Traversing the Esk

Christopher Watt – River Esk Project Officer

Hi there, I’m Chris and I’ve just recently joined the National Park Authority as a River Esk Project Officer, having moved down from Scotland, and seemingly brought the weather with me! My role will involve working with farmers and landowners to implement river restoration techniques that seek to improve the water quality of the River Esk catchment.

Over the last month I have started to piece together the Esk catchment, worked with volunteers in delivering practical tasks and began undertaking fish obstacle river surveys. It has certainly been a varied introduction to the role and area.

Autumn colours in Westeredale. Copyright NYMNPA.

Volunteers braved the drizzly elements back in October to repair a broken fence on the River Esk, near Castleton. Thankfully, the task allowed us to remain on dry land and avoid venturing into the river which was rather swollen after recent heavy rainfall. A bankside tree had fallen and crushed a section of the fence-line, slackening the wire and dislodging posts. The volunteers assisted with installing new posts, including a heavy duty straining post, re-attaching the wires and finally tightening them. The volunteers worked extremely hard and it was a pleasure to meet and work with them. The task was also completed in one afternoon and the sun even came out, which is a bonus!

This task was one of the many on-going works to restore and enhance the riparian habitats of the River Esk. Maintaining riverside fences assists in keeping cattle and sheep away from the bankside vegetation and so causing sediment loading through erosion. Bankside vegetation stabilises the soil and is an important habitat in its own right. The reduction of sediment loading should help improve conditions for conservation priority species such as Atlantic salmon (Salmo salar), Sea trout (Salmo trutta) and Freshwater pearl mussel (Margaritifera margaritifera) which favour clean, fast-flowing rivers and streams.

In combination to riparian habitat enhancements, we have also been undertaking fish obstacle surveys stretching from Westerdale down  to Goathland. These involve inspecting an assortment of obstructions from weirs, fords and culverts and assessing how severe they impinge on fish migration. At each obstacle the length, width and height are recorded, along with a written assessment of the level of severity the obstacle poses to migrating fish populations.  

Esk Catchment weir after high rainfall event. Copyright NYMNPA.

Due to recent high rainfall, many of these obstacles have been partially or fully submerged, and although looking dramatic, have been just too dangerous to take measurements from. Electro-fishing will also accompany these surveys at a later date to inform us about fish species diversity and abundance at each obstacle. The purpose of these surveys is to update our records on obstructions across the catchment and prioritise where mitigation measures would best be targeted to benefit fish populations of the Esk. Migratory fish are a vital aspect of the biodiversity of the river.

Esk Catchment culvert and ford system. Copyright NYMNPA.

Electrifying activities

Victoria Franklin – Conservation Trainee

Last week some National Park Volunteers (all fully trained) have finally been able to carry out the first electro fishing surveys this year along the River Esk. Delays had been caused by the weather.

The priority are sites up and downstream of the Sewage Treatment Works (STW) and one Combined Sewer Overflow (CSO) in the upper catchment. The first day of surveying was at Commondale.

The concept of electro fishing is to collect samples of fish living within the river, the higher the fish count the healthier the river should be. This will also show the type of fish living in our rivers, the cleanliness of the river and theoretically what the invertebrate population is like along that stretch of river.

The river levels had settled down by Thursday meaning the water was back to a slow flow and all the previous rain had made the water clear giving the perfect conditions for electro fishing.

We fished the river in two 50m sections, one upstream and one downstream of water treatment works. This was done using a zig zag motion to ensure that no area was left unfished. Each 50m section was fished three times to ensure a fair population of fish were caught.

Esk electro fishing October 2019. Copyright NYMNPA.

The equipment used to stun the fish is called an electro fisher and consists of a positive charge the anode at the front and a negative charge called the cathode which trails along the back. These are both attached to a battery which is worn by the person conducting the fishing, today it was Volunteer Paul. Both the anode and the cathode must be in the water to cause an electro charge which is what stuns the fish, but don’t worry rubber thigh waders were worn by everyone so the electro pulse did not affect us humans like it did the fish. The rest of us were in charge of catching the stunned fish in nets alongside the anode, which is harder than it looks as the fish soon spring back to life! They are then transferred into a bucket from the nets.

Esk electro fishing October 2019. Copyright NYMNPA.

