Bad news

Elizabeth A Clements – Deputy Director of Conservation, Head of Natural Environment

American Signal crayfish (Pacifastacus leniusculus), are an incredibly successful crustacean – but unfortunately this very success is bad for our aquatic habitats and native species.

Reports of the Invasive Non Native (INNS) Species American Signal crayfish had been getting closer to the North York Moors for a while. But recently the species have been identified within the National Park. Sadly they have been recorded in the River Rye catchment and also at Scaling Dam Reservoir which is connected to Staithes Beck and is close to the River Esk catchment.

There are currently up to six species of non-native crayfish in England, but the ones here now are the American Signal crayfish species from North America. There are a relatively recent arrival. They were imported into England/Wales in the 1970s to kick start crayfish farming ventures. But no one had quite realized what an entrepreneurial creature they would be in their own right, given new territory. They were soon out of control and have continued to be so ever since, marching menancingly on and spreading throughout the country. They can move up and down stream, between water bodies and watercourses, and over land for short distances crossing physical barriers. They can even survive out of water for a few days.

American Signal crayfish. Copyright Canal and River Trust.

Signal crayfish out compete other species and disrupt the interconnected biodiversity chain. They are particularly fertile producing up to 500 eggs in one go, and can live up to 20 years.

They eat fish and amphibian eggs, tadpoles and juvenile fish as well as aquatic vegetation. It’s not that they don’t have any predators, they do – otters, salmon, trout and eel can eat them – but they can reproduce in such large numbers that predation has little impact on the growing populations. Another adverse impact on the ecosystem is their habit of burrowing into banks to hibernate in the winter – banks are therefore weakened and more prone to erosion, increasing sedimentation and flood risk, and decreasing water quality.

In the National Park we are very lucky to still have a population of Britain’s only native freshwater crayfish the White-clawed crayfish (Austropotamobius pallipes). White-clawed Crayfish are declining throughout its range and are therefore protected by European and UK legislation. These native crayfish are declining due to competition, predation and disease. The American Signal crayfish are not only more aggressive and can tolerate poorer water quality and habitat conditions, but they also carry ‘crayfish plague’ (Aphanomyces astaci), a fungal disease which has devastating impact on our native species. Remaining populations of White-clawed crayfish are at risk of being wiped out once the Signal crayfish turn up.

White-clawed crayfish. Copyright Dan Lombard.

Researchers have been striving for years to find a way of successfully controlling and eradicating non-native crayfish but as of yet nothing has been successful so far. That research continues but out native crayfish are under threat in the meantime.  It’s not possible to safely exterminate a whole population in a connected watercourse or a large waterbody but many alternatives have been tried. Trapping and removing larger adult crayfish only allows the smaller younger population to thrive. Trials of chemical treatments have not yet been a success and in the aquatic environment have been particularly tricky. There have been attempts to remove adult crayfish, castrate them, and return them to the population in the hope they would control the population but that has not worked out yet either. Attempts have been made to erect physical barriers to prevent their free movement but only with very limited success. There is also a persistent rumour that people purposefully release Signal crayfish presumably to resuscitate the failed 1970s vision of crayfish farming.

It’s illegal to introduce Signal crayfish, that includes using crayfish as fishing bait – either dead or alive. A licence is needed in England to purposefully trap any species of freshwater crayfish, in an effort to assert some control over the situation.

The best thing we can all do at the present time is follow very clear biosecurity guidelines when we are in and around water.

Check, Clean, Dry campaign poster

It’s very important to note that people can unintentionally spread crayfish plague as well as the actual Signal crayfish but following the Check, Clean, Dry campaign is good practice and should help people avoid spreading the plague.

If you see any kind of crayfish please report these sightings to the Environment Agency (and the National Park Authority too).

We can all do our bit to help protect, conserve and enhance our native species populations in the North York Moors and beyond.

For further information see these JNCC, Buglife, and Natural England pages.

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

Habitat connectivity: evaluating potential

Roy McGhie – Conservation Project Assistant

Over the last month or so I’ve been investigating habitat connectivity in a new target area – near Boltby on the western fringe of the North York Moors.

