Simple download service (Atom) of the dataset: River Linens colonised by the European Angle (ANG)

The new management plan for migratory fish in the Seine-Normandie Basin for the period 2016-2021 was adopted by the Basin Coordinating Prefect on 21 June 2016.Developed by the Management Committee for Migratory Fishes, it issues, in consultation with the main water users, guidelines and recommendations to enable the management of habitats and human activities compatible with the protection of migratory fish. The development and monitoring of the plan is possible, in particular through the Migratory Association SEINORMIGR, which drives the migratory component throughout the basin and follows the indicators of the PLAGEPOMI.A general and rapid scarcity of the eel is observed throughout its range. This situation led in 2003 to the development of a Community action plan for the management of European eels. An eel management plan for France was thus created, including a local part of the Seine-Normandie basin. It is considered that the eel can colonise the entire basin. Eel harvests make it possible to determine an index of abundance and size structures of the eels sampled, as well as their distribution over the longitudinal profile of the watercourse, with the aim of first establishing a state of the European eel population on the Seine-Normandie basin. Abundance indices are particularly effective on potentially migrant eels smaller than 300 mm (civelles, 1 summer yellow eels, non-sexually differentiated yellow eels). They then provide information on the stock of growing immature eels, and identify the species’ active colonisation front in each study basin. Fluctuations in downstream abundance are the result of unequipped offshore structures (estuarine nozzles, dams at the bottom of the estuary) or structures whose management is not adapted to the behaviour of the species in the run (floor gates). These first and upstream barriers cause breakdowns of abundances, affect the colonisation rates of the youngest migratory individuals, as well as the distribution of the species, especially females upstream of streams.This layer reflects the linear stream colonised by the European Angle as of 2014:• “Linear colonised by migrant individuals (active colonisation front”: linear colonised by eelspotentially migrants of less than 300 mm;