Category Archives: RIVERS AND WATERWAYS

PIONEERING NEW APPROACHES TO EXMOOR’S INVASIVE SPECIES PROBLEM

Castration and electrocution are two ground-breaking new ways of tackling invasive plant and animal species being trialled in Exmoor National Park, highlighted as part of Invasive Species Week recently.

Japanese and Himalayan Knotweed are two of Britain’s most invasive weeds and they have caused extensive damage to several of Exmoor’s most precious watercourses, such as the Lyn, Heddon and Barle – all Sites of Special Scientific Interest (SSSIs).

A ten-year collaboration between Exmoor National Park Authority, the Environment Agency, Natural England and the National Trust to try to control the problem has proved highly successful, with the plant now being managed across an area the size of six Wembley football pitches, thanks to the support from local landowners.

Exmoor is now among a handful of UK sites where a pioneering new method of control is being trialled, involving electrocuting the weed’s root system. It is hoped the new approach will avoid the need for repeat spraying with herbicides, which can impact the environment, although not nearly so much as the plants themselves.

Elsewhere on Exmoor’s waterways, another non-native invasive species is being dealt a tough blow. An estimated quarter of a million North American signal crayfish inhabit the River Barle, with potentially devastating consequences for our native wildlife.

The River Barle Crayfish Project is now tackling the problem in an innovative new way never before tried outside of captivity – by castrating the larger, more dominant male signal crayfish. After this harmless procedure, they are returned to the river where it is hoped they will continue to outcompete smaller males to control breeding.

Later this year findings are due to be published on the project – which exists as a partnership between Exmoor National Park Authority, the Environment Agency and the River Exe & Tributaries Association.

Ali Hawkins, Wildlife Conservation Officer at Exmoor National Park Authority, said: “It’s great to be trialling innovative new techniques like these that could potentially help with the problem of invasive species on Exmoor, without further damage to our delicate ecosystems.

“Many of the habitats here are protected for their uniqueness and scientific value, so it’s vital that we do all we can to safeguard them from these foreign invaders. We’d love more volunteers to come forward and help us stop the spread by signing up to one of our training days, or reporting sightings of invasive species through our website.”

People wishing to volunteer for these two projects and others like them can find out more at www.exmoor-nationalpark.gov.uk/get-involved.

WESTCOUNTRY RIVERS TRUST SUGGESTS SIX WAYS TO HELP YOUR LOCAL RIVER THIS YEAR

Environmental charity the Westcountry Rivers Trust is urging local people to do their bit to look after the region’s rivers this year.

Nick Paling, Head of Evidence and Engagement at the Westcountry Rivers Trust (pictured), says: “Rivers are crucial to our health, happiness and prosperity. It is now well known that being in nature is good for our health and wellbeing.  Spending time by the river can be extremely relaxing and rejuvenating and a great antidote to modern life. Most of the time we take them for granted, but at the Westcountry Rivers Trust we would like to encourage more people to do their bit to look after their local river.

“Once you have discovered your local river, we hope you will be inspired to do more to protect it. From volunteering for a river clean-up, to taking part in monitoring activity, there is lots you can do to help the Westcountry Rivers Trust in our efforts to restore and protect the South West’s rivers.”

The Westcountry Rivers Trust has identified six ways people can help to protect their local river.

1. Get out and enjoy your local river
Many of our rivers are hidden underground, but the South West has a number of beautiful riverside walks. The Westcountry Rivers Trust website can help you to find your local river wrt.org.uk/your-river . Once you know where it is, try to visit it every now and again. If more of us get to know our local rivers we can also all do our bit to keep an eye on them and report any problems, such as littering or pollution.

2. Go for grass in your garden
More pressure on parking spaces means that many front gardens have now been paved or concreted over. Hard surfaces cannot soak up water, so this water flows across the surface into the drainage system, which can become overwhelmed and cause flooding. In many of our towns and cities, there is just not enough space for surface water to drain away. Localised flooding is becoming a real problem.

The Westcountry Rivers Trust is encouraging people to choose grass for their gardens. Nick Paling says: “If you really want to keep your paving or concrete, think about including at least some permeable surfaces – perhaps incorporate a planted border, place a water butt under your guttering or choose gravel for your driveway.”

3. Keep your drains clear
The water companies have a major job to keep our water clean and safe to drink. British households apparently pour enough fat down their drains every year to fill seven Olympic swimming pools. The Westcountry Rivers Trust recommends using empty jars or margarine tubs to collect it, then throw it away. Other common culprits for blocked sinks are coffee grinds, produce stickers and broken eggshell, which should instead be binned or composted to prevent unwanted waste entering our water systems.

4. Don’t waste water
Reducing your water usage won’t just save you money, it will also help the environment. From having a water butt in your garden, to taking shorter showers, there is so much that you can do. South West Water also provides free-water saving devices, which you can get here www.savewatersavemoney.co.uk/free-water-saving-packs.

5. Get your septic tank checked
If septic tanks are not emptied regularly or are not working properly, they can overflow and discharge straight into the river. This is a particular problem during heavy rain. So, if you have a septic tank – and plenty of rural homes in the South West do – then make sure you understand how to keep it working properly and stop it overflowing. This Government document consult.defra.gov.uk/water/reform-regulatory-system-small-sewage-discharges/results/your-sewage-your-environment-leaflet-july-2015.pdf outlines what you need to do.

