Colouring in the summer

Abi Duffy – Conservation Trainee

Butterfly species are significant indicators for helping us understand the health of the environment and its ecosystems – that’s because butterflies respond rapidly to changes in habitat and climate. By recognising how butterfly populations are faring we can better appreciate how the wider environment is doing.

Butterflies and moths (Lepidoptera) also play a vital function as pollinators, as part of the food chain, and as a particularly beautiful and delicate facet of the natural world.

Small pearl bordered fritillary, North York Moors. Copyright NYMNPA.

In the North York Moors there are widespread generalist butterfly species such as Small Tortoiseshell Aglais urticae and Meadow Brown Maniola jurtina, but we also have  specialist butterflies such as the Duke of Burgundy Hamearis lucina and the Pearl Bordered Fritillary Boloria euphrosyne (note this is a different species to the Small Pearl Bordered Fritillary Boloria selene which is currently more widespread and also found in the North York Moors). Both the Duke of Burgundy and the Pearl Bordered Fritillary require very specific habitat to survive.

Habitat specialist butterflies are particularly sensitive to change. The Pearl Bordered Fritillary has suffered substantial declines in recent decades and so is now a UK Biodiversity Action Plan Priority Species. Its caterpillars feed upon violets, most often Common Dog Violets, and crucially the violets must be in a hot microclimate in order for the caterpillars to develop successfully over winter. Bracken litter is ideal at creating such a microclimate and so conservation of this species requires grassy habitat where bracken, scrub and violets are all present. In the North York Moors this butterfly species is found in only one location.

Small tortoiseshell, North York Moors. Copyright Abi Duffy, NYMNPA.

The Small Tortoiseshell, as a generalist, can cope with many different habitats but most often where nettles grow in abundance as the caterpillars feed upon the common and small nettle. This butterfly is one of our most widespread species, often glimpsed in gardens, but there is concern for a decline in species numbers recently due to the sensitivity of all butterflies to weather and climate.

Fluctuations in UK butterfly populations are common between years due to the different weather conditions through spring and summer. In 2017, the UK Butterfly Monitoring Scheme (UKBMS) showed the seventh worst year ever in UKBMS recording because a cold spring and wet summer causing butterfly species to struggle. It is expected that butterfly numbers should do better in 2018 because of the mainly dry summer, so far.

The UK Butterfly Monitoring Scheme looks beyond the short term and draws out the trends over time:

  • 57% of butterflies have been declining in abundance since 1976;
  • Both habitat specialist butterfly species and wider countryside species, in general, are declining;
  • Loss of, and the deteriorating condition, of habitats is attributed to declines in habitat specialist butterflies;
  • Encouraging recoveries have been seen in Duke of Burgundy and the Pearl Bordered Fritillary in some locations. Specialist habitat management has helped these species to recover in places;
  • For more widespread generalist butterflies the reasons for declines are not established yet.

Suggested reasons for declines in butterflies include more extreme climatic events, the ongoing loss and fragmentation of meadows, neglect of previously coppiced woodland and the increased use of pesticides. The paving over of gardens is also linked to declines particularly in towns and cities.

Certain lepidopterans, like the Painted Lady butterfly, migrate to follow the sun which is so important to butterflies. The movement and extents of particular species are now altering due to climate changes. Within Britain as the climate warms the extents of particular lepidoptera species are moving north where habitats and habitat connectivity allow.

Ringlet butterfly at Sutton Bank National Park Centre. Copyright Kate Bailey, NYMNPA.

Unimproved grasslands, including meadows, support more species of butterflies than any other single habitat in Britain. Grassland with low grazing or no grazing in the summer months allows wildflowers to flower and, very importantly, to set seed. A balance between grassland and natural scrub is helpful – scrub can provide shelter, respite, breeding areas and also a place for hibernation for butterflies. By managing such sites appropriately, unimproved grassland habitats can help sustain surviving butterflies.

MAD Volunteers clearing away some of the scrub from a Duke of Burgundy site - you can see the patches of primroses which along with cowslips are requirements for the species. Copyright NYMNPA.