We set the voltage output at 150- 200 volts which is enough to temporarily stun the fish making them easier to catch in the net. Once the section of river has been fished the data collection begins. The fish are identified – on this day we found 57 trout downstream and 104 upstream with the largest being 180mm and the smallest recorded at 52mm. The information collected will now be analysed before being sent onto Yorkshire Water, they will then compare this with the other locations which are due to be fished over the next few weeks, and that will all help inform management of their sites as necessary.

An amazing day was had by all the volunteers and staff that attended. More data collection will happen in the next few weeks on different sites along the Esk.

Esk electro fishing October 2019 - small trout. Copyright NYMNPA.

Cumulative enhancements: Part One

Briony Fox – Director of Conservation

Over the last two years, a number of projects have been delivered to enhance the landscape and ecology of the North York Moors National Park.

These projects have been delivered under four key themes – Access, Environment, Cultural Heritage and Tranquility; all related to the special qualities of the National Park.

Here’s a few examples…

Upgrades to Rights of Way such as at Boggle Hole where improvements have been made to the bridleway to the beach by removing steps.

Boggle Hole - before. Copyright NYMNPA.

Boggle Hole - after. Copyright NYMNPA.

 

 

 

 

 

 

 

 

Riverbank in poor condition. Copyright NYMNPA.

The restoration of river bank habitat on the river Esk by fencing (to prevent trampling by grazing animals) and planting trees which will in turn stabilise the banks and prevent sediment entering the river, so enhancing water quality which is essential for endangered species such as Freshwater Pearl Mussel.

Tree planting and fencing works to stabilise the bankside. Copyright NYMNPA.

Drystone wall, Coxwold - before repair. Copyright NYMNPA.

 

Restoration of historic landscape features such as our iconic dry stone walls

 

Drystone wall, Coxwold - after repair. Copyright NYMNPA.

Commissioning of a Dark Skies Audit to understand where the darkest skies in the park are and to inform policy and a new management plan related to protecting the dark sky asset.

2019 light pollution map of the NYM area with survey points (yellow / green dots) shown.

Areas with the most light pollution are shown in yellow / orange while darker areas are grey. This work will help us to prioritise our efforts to keep our darker areas dark and reduce pollution in our brightest areas.

This is just a snapshot of what we’re doing to enhance the National Park area through this project and this work will continue long into the future. Other work includes ongoing woodland creation to offset carbon emissions and promoting the fabulous activities and opportunities that the North York Moors offers for visitors.

This is only the start.

Big Thank You’s

Kate Bailey – Catchment Partnership Officer

The BIFFA funded project ‘Restoring Freshwater Mussel Rivers in England’ came to an end in 2018. We were involved because of the River Esk in the north of the National Park. The £300,000 made available helped towards safeguarding Yorkshire’s last remaining population of Freshwater pearl mussels (Margaritifera margaritifera).Image of the River Esk, August 2013. Copyright Sam Jones, NYMNPA.

A huge amount of work was achieved in the Upper Esk catchment during the three year period of this project, working closely with the farming community to address diffuse pollution from agriculture. Pollution including sedimentation detrimentally affects water quality and therefore impacts on aquatic species like the mussels.

For most of its three years the project was led by Simon Hirst, our River Esk Project Officer. Simon worked with 38 land managers in the Upper Esk catchment delivering improvement works to help keep pollution including sedimentation out of the river and its tributaries. This has meant:

  • Over 8km of riparian fencing installed
    This helps stabilise the river banks and creates buffer strips to reduce the amount of runoff from fields getting into watercourses, as well as providing rough habitat along the river corridor for insects which are so important for fish, birds and small mammals.
  • 650 trees planted along the river banks of the Esk and its tributaries
    The majority of which were planted by our dedicated River Esk Volunteer Group.
    Trees help stabilise the banks and so. like with the fencing, reduce sedimentation.
  • 34 alternative watering points installed
    This is to reduce poaching in fields and along the river banks, and to keep stock and their effluent out of a watercourse.
  • Approximately 5.5km of riverbank re-vegetated with woodrush planting
    Another 130m of river bank was stabilised using hazel/willow whips. Re-vegetation helps stabilises the river banks
  • Over 500m of guttering and downpipe installed on farm buildings
    To capture clean water before it gets onto the ground, picks up nutrients and sediment, and then runs into a watercourse.
  • 1,237 m3 of concreting in farm yards.
    The new surface is profiled to collect dirty water before it can enter a nearby watercourse.

