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24, chemin de Borde Rouge –Auzeville – CS52627
31326 Castanet Tolosan CEDEX - France

Dernière mise à jour : Mai 2018

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Total Authorised Catch (TAC)

To make sure that the salmon population replacement rate is sufficient, salmon fishing is managed by establishing and enforcing a Total Authorised Catch (TAC) for each river catchment,.

A TAC is defined as the number of salmon that can be caught without endangering the population. The TAC system has been in operation on the rivers of Brittany and Lower Normandy since 1996 and in Upper Normandy and the Artois-Picardie water authority area more recently.

How TAC works

Salmon populations are made up of two types of fish:

  • Spring salmon. These are salmon that have spent several winters at sea and are liable to be caught in our rivers between March and June;
  • Grilse. These are salmon that have spent only one winter at sea and are liable to be caught in our rivers between June and October.

During the fishing season, a simple rule is applied to distinguish between grilse and spring salmon: any catch equal to or larger than the size set by COGEPOMI (Comité de Gestion des Poissons Migrateurs) is regarded as a spring salmon. For the Armorican massif catchments, that size is 67 cm). At the end of the year, the formal distinction between spring salmon and grilse is based on interpretation of each individual's life history from examination of sampled scales.

To adjust the TAC to management requirements for each catchment: 

  • specific "spring salmon" TAC is set, in terms of numbers of fish. If the TAC for spring salmon is reached, the catchment's fishery can be closed temporarily, until it is reopened for grilse.
  • An overall TAC is the overall number of salmon that can be harvested from the catchment. If this TAC is reached, the fishery can be closed for the rest of the season. It is calculated according to the types and morphological characteristics of the salmon caught.