Landscape from top of escarpment, near Boltby - copyright Roy McGhie, NYMNPA.

This particular area has a fantastic variety of habitats, from the arable plain on top of the escarpment, down the slope through Boltby Forest and across to the pasture fields in the west. Our overarching objective for this area is to strengthen the mosaic of habitats, with special reference to improving networks for butterflies and bats.

After my initial desk-based research I proceeded to ground truth the area to establish how much of our mapping and existing information was still accurate and to build up a current picture of the area. With so many public rights of way in the National Park exploring is usually pretty straightforward, but for closer examination of any particular area we would always ensure we have the land manager’s permission.

Felled veteran tree with dead wood left in situ (good for invertebrates, fungii and lichens) - copyright Roy McGhie, NYMNPA.

It’s important to establish what levels of connectivity already exist. Above the escarpment most of the arable fields are in Environmental Stewardship agreements, which suggests positive environmental land management is already in place and making use of national agri-environment schemes is something we would always encourage where appropriate for the environment and the land manager.

The Forestry Commission own a large forest within the area – Boltby Forest – and their Forest Design Plan sets out their long-term vision. This includes increasing the ratio of broadleaved trees to conifers and maintaining areas of open space. The open space is very useful in terms of meeting our original objectives for the area because open spaces in woodland create edge habitat which attracts bats.

Within Boltby Forest - copyright Roy McGhie, NYMNPA.

Another valuable habitat found within this area is unimproved and semi improved grassland, both acidic and calcareous in terms of soil pH because it’s where the farmland of the Vale of Mowbray meets the western edge of the moorland. Some of these grassland sites appear to be in a good condition and have an appropriate level of grazing to maintain this, whereas others seem more precarious.

Heath bedstraw and tormentil, indicative of an acidic grassland site - copyright Roy McGhie, NYMNPA.

Lots of wild thyme, commonly found on calcareous sites - copyright Roy McGhie, NYMNPA.The biggest threat to most of the grassland appears to be a lack of effective grazing. On several sites rank grass are beginning to dominate, resulting in wildflowers being outcompeted. On other sites scrub encroachment means that the grassland interest will diminish.

Rank grass and ash trees taking over a grassland site - copyright Roy McGhie, NYMNPA.

In a site where grazing is happening, there is occasional poaching (heavy ground trampling) by cattle alongside the small watercourse. This happens when stock congregate along particular parts of the bank to drink, or cross over.

Poached land beside a small beck - copyright Roy McGhie, NYMNPA.

Bracken is another issue in the target area. Bracken isn’t necessarily a bad thing – it can provide excellent cover for ground flora and butterflies such as the rare Pearl-bordered fritillary, but its tendency to spread means that it can very quickly outcompete and overcome other vegetation.

Bracken alongside a public footpath - copyright Roy McGhie, NYMNPA.

There are plenty of positive biodiversity hot spots in this area, including patches of habitat that are excellent for butterflies. There are also a number of established hedgerows acting as wildlife corridors for bats to navigate by.

Common blue butterfly - copyright Roy McGhie, NYMNPA.Small copper butterfly - copyright Roy McGhie, NYMNPA.

So once I’d assessed the area and its connectivity potential, I discussed ideas and options for how best to deliver the original objective with input from Rona, our Ecologist, and Mark, our Woodland Officer.

One of the key ideas coming out of these discussions is to provide long term replacements for the many mature in-field and boundary trees. These trees provide multiple benefits such as shelter for stock as well as a habitat for birds, invertebrates and insects. I recorded a standing veteran tree during my on-site survey and ideally we would like to see this tree fenced off as the stock in the field are causing considerable erosion around the base which may be weakening it.

To reduce the poaching alongside the watercourse we could help repair the fencing and investigate the use of a field trough so the cattle wouldn’t need to drink out of the beck.

Another idea is to fence off a particular area of mature ash trees to allow natural regeneration. This is because some ash trees show genetic resistance to the ash dieback pathogen, so whilst planting new ash trees is currently not encouraged assisting natural regeneration by older trees might mean that potentially disease resistant stocks are bolstered.