Big Thank You to Biffa for supporting the Restoring Freshwater Mussel Rivers in England project.

Big Thank You to all the local land managers who worked alongside Simon on the Esk, contributing a lot  of their own time and capital to complete these improvement works.

Big Thank You to our dedicated Mussel Volunteers who have played such a vital role in this delivery project, and all the other volunteers that helped out like the Explorer Club and the 1st Marston Moor Scout Group.

River Esk Volunteers, taking a well earned rest. Copyright NYMNPA.

And one more Big Thank You to Simon Hirst. Last year the North York Moors National Park had to say goodbye to Simon because he moved on to a new role working on the River Holme in Huddersfield. His enthusiasm and knowledge will be greatly missed by us and the Esk’s Freshwater pearl mussels.

Born to be Wild

Dr Ceri Gibson – Pearl Mussel Projects Manager, Freshwater Biological AssociationFBA logo

The Freshwater Biological Association has been working with the North York Moors National Park for the last 3 years on the ‘Restoring Freshwater Mussel Rivers in England’ project (funded through Biffa Award). Our role has been to rear juvenile mussels ready for reintroduction back into the River Esk at some appropriate time in the future when the habitat is restored and the water quality improved enough to support them.

Rearing juvenile freshwater pearl mussels (FPM) is a 24 hrs a day, 365 days of the year operation with our staff attending the hatchery even on Christmas Day to ensure that the mussels, and the host fish that they rely on as part of their lifecycle, are all okay.

Proof that the FPM are looked after even on Christmas Day. Copyright FBA.

But it’s not a bad job over here on the shores of Windermere. Whilst the wind may funnel up the lake at times, come rain, snow or sunshine, the views are wonderful and we have a great team.

View looking north over Lake Windermere. Copyright FBA.

The adult mussels are kept in circular tanks in our hatchery connected to tanks which contain host fish. Keeping fish and mussels in close proximity under controlled conditions improves the chances of the mussels successfully completing their lifecycle. We try to maintain the mussels in as natural an environment as possible so they are kept outside in flowing water provided from Windermere.

We constantly monitor the mussels and fish to record when glochidia (freshwater pearl mussel larvae) are released from the females and when these glochidia have grown sufficiently on the fish gills. Then we set nets to collect juveniles as they drop off their fish hosts and transfer them to trays in our juvenile rearing facility. Whilst other techniques of bank-side encystment and seeded gravel reintroductions have been used for some rivers we believe that rearing juveniles beyond their most vulnerable pedal feeding stage, when they live amongst the gravels before filtering free-flowing water, will yield better reintroduction survival rates and allows us the opportunity to learn more about these fascinating creatures.

Back in 2016, we worked with Simon Hirst (River Esk Project Officer) to translocate more adult mussels from the Esk to the hatchery. This exercise followed a recently commissioned brief from Natural England and was very carefully monitored. It proved successful and we have been collecting the captive bred juveniles in large numbers over the last two seasons. FPM larvae are carried on the gills of specific fish hosts for up to 10 months as part of lifecycle. It is interesting that in recent years the Esk glochidia grow to excystment size (350-400 microns long) and drop of the fish hosts within 2 to 3 months at the hatchery. We are therefore monitoring their survival in the rearing trays carefully.

We have been working with other river populations to prepare juveniles for reintroduction into their native rivers. The trays they are reared in are indoors where the juveniles are well protected. So we have set up flume systems to expose captive-bred juvenile mussels to diurnal and seasonal conditions which better reflect the river situation they will be reintroduced to. Once in the flume we can control flow to ‘teach’ them how to adapt to flood and drought conditions. During these experiments we record how many mussels are deeply buried, how many remain on their side on the surface of the gravels and how many are roaming about using their muscular foot. We also record whether they are siphoning water or not.

We look forward to the time that we can repeat these experiments for the Esk population but in the meantime have a look at some of our other, older juveniles filmed in their flume – click here. Or organise a group visit and come and see us at the Ark to visit the Esk juveniles and learn more about what we do.

Rainbow from Mitchell Wyke. Copyright FBA.

Biffa Award logoBiffa Award is a multi-million pound fund that helps to build communities and transform lives through awarding grants to community and environmental projects across the UK, as part of the Landfill Communities Fund. 

 

Call of Nature

This might not be the nicest subject to ever feature on this Blog – but it’s important stuff.

