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This project is a collaboration between the University of º¬Ð߲ݴ«Ã½, the ,  and the .

Atlantic salmon Salmo salar are a migratory fish species that travel from the sea to spawn on gravel beds in rivers. Salmon were once abundant in the rivers of Yorkshire, including the river Don, which passes through the centre of º¬Ð߲ݴ«Ã½. In the past, shoals of salmon would have been seen jumping through º¬Ð߲ݴ«Ã½'s rivers as they travelled upstream to their spawning grounds.

Many of º¬Ð߲ݴ«Ã½'s place names are linked to salmon, such as Salmon Pastures and Loxley ('Lox' being an old word for salmon). Up until the 18th century º¬Ð߲ݴ«Ã½ had a lucrative and thriving salmon industry. However, the weirs that had been built to power the mills and navigate the rivers, blocked the salmon's migration routes, causing the extinction of salmon from the Don by 1796 (C. Firth pers. comm.).

Pollution resulting from the industrial revolution turned the river Don into a dead river, devoid of life. 

Heavy pollution of the rivers began during the industrial revolution and continued until the 1970s. Many factories are still located on the banks of the river Don due to their historic need for water power, or the use of the river as a dump for byproducts and waste.

These included paint manufacturers, the steel industry and even armaments factories during wartime. Legislation safeguarding water quality was passed in the 1970s and was the first step in the attempt to clean up our rivers and allow life to return.

Many agencies have worked hard to remove weirs and create fish passes so that migratory fish, including salmon and eels, can return to their historical spawning grounds. The agencies involved include the , the , ,  and  among others.

In 2019, two salmon were spotted in the river Don near º¬Ð߲ݴ«Ã½ (). These were the first salmon to return to º¬Ð߲ݴ«Ã½ in 220 years and a cause for celebration. These records indicate that river connectivity has improved and pollution levels have fallen.

We are using new environmental DNA (eDNA) techniques to detect the presence of salmon in Yorkshire's rivers. We will monitor their return and map the extent of their reach upstream. This will help to identify barriers to their migration routes in order to focus efforts at these sites to remove these obstructions. Water samples have been taken at various locations along the river Don and Dearne and will be tested for the presence of salmon DNA. 

Salmon images kindly supplied by .

Personnel

University of º¬Ð߲ݴ«Ã½
Dr Deborah Dawson, Project Leader (d.a.dawson@sheffield.ac.uk)
, Erasmus internee (2019), now at the University of Hull
, Research Technician

Don Catchment Rivers Trust
, Director
, Trustee & Director
, Community Engagement Officer

Environment Agency
, Fisheries Technical Specialist
, Don Catchment Fisheries Officer

Yorkshire Water
, Principal Ecologist
Dr Rachel Naden, Invasive Non-Native Species and Biosecurity Advisor

Background reading

• Firth C (1997)  900 years of the Don fishery. Environment Agency Report.
• .  Environment Agency. 18 January 2019.
• . Yorkshire Water. 7 June 2017.
• . Canal & River Trust. 3 June 2016.
• . Environment Agency. 21 May 2016.
• . Environment Agency. 17 December 2015.
• .  Environment Agency. 15 June 2015.
• . Environment Agency. 23 May 2014.
• . BBC º¬Ð߲ݴ«Ã½ & South Yorkshire. 28 January 2011.
•  BBC News 29 August 2006.

Funding

This DNA study has been funded by an EU Erasmus internship (2019), Yorkshire Water, UK and Research England.