Durham Hydro – latest update!

17 Feb

A meeting between the Wear Anglers Association, the Environment Agency and Durham County Council  was held at the end of 2018 in a further attempt to resolve the problem of migratory fish entering the Archimedes Screw chamber.

The main points to emerge from this meeting were:

• The strobe lighting hasn’t worked! It has now been turned off and will be removed shortly.

• Durham County Council still don’t want to install fine mesh screens at the base of the chamber because of the difficulty in maintaining the screens and the loss of water head. With finer screens the water velocity increases and the head reduces. They are of the opinion that this head loss is unacceptable and the turbine will automatically shut down. Calculations were produced to support this theory.

• The Environment Agency produced an interesting photograph of the scheme on the River Ettrick at Selkirk where there are no issues with migrating fish. However, the photograph shows the fish pass on the outside (river side) of the screw chamber outlet and not the inside (bankside) as at Durham.

• Durham County Council now intend introducing a scheme to stop fish jumping into the screw chamber that consists of 250 mm wide overlapping flaps of heavy duty plastic. This is very similar to the plastic flap doors used on warehouses and walk in freezers. There will be a stack of flaps of different lengths so that as the water rises the longest ones will lift up but leave the shorter ones behind hanging vertically down wards. A similar scheme  is in use on an Archimedes Screw on the Yorkshire Esk but for sound reduction not to prevent fish jumping into the screw chamber.

• The Environment Agency are planning to replace the central and lowest “pool and traverse” fish pass opposite the screw by a small Larnier fish pass. It is hoped that this new pass will be installed in the summer of 2019. This may help draw fish away from the screw as they migrate up the south side of the river and then swim across the face of the lower weir. In addition the fish passage at the Fulling Mill weir is also being looked at.

  • There is considerable disappointment and frustration in angling circles that this issue is taking so long to resolve. If the new ‘flap system’ does not work then legal action may follow!

Kielder Hatchery.

12 Jan
Atlantic salmon are under threat but a North East hatchery which is celebrating its 40th anniversary has helped bring them back to the River Tyne.
Richard Bond releases young sea trout
Richard Bond releases young sea trout (Image: unknown)

Salmon were once so plentiful in the Tyne it is said that apprentices had clauses inserted in their indentures restricting the number of times employers could serve up the fish for dinner. And in Berwick, servants had a similar stipulation restraining their masters from dishing up.

But by the 1950s, salmon had vanished from the by then grossly-polluted Tyne.

Today, the salmon are back, largely through major improvements in water quality, while the Kielder hatchery in Northumberland has also played a significant part in restoring fish stocks.

Salmon eggs hatching at Kielder
Salmon eggs hatching at Kielder (Image: unknown)

The recovery of the Tyne and its current status as the best river in England and Wales for salmon rod catches is a bright spot in a picture of concerns over a marked decline in the abundance of Atlantic salmon across the species’ geographical range over the last 15-20 years.

To highlight the situation and the importance of the species, 2019 has been declared International Year of the Salmon. The Kielder salmon hatchery, run by the Environment Agency, will be holding events. But this year will be a special one for the hatchery for other reasons. It is the 40th anniversary of the first salmon bred by the hatchery being released into the Tyne.

Richard Bond releases young salmon and sea trout
Richard Bond releases young salmon and sea trout (Image: unknown)

It will also be the first full year for the £100,000 refurbished visitor centre at the hatchery, which tells the story of the salmon’s life cycle and also features a tank which replicates the underwater world of the North Tyne, containing salmon, bullhead, stone loach, minnow, dace and lamprey. It is also the year when the first hatchery-raised juvenile freshwater pearl mussels, in danger of extinction in the North Tyne, will be released into the wild.

The hatchery was set up to produce 160,000 juvenile salmon a year for stocking the Tyne to compensate for the loss of the Kielder Burn spawning grounds, which were cut off from the river by the building of the Kielder reservoir.

Richard Bond releases young sea trout
Richard Bond releases young sea trout (Image: unknown)

For seven years the hatchery also stocked an additional 200,000 salmon to mitigate for the river disruption from the building of the second Tyne Tunnel and incidents of mortality of adult fish returning to spawn from incidents of low oxygen levels in the estuary.

Last year the hatchery stocked 360,000 salmon and 20,000 sea trout in the Tyne and its tributaries. That included 4,000 sea trout offspring introduced into the Ouseburn for the first time, and also the River Team.

This year the stocking target for the Tyne catchment is 300,000 salmon and 20,000 sea trout.

Around 40,000 juvenile salmon will go into the Kielder Burn. When the fish grow to be smolts – ready to migrate to sea usually after two years – they are captured in a trap and carried around the reservoir to be released into the Tyne at Falstone.