Kate Bailey – Catchment Partnership Officer

The National Park Authority is a partner in the Esk and Coastal Streams Catchment Partnership. All partners have an interest in improving water quality in the catchment.

The Catchment Partnership is therefore very happy to be involved in the Call of Nature Yorkshire campaign which aims to reduce inadvertent pollution getting into rivers and the sea when off-mains sewage systems aren’t maintained as they need to be. In rural areas, like the Esk and Coastal Streams catchment, individual homes/farms and small settlements are often not connected to the mains sewage network and so waste – from toilets, sinks, showers, baths, washing machines, dishwashers – is contained in cesspits, or treated in septic tanks or package sewage treatment plants, on site.

  • Cesspits are very basic, these tanks hold waste without any treatment. They need to be emptied regularly and the waste removed.
  • Septic tanks hold waste water where it settles and separates with sludge at the bottom and liquid at the top. Bacteria breaks down the organic matter in the tank. The effluent at the top drains onto a soak away area so that other bacteria in the soil can break down the remaining pollutants. The effluent cannot be discharged directly into a watercourse (which include ditches, field drains, small streams, rivers, lakes etc)
  • Package treatment works are a bit more technical than septic tanks. An electric pump brings in air which helps bacteria breaks down organic matter more effectively. This means under certain conditions that effluent can be discharged into a watercourse.

The Call of Nature Yorkshire campaign is raising awareness of the potential problems if these off-mains systems aren’t maintained properly and providing guidance on maintenance.

Local surveys by the Environment Agency have shown elevated levels of phosphates in certain areas of the catchment, and this could be partly due to individual sewage treatment systems and the domestic detergents and human sewage they’re supposed to treat. This isn’t the only issue; diffuse pollution from agriculture e.g. fertiliser, manure and slurry can also cause elevated nutrient levels in watercourses.  Phosphate acts as a nutrient and can trigger excessive plant growth in rivers and streams. This depletes the oxygen in the water, smothers the river bed and blocks out the sunlight damaging these important ecosystems. The Glaisdale Beck Restoration Project and the Biffa funded Esk Project is working with farmers to tackle agricultural impacts. But that leaves the accidental domestic waste.

General binding rules were introduced in 2015 and apply to people who are not connected to the mains sewage network.  All tanks need to be maintained to prevent leakage and to be emptied regularly to prevent over flow, any faults should be fixed immediately and maximum discharge volumes should not be exceeded (without a specific permit). If waste water that hasn’t been adequately treated gets out, it can end up polluting watercourses and beaches so damaging everyone’s environment and the nutrients and sewage released can harm both humans and wildlife. It’s much easier to maintain a off-mains system correctly than replace it when it fails. A poorly maintained system can also have a detrimental effect on the value of the property and so affect a house sale. Dark smelly liquid, sewage fungus (a slimy grey growth), a backing up toilet and a poorly-draining soak away are all indications that there is something wrong.

How to reduce domestic phosphates getting into local watercourses wherever you are (some of these suggestions are applicable if you do or don’t have an off-mains sewage treatment system):

  • Make sure you know how your own system works and where it is located
  • Make sure tanks are emptied regularly (by a licensed company) to ensure the lower layer of sludge doesn’t build up
  • Check all parts of your system regularly – make sure any faults with the system are fixed immediately
  • Make sure your system can manage the amount of waste being produced by the household – old tanks were not designed to manage the volumes used now e.g. washing machines, dishwashers. You might need to invest in a new system.
  • Don’t connect rainwater drainage pipes or guttering into an off-mains system
  • If possible space out your use of a washing machine and a dishwasher so the waste water/detergent isn’t entering the system at the same time.
  • Use ‘environmentally friendly’ products – only use small amounts.
  • Only use minimum amounts of bleach or disinfectant – these chemicals kill bacteria that is actually vial to breaking down waste
  • Don’t flush solid items down the toilet which can block the system and lead to overflow.
  • Don’t pour grease/cooking oil down the sink. Don’t pour paints or solvents or down the drains.

If you do have one of these off-mains sewage treatment systems and would like further information please can call the Environment Agency on 03708 506 506.  The Call of Nature Yorkshire website also has lots of useful fact sheets with further information.

