Rehabilitation efforts for Atlantic salmon in the Meuse basin area: Synthesis 1983-1998

In the 1950s, Atlantic salmon had become extinct in the river Meuse basin, mainly owing to the construction of navigation weirs. In 1987 started a reh abilitation program of Atlantic salmon in Belgium. Stockings are being perf ormed in six tributaries of the river Meuse, using eyed eggs, parr and pre- smolts obtained from foreign eggs reared in a hatchery of the 'Service de l a Peche'. By the end of 1998, 896033 young salmon have been released in the wild, especially in the river Ourthe basin. In most of the cases, the eval uation of stocking operations indicates good adaptation of parr in the trib utaries where they are stocked, with autumnal 0+ parr densities up to 20-30 ind 100 m(-2). However, fish mortality may occur when smolts pass through the turbines of the hydropower stations in the river Meuse (5% per power pl ant), and most of the fish passes located downstream of Namur are not suita ble for anadromous fish migration. The paper reports the results of stockin g experiments, the evaluation of mortality rates in turbines and the advanc ement of programmes aiming at the restoration of downstream and upstream mi gration (construction of fish migration facilities).