A program for the " Development of fishing activities on Lac de Serre-Ponçon ", initiated by SMADESEP in October 2007, now has a provisional budget of €142,000.00.Among the development avenues envisaged, one focuses on the creation of semi-natural spawning grounds for phytophilous fish such as pike: this involves a budget item of €23,000.00.
Preserving the environment for pike spawning A challenge on Lac de Serre-Ponçon
Pike, an emblematic species, requires a submerged plant substrate to lay its eggs. However, the necessary vegetation is limited on Lac de Serre-Ponçon due to the significant variations in water level resulting from hydroelectric activity.
Industrial constraints and ecological challenges
The tidal range resulting from hydroelectric activity creates extreme conditions, such as winter frosts, prolonged summer flooding and significant sediment deposits. These constraints make it difficult for many plant species to adapt. Despite these challenges, pike play a crucial role in regulating whitefish populations, helping to maintain the lake's ecological balance.
Collaboration for preservation The SMADESEP project
Under the impetus of its President, Victor BERENGUEL, SMADESEP has initiated a collaboration with the Hautes-Alpes Fishing Federation. The aim of this partnership is to find solutions to encourage the reproduction of phytophilous species, in particular pike, by means of revegetation actions.
Experimentation at two strategic sites
Two sites have been selected for experimental tests: the Riou Bourdoux creek (Savines le Lac commune) and the Hyvans beach (Chorges commune). These sites have characteristics conducive to the spawning of phytophilous species.
Greening projects An overview of work in progress
Riou Bourdoux site
Last week, Charles Queyras TP completed 80 linear meters of earthworks at elevation 776m NGF. In April 2012, the second phase will begin with the installation of an anti-swamping geotextile and a "geotube" cordon. These elements will encourage the development of vegetation over an 850m² area. After implementation, a manual selection of suitable plants (sedges and phragmites) will be planted before the water rises to its maximum level (780m NGF).
Chorges site
The planned development consists of installing a riprap 12m wide and up to 1.50m high to level a spawning terrace of around 120m². The use of a watertight geomembrane will maintain a favourable level of humidity on this terrace, through which run-off water flows. The creation of pioneer vegetation on this terrace is intended to create an ideal spawning area for phytophilous species such as pike.