But just like for bees, if you’ve got a garden with plants, you can help butterflies too. There are butterfly friendly nectar rich plants such as Buddleia, Lavender, Marjoram and Honeysuckle , and leaving fallen fruit to decay under your fruit trees provides sweet fruit juice for butterflies. If you’re lucky you might get to see a butterfly using its extraordinary tongue-like proboscis to collect the juice.

Peacock butterfly. Copyright Abi Duffy, NYMNPA.

Big Butterfly Count

Butterfly Conservation‘s annual butterfly count runs from 20 July to 12 August this year. The nationwide survey has become the largest butterfly survey in the world.  If you’d like to get involved visit http://www.bigbutterflycount.org/ which has lots of useful information and resources to help you.

An exceptional bog

Last year the Land of Iron commissioned an eco-hydrological assessment of Fen Bog(s) by consultants (Sheffield Wetland Ecologists).  An eco-hydrological assessment examines the workings of a water system and its wider ecosystems. Sunday was International Bog Day so to celebrate the complexity and variety of bogs – here is a very very simplified overview of that assessment. Any misunderstanding or misinterpretation is all mine.

View over Fen Bog. Copyright NYMNPA.

Background

Fen Bog(s) is at the top end of the Newtondale glacial channel in the east of the North York Moors. It’s part of the Newtondale Site of Special Scientific Interest (SSSI) and the majority of it is also designated as a Special Area of Conservation (SAC). Most of the site is a Yorkshire Wildlife Trust nature reserve, other parts are owned by the National Park Authority, the North Yorkshire Moors Railway and the Duchy of Lancaster.

Fen Bog(s) is a large peatland/wetland site, and according to the report “is of exceptional biological, palaeo-ecological and telmatological (to do with bogs) interest, especially as there are no comparable examples in the region or, indeed, in most of England”.

The bog happens to be within the boundary of the Land of Iron Landscape Partnership Scheme. The scheme focuses on the landscape area impacted on by the short but intense period of ironstone mining and railway development in the North York Moors. Intriguingly part of the Fen Bog(s) site has been subject to long-term modification since the Whitby–Pickering Railway line (now belonging to the North Yorkshire Moors Railway) was built alongside/across the site. The Partnership commissioned the report in order to get an holistic assessment of the existing data (of which there is a lot), and to identify the gaps and address these through additional field investigations, with the aim of increasing the understanding of the eco-hydrological functioning of Fen Bog(s) in order to help inform future management decisions. This management needs to conserve and restore its environmental value as well as allowing the continued functioning of the railway.

Historical Aspects

The Whitby & Pickering Railway was first opened in 1837, as a single-track, horse-drawn enterprise carrying freight between the two towns. Newtondale connects through the central moorland which largely separates the north and south of the North York Moros. Soon after the line was doubled and substantially rebuilt for steam propelled haulage with services starting in 1847.

Benham (An Illustrated History of the North Yorkshire Moors Railway, 2008) explains that Fen Bog(s) proved a “major headache” for the railway builders and that “Stephenson resorted to the same technique employed at Chat Moss when building the Liverpool & Manchester Railway. This involved stabilising the land by ‘pile-driving’ fir trees into the bog and overlaying them with sheaves of heather bound in sheep skin, together with more timber and moss.” In addition deep drains were dug alongside the railway through the mire to try and keep water off the track. The extensive drainage has tilted parts of the bog. It has also been suggested that it meant the bog turned from a topogenous system (source water mainly from the land) to an ombrogenous one (source water mainly from precipitation) – but the report considers this is unlikely. The railway’s embankments and sidings were built and maintained using railway ash, basic slag, limestone and basalt – all base rich materials imported onto the site which still have an impact.

The summit of the railway is a short distance north of Fen Bog(s), near the former location of the ‘Goathland Summit’ signal box. South of this the railway track skirts the western edge of the wetland, it is built mostly along the steeply-sloping edge so that its upslope side is on mineral ground or shallow peat whilst the mire side is over deeper peat. The railway line has therefore partly obliterated, truncated and drained much of the western edge of Fen Bog(s). Towards the southern end of Fen Bog(s), the glacial channel curves west and the railway here crosses the bog to the other side of the channel, thereby cutting across and separating parts of the Bog(s).