6. Become a citizen scientist
The Westcountry Rivers Trust now has more than 100 volunteer ‘citizen scientists’ who are helping to monitor the health of rivers across the South West. Find out how you can join them here wrt.org.uk/get-involved/.

HELP BRIDGE THE GAP AT WOODSIDE

A fundraising campaign has been launched by Exmoor National Park’s CareMoor for Exmoor* to replace a much-loved feature of Exmoor – Woodside Bridge, which has provided a crossing of the East Lyn river near Lynmouth for over a hundred years.

Woodside Bridge had to be removed last December following an inspection which revealed that the softwood timber beams had come to the end of their life. The bridge was replaced in the 1950s after the Lynmouth Flood and again in 1993 by the Royal Engineers working with Exmoor National Park. At 17.3m/57feet, the structure is the longest single span countryside bridge in the National Park.

Thousands of people used the bridge each year to enjoy the short, easy circuit  taking in Middleham Memorial Gardens along with the beauty and wildlife of the river and woodland valley. The bridge is an important link for visitors and the local businesses which they support.

Dan Barnett, Access & Recreation Manager at Exmoor National Park, said: Many people are surprised to learn that the bridge is not recorded as a public right of way which means there is no duty for local authorities to replace it, so we need your help.

“We are keen to replace the bridge as soon as funds allow so we are asking visitors, residents and anyone who cares about Exmoor to make a donation. Any amount, large or small, will help and we hope to reach our target by Christmas which will allow us to get the bridge installed ready for Easter next year when the main visitor season begins.

“We now have a price of £65,000 to install a high-quality new structure. This is a steel beam supported bridge with hardwood timber work which will have a very long design life.”

The land where the bridge is sited is owned by The National Trust, which is a partner in this project.

For more information and to contribute to the Woodside fund please visit: www.exmoor-nationalpark.gov.uk/caremoor/woodside www.exmoor-nationalpark.gov.uk/caremoor/woodside

* CareMoor for Exmoor is the Authority donation scheme for Exmoor National Park. It offers everyone who has been inspired by Exmoor an opportunity to contribute to the upkeep of the environment of the National Park and its future. Donations help fund Nature, Heritage and Access projects to keep Exmoor special. For more information  visit: www.exmoor-nationalpark.gov.uk/caremoor
 

PHOTO AT TOP: Colour-tinted image shows two ladies walking on the footpath opposite Tors Road, early 1900s. Photograph kindly donated by Paul Sheppard.

SOUTH WEST SALMON GET NEW SPAWNING GROUNDS

The Westcountry Rivers Trust is creating new salmon spawning habitats by adding gravel to rivers in Devon and West Somerset. Funded by South West Water, as part of the National Environment Programme, the project aims to increase the number of salmon and trout by creating gravel beds, which these fish need to build nests for their eggs.

Hundreds of tonnes of granite gravel have now been added to sections of the River Avon and River Teign on Dartmoor and the Haddeo on Exmoor in Somerset. Along with researchers from Plymouth University, the Westcountry Rivers Trust will monitor the movement of the gravel along the river as well as comparing the numbers of salmon and trout with previous years.

Many rivers have lost their natural gravel beds because of obstructions, such as dams or weirs. These barriers prevent rocks and stones from travelling down the river, which has led to a shortage of spawning sites for salmon and trout. The team has now added 400 tonnes of gravel to a 2.5mile section of the River Avon, near Shipley Bridge. Similarly, gravels have been added to over half a mile of the River Teign, below the South Teign as well as to a stretch of the Haddeo on Exmoor.

The team was on a tight deadline to get the new gravel into the river in plenty of time for the spawning season. Adult salmon lay their spawn in freshwater gravel beds, known as ‘redds’, in the autumn and the eggs hatch in the winter.

Matt Healey, Land and Fisheries Officer for the Westcountry Rivers Trust, said: “Gravel beds are essential for salmon and trout to spawn. They seek out these habitats to cut redds because when water travels through the gravel it carries oxygen to the eggs, which they need to survive.  If there isn’t enough gravel, then there is limited spawning opportunity, and if there is too much silt in the gravels the eggs become smothered and don’t survive. These gaps between the stones also help create environments for invertebrates, providing food for the fish.

“We introduced some new gravel to these sites last summer and are already seeing how it is settling into the river bed, creating natural habitats in the river. By carrying out the work on a bigger scale this year, we are hopeful that we will see an increase in fish numbers in the coming years.”

By adding stones of different sizes, the Westcountry Rivers Trust aims to make the new habitats as natural as possible. Plymouth University researchers are electronically tagging some of the stones, so they can monitor how the gravel moves over time. This research will help scientists understand how far the stones move, and where they settle, to assess how successful the project has been in creating spawning habitats.

David Gilvear, Professor of River Science at the University of Plymouth, said: “The effect of dams on reducing fish spawning habitats due to them trapping gravel has long been known, but there have been few examples of trying to address this. This project is therefore to be applauded. It is important as well to learn from the project, in order to maximise the success of future gravel augmentation projects. We feel privileged to be providing the scientific expertise to be able to monitor the movement of the introduced gravels and the creation of gravel habitats for fish. The findings of our work will be of interest not only locally but nationally and internationally.”

Dr David Smith, Environment Manager at South West Water, said: “We all rely on dams to ensure we always have sufficient supplies of safe tap water to drink but we are always mindful of the impact the could have on a river’s natural ecology. We are happy to support this project which we hope will increase numbers of fish and invertebrates in these rivers.”

PHOTO: MATT HEALEY AT SHIPLEY BRIDGE