted by species and per year for each control station. __Origine__ The benchmark chosen is the Scan25 __ Partner Organisations__ Brittany Great Migrators, FishPass, FDAAPPMA22, FDAAPPMA22 and FishPass for EDF, SCEA for FDAAPPMA 29, FDAAPPMA 29, Brittany Region, INRAE UE3/FDAAPPMA56, Morbihan Water, EPTB Vilaine, FDAAPPMA 35 [See this sheet on geo.data.gouv.fr](https://geo.data.gouv.fr/fr/datasets/805c52467e5a614fa96492cfe3f6a91161d3e637)