Tagged fish have shown that the 107km journey down the river to the sea can take up to 36 days – and as little as four.

Salmon eggs hatching at Kielder
Salmon eggs hatching at Kielder (Image: unknown)

Estuary mortality for returning adults can be caused by a combination of factors such as hot, dry summers and neap – or small – tides which means lack of freshwater flow, leading to low oxygen levels. The last bad year was 2003 when around 1,000 fish died.

During the hot weather last summer, Kielder reservoir played a vital role in reducing the risk of fish deaths in the upper estuary. Additional releases of water from the reservoir made by Northumbrian Water at the Environment Agency’s request between June 22 and August 10 amounted to 35 billion litres.

Phil Rippon the fisheries technical specialist for the Environment Agency in the North East, said: “We continuously monitor the oxygen levels in the estuary during conditions such as we saw in the summer and do what we can to help migrating fish reach their spawning grounds.

The hatchery's Jess Anson releasing salmon and sea trout into the River Tyne tributaries
The hatchery’s Jess Anson releasing salmon and sea trout into the River Tyne tributaries (Image: unknown)

“This includes additional releases of water from Kielder reservoir to increase freshwater flows when oxygen levels in the estuary become critical. Previous research from similar summer conditions has shown that releases from Kielder sometimes triggers upstream movement of salmon and sea trout, helping them during hot and dry conditions.

“These additional releases have undoubtedly saved many salmon in 2018.”

Over the last eight years, an annual average of 30,000 salmon have returned naturally to the Tyne.

The hatchery has stabilised this improvement, as has the removal of obstacles to help fish reach their spawning grounds. It begins its breeding programme in November by capturing 55 pairs of returning adults. Eggs are fertilised at the hatchery and the young fish are gown on and set free in the summer.

Kielder salmon centre staff Jess Anson (left) and Richard Bond (right) with Environment Agency North East area director Oliver Harmar (centre)
Kielder salmon centre staff Jess Anson (left) and Richard Bond (right) with Environment Agency North East area director Oliver Harmar (centre) (Image: Newcastle Chronicle)

Schools are given 100 eggs each so that pupils can watch the hatching and growing process, ending in them releasing their fish.

A female salmon lays between 6,000-7,000 eggs and it is estimated that around two will survive to go on and become spawning fish.

“At the visitor centre, people can learn about the life cycle of the salmon and their incredible journey from the Tyne to Greenland and back,” said hatchery manager Richard Bond. The visitor centre is open from April-September.

The hatchery’s bid to save the North Tyne’s freshwater mussel began in 2003. A total breeding stock of 81 mussels are now in an artificial stream outside the hatchery.

The mussels begin to breed at 15 to 20 years old and can live to be more than 100. But no mussels younger than 40 to 50 years old have been found in the North Tyne.

“If nothing was done in 15 to 20 years the population would become so small that it would not survive,” said Richard.

The female mussel produces two to four million barely visible juveniles which float in the water and seek to attach themselves to the gills of trout. Months later they drop off and settle on the bed of the river.

This year 768 two-year-old mussels raised by the hatchery will be released into the wild.

“We are absolutely delighted to have managed to raise the first North Tyne mussels bred in captivity, with the aim of preventing the population from becoming extinct,” said Richard.

Catch and Release on North East Rivers!

11 Jan

The Environment Agency has released a guidance note as to how the new Salmon byelaws affect northeast rivers with regard to catch and release viz;

The agency has set a target of voluntary catch and release rates in excess of 90% starting from 2019 on rivers assessed to be ‘Probably at Risk’ – ie Tees and Coquet in the North East.

This will be reviewed in 2020 with a view to either continuing the voluntary measures or implementing mandatory catch and release byelaws if the stocks cannot be protected by voluntary means. The decision will be made on a river-by-river basis, determined by local considerations.

For rivers Probably not at Risk – ie Tyne and Wear, the EA hope to achieve high levels of C&R at or approaching 90%, and will work with anglers, the Angling Trust and others to understand how this can be achieved.  If these levels of C&R are not achieved,  the EA will not seek to introduce mandatory C&R unless the performance of the salmon population fell to Probably at Risk, and voluntary measures were proving ineffective in achieving the 90% level.

So whilst the Wear and Tyne remain ‘Probably not at Risk’ (and hopefully subsequently improve to Not at Risk) the EA will maintain voluntary C&R arrangements regardless of actual levels of C&R.

These targets apply only to Salmon and not Sea trout.

The only northeast and Yorkshire rivers to have mandatory catch and release are the Rivers Aln, Blyth, Wansbeck, Tyne Derwent and Warren Burn. and all of the Yorkshire Ouse system including the River Ure.