Call of Nature Yorkshire logo

Environment Agency logo

Electric expeditions

People's Postcode Lottery logoUPDATE

The Yorkshire Esk Rivers Trust have recently been awarded a grant from the Postcode Local Trust, a grant giving charity funded entirely by players of the People’s Postcode Lottery. This grant means we can purchase our own electric fishing equipment and train more volunteers to undertake surveys in 2018. If you’re interested in getting involved with surveys – please contact Kate

.

Kate Bailey – Catchment Partnership Officer

Electric fishing is a method used to determine fish populations in watercourses, commonly carried out by organisations such as the Environment Agency and the various River Trusts. Sites across the River Esk catchment up in the north of the North York Moors have been monitored using this technique over the past 20+ years as a way of estimating juvenile fish populations. In the last five years an increased number of sites have been surveyed along the Esk and we’ve managed to gain a better understanding of fish population changes.

This summer we took the chance to learn the technique ourselves. Simon Hirst our River Esk Project Officer, six keen volunteers and I went on a fully certified electric fishing course. Our new specialist team is made up of local anglers and existing River Esk Volunteers, all of whom care about the river and want to safeguard the species that live in it.

The two day course was essential to ensure our ‘in house’ monitoring can be carried out safely and to make sure the information we collect is scientifically robust so we can draw conclusions from it.

Methodology

During an electric fishing survey an electrical current is sent through the water which temporarily stuns the fish enabling them to be easily caught in nets. To produce an electrical current one team member wears the backpack which holds a battery and control box. A cathode trails behind the backpack resting in the water and the operator holds a pole with a metal ring on the end (anode). Once the operator places the anode in the water and turns the system on, the electrical circuit is complete and a small current passes through the water. The equipment has multiple safety features to ensure surveys can be carried out safely for all involved – that’s the fish, the operator and all the other team members in the water and on the bankside.

Two or three team members follow behind the operator with the nets and buckets ready to quickly remove the stunned fish from the river.

September 2017 - Electric Fishing in Esk. Copyright NYMNPA.

Once caught, the stunned fish are transferred into a large holding tank on the bankside. Each fish is measured using a special measuring board – this helps us estimate the relative age of the fish. The size and species is noted down and the fish is then released back into the river as quickly as possible.

September 2017 - Electric Fishing in Esk. Copyright NYMNPA.

Sites are identified – usually an approximately 50 metre stretch of river – and the team enters the water at the downstream end and walks upstream fishing as they go until they reach the top of the site. It is useful to fish up to a feature in the river, for example a natural barrier like a riffle, to ensure the greatest percentage of fish can be caught. If the end of the site was situated in the middle of a pool, for example, the fish would be driven beyond the far end and hence not be recorded.

Once the site has been fished, it also needs to be measured – this allows us to work out species density (i.e. the number of fish per unit area). We measure the channel width at 10 metre intervals and calculate an average width. This average width is multiplied by the length of river surveyed to give us a total area of river fished! Fish densities are usually recorded as the number of fish per 100 metres2

September 2017 - Electric Fishing in Esk. Copyright NYMNPA.

Health & Safety

Fish welfare (and the welfare of our volunteers and us) is extremely important, there is little point in measuring fish populations to help sustain numbers if we end up with dead fish. When electric fishing is carried out correctly this methodology does not harm the fish. As part of the training we learnt how to set the control box to the correct settings to ensure the electrical current will temporarily stun the fish but will not cause any damage. This is determined by the electrical conductivity of the water – a reading is taken before carrying out the surveys.  It is important to temporarily keep the fish in a large holding tank in the shade to ensure there is sufficient oxygen for them and that the water temperature does not increase too much, and we release the fish back to the river as soon as possible.

Fish aside, all team members who are in the river must ensure they are fully insulated (e.g. rubber chest waders) and must not put their hands into the water when the backpack is switched on. Prior to undertaking a survey each stretch of watercourse is checked for hazards and a site risk assessment produced. This is to make sure there are no ‘nasty’ surprises (such as deep holes!) when the team enter the water.

Why

Electric fishing is a really good way of estimating fish populations and this is extremely important on the River Esk. Atlantic salmon is a species that is struggling due to a wide variety of issues including water quality and habitat issues, barriers to fish migration and poor survival rates at sea. Monitoring juvenile numbers across the Esk every year will help to highlight areas where these issues are magnified and can therefore help target the conservation work we’re undertaking in the catchment to improve water quality and riparian habitats.

