The BBC recently reported on the improvements to salmon populations around the UK, due to conservation efforts. Within the report, they featured footage of salmon jumping at a weir, on the River Dove. While it is always exciting to see this, it really highlights why fish passes are needed.
Fish jumping at the weir and unsuccessfully failing to move upstream waste large amounts of energy in the process. This impairs both their ability to continue their journey upstream and their chance of spawning successfully, as summarised very well by Tim Birch from the Derbyshire Wildlife Trust in the BBC footage. The construction of a carefully designed fish pass can therefore have a highly significant impact on populations of salmon, but also other species such as trout (which you can also see jumping at the weir in the BBC footage).
Being able to contribute to the improvement in populations of species such as salmon is hugely rewarding and it is great to see recoveries such as this being covered by the media.