For the various grassland sites in the area, different management options are proposed. On the sites with bracken encroachment we could suggest organising volunteer tasks to help keep the bracken under control. On other sites we will need to discuss with the land manager their aims for their land and see if there is scope to manage levels of grazing to ensure the wildflower interest remains and potentially expands. Land manager engagement is a crucial part of the habitat connectivity development process – our management proposals on private land can’t happen without their permission and goodwill. Negotiations are the next step in the habitat connectivity process.

Overall I think this target area near Boltby is in a pretty well connected condition. There is already a mosaic of habitats suitable for bats and butterflies, and it forms part of a much more extensive network along the western fringe of the North York Moors. Our involvement will probably be relatively minimal, working where we can with local land managers to conserve the valuable grasslands and to sustain the important tree population into the future.

Landscape near Boltby - copyright Roy McGhie, NYMNPA.

 

Cosseting coastal streams

John Beech – Land Management Adviser

Over the winter months and tree planting season as part of our on-going quest to promote habitat connectivity in the North York Moors we’ve been working on coastal streams and linking up bankside (riparian) woodlands. There are a number of these coastal streams that run down from the east edges of the moorland plateau and don’t merge with a river but instead each continue east and end up running into the North Sea along the North York Moors coast.

Some of these coastal stream catchments have persistent water quality issues. By judicious land management and habitat stimulus we can combine the two objectives (extend habitat connectivity AND improve water quality) and make best use of available knowledge, skills and resources. Stabilising and fencing off banks to minimise sedimentation and to keep stock out of the water, along with buffering agricultural run-off, can have extensive impacts downstream and on the coast where the streams meets the sea.

Bankside tree planting underway - NYMNPA

This has been a real partnership effort. The National Park Authority’s northern work force – with any luck, skilled environmental workers for the future, the Northern Apprentice Team – strove through the mud and planted a good mix of native trees and shrubs, whilst land managers installed the fencing. Together we managed to fence over 600 metres of land and plant around 1,000 trees in gaps alongside the watercourses.

View of tree planting and fencing work near Mickleby - NYMNPA

Thanks to everyone who contributed to this work, not least the Environment Agency who paid for materials through their Tree Mitigation Programme.

This isn’t a solution in itself, but it’s part of an expanding effort to tackle water quality problems. For information on Defra’s available advice and grants – see Catchment Sensitive Farming.

A Toast to the Coast

John Beech – Coastal Project Officer

Turning plans into action

The eastern edge of the North York Moors National Park ends abruptly as it cascades over the cliffs onto beaches and shoreline and into the North Sea. As spectacular as any coastal landscape in the UK, our local coastline is a real gem.

Old harbour at Saltwick Bay used by vessels to transport materials for the Alum industry - John Beech

Careful planning is needed to look after our marvellous natural asset. As the local Coastal Projects Officer, I’ve spent the last few months working on a new coastal Management Plan that, if followed, should make sure our share of national treasure is looked after into the future.

HC boundary marker at Upgang, Whitby JBThe coastline between Boulby and Cloughton is not only in the North York Moors National Park but it also makes up part of the North Yorkshire and Cleveland Heritage Coast, one of 45 Heritage Coasts in England and Wales. These undeveloped scenic coastlines were defined in the 1970s by the (now extinct) Countryside Commission and they’re just as worthy of the special protection and recognition now as then. The Management Plan covers the whole North Yorkshire and Cleveland Heritage Coast (from Saltburn down to Scalby Mills).

Working on the new Plan has taken some time. We ran a public consultation over the summer to gauge people’s views on how to care for the coast into the future. Many of the responses chimed with what we were thinking but new issues and ideas were also raised regarding conservation, recreation, beach and water quality and coastal communities both by local people and national organisations – and these all needed considering and incorporating.

Cattersty Beach, Skinningrove - John Beech

The new Management Plan, which is due to be published in early 2015, will promote key principles to guide agencies and land managers and local communities working together as we move into the 2015 – 2020 period. To get an idea of what kind of thing we’re working towards – our previous Management Plan 2009 – 2014 is available on the North Yorkshire and Cleveland Coastal Forum website.