Our electric fishing team were out and about in the catchment in the autumn surveying six specific sites. It proved a success – the surveyed fish were released back and all the volunteers survived. Species recorded included Brown trout (Salmo trutta), Atlantic salmon (Salmo salar), Stone loach (Barbatula barbatula), European eel (Anguilla Anguilla), Bullhead (Cottus gobio) and Brook lamprey (Lampetra planeri). Overall our results showed healthy fish populations at each site, although as expected relatively low numbers of Atlantic salmon were found.

We plan to monitor juvenile fish populations annually in September, to build up our understanding of the local status of the Atlantic salmon and the other species found in the Esk.

Conservation recruits

Abi Duffy – Conservation Trainee and Sam Newton – Natural Heritage Trainee

Abi Duffy, Conservation Trainee. Copyright NYMNPA.I’m Abi Duffy, and I have recently started as a Conservation Trainee. I graduated from the University of Liverpool with a degree in Geography in July 2016 and since then I have been working towards gaining employment within the conservation sector. I am really interested in developing my knowledge and experience in this two year position with the National Park.

Sam Newton, Natural Heritage Trainee. Copyright NYMNPA.My name is Samuel Newton and I have started in the position of Natural Heritage Trainee with the National Lottery funded This Exploited Land of Iron Landscape Partnership Scheme. I have always been interested in the environment, leading to my graduation from Newcastle University with a degree in Ecology earlier this year. I am keen to use this opportunity to gain as much experience as possible of working in conservation.

Our first two months have been both varied and interesting as we’ve been contributing to a wide range of projects. We’ve taken advantage of the end of summer to be out in the field most days surveying.

Water vole surveying

One particularly memorable day was water vole survey training, for which we headed up to Fylingdales. This surveying entails walking a stretch of stream looking for signs of Water vole (Arvicola amphibious). The most obvious signs are droppings, which are ‘tic tac’ shaped and tend to be green, and are used for territory marking. Where droppings are flattened and more have been deposited on top this creates a ‘latrine’. We also looked for piles of nibbled grass, with a 45° cut angle at the end – characteristic of voles, as well as for burrows and footprints.

The training links in with our Water vole project which is aiming to secure the few remaining populations of Water vole within the North York Moors. The animals have North York Moors Water Vole. Copyright Elspeth Ingleby, NYMNPA.suffered from habitat loss and also the spread of invasive American mink. I (Sam) have been mapping water vole and mink survey results, mostly collected by our dedicated group of Water vole survey volunteers. These records create a base from which management of habitats and also mink can be carried out.

Botanical Surveying

We have been visiting species rich grasslands across the North York Moors, with a range of different underlying ecological conditions. By surveying the plant species and their abundance on these sites we can try and ensure management fits the individuality of each one, and that certain species are not being lost or becoming dominant to the detriment of others. Our Linking Landscapes volunteers also survey grassland within the National Park each summer; many volunteers survey the same site each year which helps identify changes. The volunteers send in their results to us for analysis.

Some of the interesting and beautiful flowers we have seen so far include Eyebright (Euphrasia officinalis), Common Spotted Orchid (Dactylorhiza fuchsia), Harebell (Campanula rotundifolia) and Fairy Flax (Linum catharticum). We also joined in with the Conservation Volunteers cutting some of these grassland sites where they’re not grazed and importantly raking off the cuttings to stop the grasslands becoming too nutrient rich. Nan Sykes’ book ‘Wild Flowers of North East Yorkshire’ has proved invaluable in helping improve our botanical ID skills.

Harebell. Copyright Sam Newton, NYMNPA.

MoorFest

As part of National Parks Week back in August, I (Abi) got involved with a MoorFest event at our Sutton Bank National Park Centre letting people know about the species rich grassland resource within the North York Moors. We had many families chatting to us about wildflowers and asking us questions about the grassland. This was a good way to help communicate to the wider public the work that farmers and the National Park do together to conserve and enhance grassland sites.

Moonwort at Sutton Bank. Copyright Ami Walker, NYMNPA.The triangular meadow out of the front of the Sutton Bank National Park Centre is a great example of such grassland. Back in June, before beginning in our roles, we both took part in a Volunteer training day there; we found the rare fern Moonwort and several Common Spotted Orchids among a vast array of species. This site is a good quality species rich grassland in top condition, and with continuing management we hope to keep it that way.

Triangle Meadow, Sutton Bank - Common spotted orchid at the forefront. Copyright Ami Walker, NYMNPA.