View of North Yorkshire Moors Railway crossing Fen Bog. Copyright NYMNPA.

Methodologies

Peatlands are strongly influenced by hydrology, chemistry, and vegetation.

The Fen Bog(s) report considers the hydrogeology including stratigraphy, surface profiles, and solid, wetland, and superficial (recent) deposits.

It also investigates the water supply in and the drainage out. All the different water features on the site are mapped – as pool, spring or seepage, stream/ditch with visible flow, water flow track, water filled ditch with no visible flow, damp channel, or seasonally wet channel. The main artificial drainage is associated with the railway including the drains on either side of the line, but there is also other historic drainage at the south end of Fen Bog(s) which was done to improve the land for agriculture.

Hydrochemical measurements were taken as part of the assessment to establish the current pH and also the electrical conductivity of the water at different points. There is a lot of variation across the site. It has been suggested that high pH readings i.e. alkaline are caused by leeching slag used in the construction of the railway track. Measurements from the recent assessment suggest that in terms of chemistry any effects of the trackway on the Bog(s) is either historic or localised. Because of the mix of chemistry Fen Bog(s) is classed as a Transition mire and this is reflected in its mix of vegetation (see below). The transition can be geographical or successional, or both.

There are a series of historic water table measurements at two specific points, from the 1970s to 1990s – one in ‘wet’ bog, rich in sphagnum, in the north, and one in relatively ‘dry’ bog, with a lot of heather, in the south. The report suggests the main reason for the more consistently higher water table at the northern monitoring point can be associated with the greater number and penetration of flow tracks across the mire, the number of groundwater outflows and a more consistent supply of telluric water (surface water and groundwater). Groundwater geology is always important in sustaining a high water table.

Looking into Fen Bog. Copyright Louise Cooke, NYMNPA.

Development and status

Much of the depth of peat at Fen Bog(s) is believed to sit in a hollow which decreases at its southern end. It has been suggested this hollow may have been a glacial or post-glacial lake. However it appears as if the mire developed on a dry surface, that is through paludification, and not by infilling a water body (terrestrialisation).

The lower layers of peat cores and sections collected contain the remains of tree species (Birch, Willow and Alder) and other plants (Reeds and Sphagnum) that suggest wet woodland. Then the higher up layers on top contain more plants and silt indicating the formation of swamp and a rise in the water level. This may be a consequence of wetter climatic conditions but also may partly be to do with human activity. There is an increase in non-tree pollen suggesting the removal of trees at the time, and the report postulates that the build-up of water on the site may have been due to it being artificially damned at the southern end. Sphagnum increases in the top level of peat, from c. 1100 AD atleat until the 19th century. The development of a Sphagnum-dominated surface on a reed-monocot swamp requires some isolation of the surface from more base-rich water sources which means the margins with inflow must have remained largely free of Sphagnum and a dome of peat therefore developed in the middle of the bog.

Fen Bog(s) can therefore be considered an embryonic raised bog, which has developed upon a protracted phase of reed–monocot peat that, because of the topography of the trough and the occurrence of marginal inflows, has been susceptible to flooding with telluric water until relatively recently. Because the system has developed across a shallow watershed, it can be regarded as an embryonic ‘sattelmoor’ (saddle bog). The report notes that this assessment is based on the centre and eastern margin of Fen Bog(s) – the western margin has been modified too much by the railway development and associated drainage to be useful as evidence. The modification led to a tilt of the mire’s surface towards the west.