Our ongoing Coastal Forum is an active collection of people and organisations who have a vested interest and shared vision in the safeguarding and enhancement of a sustainable Heritage Coast. Back in September we organised our 12th annual Coastal Forum partnership conference. We had over 60 people attend to hear guest speakers from the Marine Management Organisation, Whitby Fishing School, Parkol Marine (shipbuilders), Whitby Whale Watching, Whitby & District Tourism Association and East Barnby Outdoor Centre. Due to the all-day sea fret (fog) we couldn’t get out to sea to look for whales in the afternoon but we did have an informative boat trip up and down Coastal Forum - a foggy day in Whitby Town the River Esk (no whales) and had a chance for a close up look at the Whitby harbour walls – impressive listed structures that were originally built in the 15th century.

If you’re interested in joining the Forum – get in touch.

Disused Alum Quarrries at Boulby - John BeechBack to the day to day stuff

In between developing and writing the new Plan, I’ve been working closely with the Environment Agency to improve the rivers and watercourses that run into the sea along the coast. In 2015, our bathing beaches at Staithes, Runswick, Sandsend and Robin Hood’s Bay will be subject to increased scrutiny as the EU Bathing Water Directive raises the bar on water quality. By working in the wider catchments now, addressing land management, we hope to give the beaches a better chance of reaching these new stricter guideline standards. So working with land managers we’ve been assisting with the fencing off of watercourses (and providing in field water sources) and planting beck side trees where there had been access points for cattle and breaks in the woodland cover. As well as the trees buffering the watercourses, the fencing prevents the livestock standing in the water and doing what comes naturally after a day’s grazing in the fields!

As well as addressing water quality issues this work also improves habitat connectivity by creating habitat corridors. We will also be back at farms in the Staithes Beck catchment in early 2015 to continue with some of the excellent work done last winter to promote habitat connectivity. We’ll be back planting hedges again at Roxby and Borrowby to provide these vital wildlife links between the coastal wooded gills there.

The Exmoor ponies on the coastal slope at Runswick Bay are currently off the undercliff for the winter. In the meantime our National Park Apprentices will set to and undertake some mechanical scrub control. Taking out the edges of the established scrub is part of the plan to encourage the seacliff grassland habitat to expand. The ponies have done a marvellous job over the summer tackling the scrub and will be back in the spring ready for some light grazing in 2015.Butterwort growing on cliffs at Beast Cliff Special Area of Conservation (SAC) - John Beech

The mixture of work that I do as the Coastal Project Officer is incredibly varied and thoroughly enjoyable and the opportunity to work in such a dynamic environment is something that I cherish every day.

Soggy moorland helping to stop soggy carpets

Rachel Pickering – Conservation Officer

I wish that my favourite view in the National Park was tucked away somewhere that nobody else knew about – but it isn’t.  Instead it’s one of our most photographed views – the Hole of Horcum within Levisham Estate. Not only is the view stunning but it has also proved to be a key location for landscape works towards the Slowing the Flow in Pickering project.

Work began on 8 January 2014 on the bund at Newbridge which will store flood waters upstream of Pickering. This work is a culmination of efforts by a number of partner organisations over the last few years to make changes to upstream land management to slow down the water running off the North York Moors and into Pickering Beck before it gets into Pickering town.  For the last three years the National Park Authority has been busy carrying out the following work on its own land at Levisham Estate.

Slowing the Flow - tree planting

Tree planting

Wooden dams created

Slowing the Flow - moorland gully blocking photo taken November 2012 - shows heather bales holding water back

Moorland gully blocking

  • The National Park Authority has spent £7,000 on partially blocking natural occurring moorland gullies with heather bales on various parts of the Estate.


Re-vegetation work

  • Heather brash has been spread in the Hole of Horcum to aid re-vegetation after the previous years’ bracken control left areas of bare ground.

Footpath repair work

  • An eroding footpath into the Hole of Horcum has recently been repaired with improved drainage that will slow down run off along the route.

Heather burning buffers

The hope is that with this type of beneficial land management established upstream of Pickering, along with the creation of the bund just to the north of the town, the chance of extreme flooding events will be lessened in the future.