A SALMON was filmed playing hide and seek at  the Diglis Fish Pass window in Worcester. 

In the video shared by Unlock the Severn, the camera-shy salmon can be seen darting its tail in and out behind the wall of the Diglis Fish Pass window.

Salmon are just one of the many species of fish that have been recorded at the window, with over regular appearances including twait shad and sea lampreys. 

Two cameras are always stationed in the viewing room, which monitors every fish which passes through.

The viewing window is illuminated with a backlight so that the cameras can detect fish at all times of the day.

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What is a Fish Pass?

Malvern Gazette: 11 pools at the Diglis Fish Pass where fish travel up stream.11 pools at the Diglis Fish Pass where fish travel up stream.

The purpose of a fish pass is to allow fish to move past manmade blockages in water. In Diglis, the weir means that many fish looking to travel upstream struggle due to the two-metre separation.

The weir was installed in the 1840s to create a deeper, more reliable pool of water upstream for boats.

Stronger fish like salmon are occasionally able to get past the weir by jumping, but many species do not possess the required strength.

The pass consists of 11 small pools, each just 20 cm higher than the last, making it more manageable for the fish to swim through.

The fish detect the stream of water in the river and can travel upwards, with walls in each pool relieving some of the force created by the water. 

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Unlocking the Severn, the team behind the Diglis Fish Pass is running a series of events this August at the fish pass, including family sessions, documentary screenings and general visits.

There will be 25-minute bookable visits in August, which take you through the fish pass from the terrace to the underwater viewing gallery.

The tour will give opportunities to learn about scientific monitoring and have the chance of spotting wild fish.

There will also be family-friendly viewing sessions, where three families at a time can observe the viewing window.

To book trips, visit https://www.unlockingthesevern.co.uk/august-events-at-diglis-fish-pass/.