Vegetation over time is the raw ingredients of a bog. The report reviews and updates current NVC vegetation classifications across the Fen Bog(s) site. It’s quite a mosaic. As well as non-mire vegetation such as dry grassland, bracken, dry heath and wet heath, there is also:

  • Weakly base-rich springs and soakways – base rich means a richness of chemical ions i.e. alkaline, a soakway is a narrow track of water flow where little or no water is normally visible. Supports plants such as Bog bean, Broad-leaved cotton grass*, Common butterwort*, and Black bog-rush*, as well as Sphagnum sp. and other bryophytes. Beyond the immediate Fen Bog(s) site there are base-rich springs and weakly base-rich soakways – where soils are acid rather than alkaline so it means the water ends up only weakly or not base-rich at all.
  • Acidic springs and soakways – supports plants such as Common sedge, Yorkshire fog and Marsh violet, as well Sphagnum sp.
  • Ombrotrophic bog – where the main source of water is precipitation. Supports plants such as Common cotton-grass, Cross-leaved heath and Bog myrtle.
  • Minerotrophic Bog – where the main source of water is watercourses and springs. Supports plants such as Purple moor-grass, Common yellow sedge and Carnation sedge.
  • Molinia mire – purple moor-grass dominated vegetation, also supports plants such as SundewsStar sedge and Bog asphodel
  • Nutrient-rich fen – these areas may be influenced hydrochemically either by base-rich springs, or by the base-rich material that make up the railway embankments/sidings. Supports plants such as Angelica, Tufted vetch and Water horse-tail
  • Carex rostrata fen – base-rich mire supporting plants such as Bottle sedge (this is the Carex rostrata), Marsh marigold and Ragged robin.
  • Pools and soakways with Carex limosa – supports plants such as Bog sedge* (this is the Carex limosa), Slender sedge*, and Bog pimpernel.
  • Wet woodland – these remaining woodlands are similar to that which began the formation of peat millions of years ago. Supports plants such as Grey willow, Downy Birch and Creeping buttercup.
  • Reeds and willow scrub – can also be classed as wet woodland. Supports plants such as Narrow buckler fern, Soft rush and Sphagnums.
  • Tall swamp and reedbeds – each at different stages of development with their own characteristics. One site which supports bulrush is presumably mineral enriched from the track ballast but this shows no sign of spreading out into adjacent vegetation without the enrichment. Another site, not yet colonised by willow scrub, supports plants such as Marsh pennywort, Water mint and Branched bur-reed.

* notable uncommon vascular plant species

Another view over Fen Bog. Copyright NYMNPA.

What next?

From the assessment the report goes on to outline the main management issues and to suggest restoration opportunities for the Fen Bog(s) site. These include vegetation control through gazing and fencing, monitoring the spread of reeds (Phragmites), clearing parts of the species poor scrub areas, retaining the wet woodland/scrub habitat, blocking and redirecting specific railway ditches, minimising the introduction of new embankment ballast material, and using engineered solutions to tackle subsidence problems. Interested parties will consider the recommendations and decide what is desirable as well as practically possible, in order to maintain this very important bog site that embodies a clash of natural and cultural heritage.

Postscript: There is a story that a steam locomotive sank into Fen Bog(s) at some point in the past, and remains there today. But this is just a story.

Local communities

Alasdair Fagan – Woodland Creation Officer

My job here at the National Park Authority means that I get the opportunity to be out and about in the North York Moors and get to places that most don’t get the opportunity to see. These hidden places are special for all sorts of reasons, in particular I get the chance to see some extraordinary woodlands – I admit I might be a little biased.

Recently we were out monitoring a woodland planting project near Castleton which meant we had to trek through a small existing woodland to get there. This was a combination of well-developed riparian (wet) flood plain woodland along river margins, wet marshy grassland filled with flowering plants and ancient woodland remnants creeping up the valley sides including oak, birch, hazel, alder and willow. Many of the woodland spring flowers were still in bloom and the woods were a lush green and bursting with insect and bird life.

Ancient Semi Natural Woodland site. Copyright Alasdair Fagan, NYMNPA.

As we approached the edge of this woodland I noticed something wriggling in the grass – it was a slow worm! Coming across this legless lizard species (Anguis fragilis) was a first time for me. Obviously I wouldn’t usually pick up/disturb wildlife but in this case I took the opportunity to move the slow worm to the cover of an old iron sheet as they are quite high up on the menu for many predatory species (birds, adders, badgers etc.).

