Shock treatment rescues salmon: Nigel Burnham sees migrating fish being stunned and then helped on the way to their North Yorkshire spawning grounds

THREE men in a boat with hand nets and a glass fibre pole capable of dispensing a 240-volt electric shock looked like they could have been doing a spot of illegal fishing on the river Esk in North Yorkshire yesterday.

In fact they were working for the National Rivers Authority, lifting salmon and sea trout manually over a delapidated Victorian weir at Sleights so that the fish could continue their migration to the spawning grounds in the Esk's shallow headwaters.

The helping hand was being offered on Yorkshire's only significant salmon river because the NRA is currently repairing the weir's fish 'pass' - a series of tanks 12 to 18 inches high up which the salmon and sea trout can leap. The walls of the pass have started to collapse, making its ascent almost impossible.

'The weir was built in 1891 and the fish pass has needed repairing for the last 20 years,' the NRA's area fisheries officer, Chris Firth, said.

'It had deteriorated so badly that many fish could not reach the top of the weir and so were effectively trapped in a pool downstream, sitting ducks for poachers.'

The work, which will cost pounds 80,000 and take another four weeks to complete, involves 'damming off' the pass with copper so that it can be drained and rebuilt.

While the work is in progress fish approaching the weir are stunned by an electric shock and then moved by hand nets into dustbins filled with water. NRA scientists then measure and weigh the fish, and take scale samples to age them, before releasing them upstream of the weir.

Mr Firth said: 'We're using a generator to power an electrode at the end of a glass fibre pole. When a fish comes within a certain distance it is temporarily stunned so we can lift it out. We've moved 700 like this - some as heavy as 15lb - in two weeks.

'It has been a unique opportunity to acquire some invaluable scientific data about the lives and movements of salmon and sea trout.'

Mr Firth believes the work will help restore the Esk to one of Britain's finest salmon rivers: 'It will help a lot more of them to reach their spawning grounds on the moors.'

(Photograph omitted)

Suggested Topics
Start your day with The Independent, sign up for daily news emails
Have you tried new the Independent Digital Edition apps?
ebooks
ebooksAn introduction to the ground rules of British democracy
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
SPONSORED FEATURES
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Account Manager - Media Sales - £36,000 OTE

£28000 - £36000 per annum: Recruitment Genius: This award-winning company, whi...

Recruitment Genius: C# .NET Developer / Application Support - Junior

£21000 - £25000 per annum: Recruitment Genius: This business has an industry r...

Recruitment Genius: Office Administrator

Negotiable: Recruitment Genius: They make daily deliveries to most foodservice...

Recruitment Genius: Transport Planner

Negotiable: Recruitment Genius: They make daily deliveries to most foodservice...

Day In a Page

Turkey's conflict with Kurdish guerrillas in Iraq can benefit Isis in Syria

Turkey's conflict with Kurdish guerrillas in Iraq can benefit Isis in Syria

Turkish President Erdogan could benefit politically from the targeting of the PKK, says Patrick Cockburn
Yvette Cooper: Our choice is years of Tory rule under Jeremy Corbyn or a return to a Labour government

Our choice is years of Tory rule under Corbyn or a return to a Labour government

Yvette Cooper urged Labour members to 'get serious' about the next general election rather than become 'a protest movement'
Singapore's domestic workers routinely exploited and often abused in the service of rich nationals

Singapore's hidden secret of domestic worker abuse

David Cameron was shown the country's shiniest veneer on his tour. What he didn't see was the army of foreign women who are routinely exploited and often abused in the service of rich nationals
Showdown by Shirley Jackson: A previously unpublished short story from the queen of American Gothic

Showdown, by Shirley Jackson

A previously unpublished short story from the queen of American Gothic
10 best DSLRs

Be sharp! 10 best DSLRs

Up your photography game with a versatile, powerful machine
Solved after 200 years: the mysterious deaths of 3,000 soldiers from Napoleon's army

Solved after 200 years

The mysterious deaths of 3,000 soldiers from Napoleon's army
Every regional power has betrayed the Kurds so Turkish bombing is no surprise

Robert Fisk on the Turkey conflict

Every regional power has betrayed the Kurds so Turkish bombing is no surprise
Investigation into wreck of unidentified submarine found off the coast of Sweden

Sunken sub

Investigation underway into wreck of an unidentified submarine found off the coast of Sweden
Instagram and Facebook have 'totally changed' the way people buy clothes

Age of the selfie

Instagram and Facebook have 'totally changed' the way people buy clothes
Not so square: How BBC's Bloomsbury saga is sexing up the period drama

Not so square

How Virginia Woolf saga is sexing up the BBC period drama
Rio Olympics 2016: The seven teenagers still carrying a torch for our Games hopes

Still carrying the torch

The seven teenagers given our Olympic hopes
The West likes to think that 'civilisation' will defeat Isis, but history suggests otherwise

The West likes to think that 'civilisation' will defeat Isis...

...but history suggests otherwise
The bald truth: How one author's thinning hair made him a Wayne Rooney sympathiser

The bald truth

How thinning hair made me a Wayne Rooney sympathiser
Froome wins second Tour de France after triumphant ride into Paris with Team Sky

Tour de France 2015

Froome rides into Paris to win historic second Tour
Fifteen years ago, Concorde crashed, and a dream died. Today, the desire to travel faster than the speed of sound is growing once again

A new beginning for supersonic flight?

Concorde's successors are in the works 15 years on from the Paris crash