West Arnecliff Woodland Survey

In early August we were given the opportunity to follow up on research work done by the previous Research Student at the National Park, Sam Witham. Sam had been investigating the impact of deer browsing in woodland by constructing small exclusion enclosures, in order to establish whether these allowed greater natural regeneration. This is part of the National Park’s long term PAWS restoration project. Non-native conifers had already been removed from this site at West Arnecliff and the continuing research is to help understand how best to assist the regeneration of the Ancient Woodland features and habitat.

Japanese knotweed surveying

Something else we have been involved with is the River Esk project – in particular surveying stretches of the river for Japanese knotweed (Fallopia japonica). This destructive invasive has the potential to spread rapidly along the river banks generating sedimentation and damaging the river environment. There has been control work over the last decade but it’s important to keep on top of the plant and where it is coming back it needs to be treated as soon as possible to prevent a new outbreak. So the surveying is important and has become a bit of a right of passage for new members of the Conservation Department.

Conclusion

So far we have really enjoyed the first two months in our new roles We are looking forward to going out into the field even more and meeting and working with the land owners and land managers who shape the landscape of the North York Moors.

It is great to have the opportunity to understand and contribute to the work the National Park is doing, while learning about working in conservation at the same time.

Abi, Sam and Bernadline surveying in Rosedale. Copyright Elspeth Ingleby, NYMNPA.

Letter from Scotland

Sam Jones – previous River Esk Project Student

I still recall the morning as, fresh-faced and hopeful, I sat in the back of a bus trundling along country roads towards the North York Moors. As we turned a corner and crested a ridge I was gifted my first view of the National Park and I could feel butterflies in my stomach, this would be my first real job in conservation. This was the start of my life serving the environment as I saw it then (and still do now I suppose). That was about four years ago, things have moved on quite a bit since then.

I worked for the National Park Authority on a year in industry placement back in my third year of University assisting with the Esk Pearl Mussel Salmon Recovery Project lead by Simon Hirst aimed at conserving the remaining Freshwater pearl mussel population in the River Esk. It was a wonderful and varied experience.

At the end of my time I spent a week wading through ocherous becks in the very upper reaches of the Murk Esk. I was rather cheekily using my last few weeks working at the National Park to collect data for my upcoming final year project. I collected samples of upland invertebrates from becks through moorland and coniferous woodland to test the effects of acidification on aquatic life, and to see how the impacts of acidic moorland and plantation woodlands compare. My project has now been published although you need journal access to see the whole thing. Simon has asked me for a basic summary of my findings and conclusions – so here goes…

I used aquatic invertebrates as indicators of environmental degradation. It’s well recognised that moorlands and uplands can have acidification issues, and the North York Moors may well be one of the most extreme areas for it in the UK with its nearby zones of industry. Acid issues have been recorded in local becks in the past, including severe fish kills. However my results were a little surprising. Originally I thought that plantation woodland, being the newer and least natural habitat (compared to moorland which is also man-made habitat), and having less ability to slow down and buffer the incoming water, would have a much more degraded community. However, my results showed significantly more acid sensitive species living in the woodlands than the moorland. This was despite the fact that previous studies had recorded lower pH values (i.e. more acidic) in plantations than in moorlands. I think that the reason for this is the woodlands provide a more diverse and richer freshwater environment for the invertebrates to live in. This is a good sign as it shows that the conifer plantation woodland, that so much of our countryside is dominated by, may not have such a bad effect on aquatic life as once assumed. The aquatic communities were also generally healthier than would have been expected given the severe acidification. I think this shows that the species of invertebrates living in the uplands of the North York Moors are well adapted for highly acid conditions and that, despite the seemingly poor chemical results, life in the upland becks is thriving.

What happened next? After I graduated from the University of York I went on to work for Natural England, the Environment Agency and now I’m part of an ecological consultancy. I’ve come full circle, and recently I was lucky enough to get accepted for a PhD up in Inverness studying Freshwater pearl mussels. Apparently they needed someone with more waders and bucket experience than lab experience, and I fitted the bill.