Slow worm - copyright Alasdair Fagan, NYMNPA.

On the way back as we ducked, scrambled and tramped back through the same woodland I almost tripped over what can only be described as a large mound of leaf litter on the edge of a clearing. As I looked a little closer I noticed that the surface of the mound was moving – it was alive with wood ants! I was surprised to see them here as. I previously worked in Scotland and had always associated wood ants with more northern forest habitats. But they were definitely wood ants and they are surely an indicator that this particular woodland is in good ecological health.

Close up of a Northern hairy wood ant. Copyright Alasdair Fagan, NYMNPA.

Northern Hairy Wood ants (Formica lugubris) are a species of wood ant found in Scotland and in only two areas in England – the Peak District and the North York Moors. They are a fascinating species – I’m no expert yet but here are a few facts about our internationally important Northern Hairy Wood Ants:

  • The Northern Hairy Wood Ant currently has a near-threatened conservation status.
  • Northern Hairy Wood Ants ‘farm’ sap-sucking aphids (that favour oak and birch) for their honeydew. They gently stroke the backs of the aphids which then produce the sugar rich liquid in exchange for protection, and the ants use it to feed their young.
  • The ants take specific roles in the aphid farming process including; ‘shepherds’ who collect the honeydew, ‘transporters’ that move the honeydew to their nest, ‘guards’ that protect their aphids from competitors, and ‘scouts’ that search out new aphid colonies.
  • They employ a polydomous (many homes) nesting strategy whereby they have a number of nest mounds which operate as a single colony. The founding of additional nests allows for the expansion of the colony allowing it to grow and capitalise on new foraging and feeding opportunities spreading out through suitable habitat. If a smaller outlying nest is attacked or in danger then it will be abandoned and the inhabitants will return to the central nest.
  • Similar to other ants foraging workers leave pheromone trails, to good nectar sites or to groups of aphids, which direct other foragers to these valuable resources. The trails can persist for months.
  • The nest mounds of Northern Hairy Wood ants provide accomodating habitat for other invertebrates too. These include a variety of beetle species as well as the Shining guest ant (Formicoxenus nitidulus). This ant species lives within wood ant nesting colonies, accepting food from the host species and establishing its own discrete nests inside hollow twigs within the larger nest, raising its own brood. The Shining guest ant is a species of conservation interest, a priority species of the UK Biodiversity Action Plan and listed as ‘vulnerable’ on the IUCN red list.

Northern hairy wood ant nest - if you look carefully you can just make out the well camouflaged orange/black coloured ants. Copyright Alasdair Fagan, NYMNPA.

The intricacies of woodland ecology are often complex and astounding. My job means I work on woodland planting and creation and by the very nature of the timespan of trees I know that I’m likely never to see these new woodlands in their future glory. Therefore it’s very important to me to keep a perspective, looking at woodlands at a landscape and spatial scale and considering woodlands over their likely lifetime. Woodland visits like this one are what inspire me to want to create new woodlands and plant more trees, to establish the woodlands of the future.

If you might be interested in creating woodland in the North York Moors and would like more information about opportunities please contact me or call on 01439 772700.

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. 

 

Scrub, scub, glorious scub

Richard Baines – Turtle Dove Project Officer

If you are a farmland bird – such as a Turtle Dove or a Song Thrush, looking to protect your nest from predators and other disturbance – where should you nest? If you have any sense you will be looking for a dense patch of protective scrub or a large hedge (slightly more organised scrub) safe from dangerous raptor talons or avaricious eyes.

Unfortunately this type of vegetation containing older stands of Hawthorn and Blackthorn is becoming increasingly rare in the countryside due to creeping development, agricultural intensification and ‘tidying up’. Scrub can often be assumed to be a problem which needs to be removed. It has been an undervalued habitat in many conservation schemes over the years with other more showy habitats taking precedent.

The North Yorkshire Turtle Dove Project is wanting to improve the appreciation of this fantastic habitat.

