At one time the river was noted for its substantial
brown trout population, with the length from
Pontrilas to
Skenfrith producing record catches. Numbers fell substantially during the 20th century and especially after the 1960s but in more recent years the trout fishing has improved dramatically and the Monnow catchment once again ranks as one of the best wild trout fisheries in England and Wales and it is now also noted for the
grayling fishing. A recently opened fish pass at Monmouth allowing migratory fish to by-pass a previously impassable weir has once more given
Atlantic salmon and
sea trout access to the majority of the catchment and salmon were seen jumping at the now dismantled Kentchurch weir for the first time for many years in the Autumn of 2008. The Monnow Rivers Association works to improve fishing habitats on the river and to encourage responsible fishing. ==Hydroelectric power==