Scotland is one the great bastions of the Freshwater pearl mussels with populations of tens of thousands in numerous rivers and multiple populations with favourable age structures and reproductive ability (unlike in the Esk sadly). As such, my PhD is to study these populations and monitor them using traditional methods. However the focus of the investigation is to allow comparison of conventional survey methods with new eDNA techniques. Environmental DNA (eDNA) is a method of monitoring species or habitats using the DNA that is freely found in the environment. All organisms living in an environment discard DNA, whether through waste, dead cells, carcasses, etc. and this can be picked up in trace amounts in water, soil, and even air. With Freshwater pearl mussels the hope is that DNA markers and techniques can be designed to allow detection of small or isolated populations of pearl mussels in rivers simply from a scoop of river water downstream of these prospective populations. There is also potential that the techniques could be used to monitor the size, health and population structure of these populations and perhaps even help identify sub species or genetically distinct populations. Whether this is possible or not, the possibility of cheaper and easier monitoring of pearl mussels fundamentally helps with conservation efforts.

I’m hoping to be able to keep Simon and the Esk Project up to date with our findings and perhaps provide some new information and techniques that may help the Esk’s own struggling mussels over time.

Anyway, that’s my little summary of things. I hope you guys found this interesting.

Thanks for reading, and keep on supporting the National Park,

Sam

Attritional conservation

Seas of Green – UPDATE

Last September we reported on the installation of black plastic sheeting on a couple of ponds in Bilsdale with the aim of shading out the non-native invasive plant species – New Zealand pigmyweed Crassula helmsii – which was accidentally flourishing there. The idea was to give the plant a taste of its own medicine by depriving it of light.

By two months the pigmyweed was becoming etiolated – pale and weakened due to the loss of sunlight – indicting the sheeting was effecting growth.

Crassula helmsii two months after black plastic sheeting applied. Copyright NYMNPA.

The sheeting was left on the two ponds through the winter and spring, and a second survey was carried out this July. The sheeting has killed off 100% of the pigmyweed that was covered, however pigmyweed plants remain around the edges of the ponds, where it was difficult to install the sheeting due to the surrounding vegetation and irregular shape of the pond edges.

One of the ponds covered by the black plastic sheeting July 2017. Copyright NYMNPA.

Contrast between the remaining Crassula helmsii at the edge of teh pond and under where the sheeting where the plant is now dead, July 2017. Copyright NYMNPA.The National Park Authority’s southern Apprentice Team will be spraying off the pigmyweed round the edge with a herbicide. The sheeting will remain on the ponds until at least late autumn to try to finish off this invasive species once and for all in this location, allowing the biodiversity of the ponds to recover.

Other non-native invasive plant species

New Zealand pigmyweed is one of the most common non-native invasive plant species found in England, along with Common rhododendron Rhododendron ponticum, Himalayan balsam Impatiens glandulifera, Japanese knotweed Fallopia japonica, and Giant hogweed Heracleum mantegazzianum. They were all introduced into the UK as garden plants. All of these species are present in the North York Moors to some extent, and work continues to control these particular plant species, without natural competition and predators, that can have such a detrimental effect on the area’s habitats and water quality.

We’re grant aiding the removal of rhododendron from important Plantation on Ancient Woodland Sties (PAWS), to help let in the light and give native ground flora a better chance of survival. Rhododendron can harbour the Phytopthora ramorum pathogen which is a great threat to forest species such as larch.

Himalayan balsam can be pulled out/cut down by hand but this needs to be done before the seeds are setting (August/September) because one shake of a plant can release 1000s of seeds that can travel up to seven metres potentially creating 1000s of new plants. Repeatedly removing the plants from a location before they can seed over a number of years will eventually mean this annual plant no longer regenerates there.

Japanese knotweed is trickier to tackle because it needs to be treated by careful herbicide injection. Repeated treatment can kill the rhizome which is so effective at spreading. The accidental breaking up of live rhizomes can spread the plant expediently. Careful disposal is vital.

We’re currently making best use of four years of funding from Yorkshire Water to tackle Himalayan balsam and Japanese knotweed along the banks of the Rivers Esk, Rye, Seph and Seven, through whole catchments and sub-catchments starting at the top. Both species are particularly menacing to river habitats as they out compete evergreen native species and die back in the winter leaving banks bare and prone to erosion increasing the sediment loads in the water.

Giant hogweed isn’t quite so common as the other plants in this area. It can be dangerous to deal with because its sap can burn skin so it needs to be treated with care. It can be cut down or tackled with herbicides, but like all non-native invasive species repeat control will be necessary to achieve eradication at a site.

There are lots of initiatives now across the country to address the threat of these out of place species, it can sometimes seem overwhelming but concerted repeated local efforts can have an effect.