A RARE species will be among many to benefit from new improvements to the fish pass at Boroughbridge on the River Ure in North Yorkshire.

The Environment Agency and British Waterways have just put the finishing touches to a £76,000 joint scheme to improve fish passage over Boroughbridge Weir which will help lampreys, an internationally protected species, to migrate and breed.

Lampreys are one of only two surviving remnants of the most primitive invertebrates the Agnatha or ‘jawless fish’. Today, only three species of this eel-like creature remain in Britain and their habitats are protected by an EC directive.

Many fish migrate up rivers each year to their spawning grounds to breed. These places can be at the top of river systems and in the past have been made inaccessible to the fish because of physical barriers such as weirs.

The original fish pass on the River Ure was built in the 1800s and was designed to help salmon and sea trout in their migration upstream. Although the weir allowed these fish to pass, it was in need of some upgrading to accommodate all types of fish.

In addition to salmon and sea trout, coarse fish such as barbel, dace and chub migrate and lamprey also need to migrate upstream to find the best spawning grounds. Better and more in-depth knowledge of the conditions all fish need to migrate has helped the specialists come up with the new modern fish pass.

Fisheries scientists from the Environment Agency and engineers from British Waterways worked together to carefully calculate, design and build the improvements to the weir. These include a new chamber on the bottom of the pass to ease access to it, new weir boards and modifications to the existing structure to give the most preferable flow conditions for most fish species.

David Morley, Environment Agency Fisheries Officer said: “This is a fantastic scheme and we are very grateful to British Waterways, who own the weir and fish pass, for their commitment and enthusiasm.

“We are confident that the new fish pass will make conditions better for all migratory fish, not just salmon and sea trout and hope that this will bring benefits to the lamprey and fish populations in the Ure and Ouse river system.

“This is a step towards improving access to the upper reaches of the River Ure for all migratory fish and we will continue to work with our partners, especially British Waterways, to make as many improvements as possible in the future.”