Scrub is very important for Turtle Doves. Their delicate nests are often built within 2 metres of the ground in a dense tangle of thorns and twigs. They need this structure to reach the ground to feed. Stock grazing under such a habitat can remove any value to many birds such as Turtle Doves. In the winter scrub is a fantastic habitat for roosting birds such as Long-eared Owls. These magnificent birds are also looking for protection from disturbance and somewhere to have a daytime nap.

Last week we started work on our first community reserve for Turtle Doves at Sawdon near Scarborough. We were out with the Sawdon Community Nature Reserve Group and a very hard working Community Payback team. We planted a mixture of Hawthorn, Blackthorn and Hazel to create a thicket of scrub for the future. Luckily the planting day was sunny and warm with many birds singing in the trees around us. Amongst the appreciative audience were Song Thrush, Tree Sparrow and Yellowhammers who will all be able to benefit from the effort made to increase their local nesting habitat. Future plans for this site include pond restoration and a Turtle Dove flower meadow.

Creating our first community reserve for Turtle Doves - at Sawdon. Copyright NYMNPA.

Richard and Katie, helping to create our first community reserve for Turtle Doves - Yederick Spinney, Sawdon. Copyright NYMNPA.

Why why why the Rye?

Anne-Louise Orange – Ryevitalise Programme Manager

We’re continuing to develop our stage two application for submission in October to the Heritage Lottery Fund to support the Ryevitalise Landscape Partnership Scheme.

We need to explain and evidence why the upper Rye catchment is such a special area for people, wildlife, and the rich diversity of habitats the wealth of species rely on; and why it needs support to secure its future.

To help us we are delighted to have recently appointed the Wildfowl & Wetlands Trust Consultancy to undertake audience development and interpretation consultancy work for the Partnership. WWT Consulting are pleased too and have written their own blog post which you can read here.

We’re keen to hear from you if you have ideas and views about the catchment – please get in touch directly or complete our survey. Your ideas and views will be used to inform the delivery phase of Ryevitalise which, subject to a successful bid to the Heritage Lottery Fund, will commence spring 2019.

View of the Rye. Copyright Claire Flanagan, Environment Agency.

 

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

Updating the landscape

This is a good example of the time and effort it can take to change a landscape for the better.

The Trennet Bank Project was initiated back in 2013 (although the wish to do something here had existed for much longer than that). We’ve now achieved the major part of the planned work with the removal of conifers and the start of the gradual restoration of the site to moorland and native woodland.

Trennet Bank is on the eastern edge of Bilsdale West Moor, just west of the village of Chop Gate. Set on the top of the bank was Trennet Plantation, a 20 hectare 20th century conifer plantation (Sitka spruce and Lodgepole pine) planted on moorland in the late 70s/early 80s. Since then the plantation was identified as an inappropriate forestry development at this location in terms of landscape and environment. Because it was so high on the horizon it stood out on the skyline from a number of vantage points and because it was surrounded on three sides by important moorland (designated Site of Special Scientific Interest, Special Protection Area, Special Ara of Conservation) it was isolated from other woodland. In fact it stuck out like a sore thumb.

In addition, there was no future as a working plantation (plant-grow-fell) as it had become uneconomic to manage and harvest the timber, because of its location. So the trees would eventually start to be blown over leaving very little ground vegetation and therefore this would lead to erosion.

From a National Park Authority point of view Trennet Bank Plantation provided an ideal example of where to put into practice the North York Moors Management Plan policy – The removal of plantations from inappropriate sites will be supported where this will deliver landscape enhancement or other environmental benefits.

What happened…

The first requirement was the creation of a temporary access route from the plantation on the hillside down to the farm below and then onto the main road. This was a more achievable alternative to trying to take the trees up over the designated moorland. It meant building up the existing track including the provision of a new bridge so that the route could be used by timber lorries, and by machinery accessing the site to fell the trees. Subsequently once the conifer removal was completed the track was reinstated to ensure it was suitable for continued farm use. During and after the work, farm stock had to continue to be managed with fencing and gates, to allow the farm to function.

To remove the conifers a felling licence was required from the Forestry Commission. A felling licence requires a commitment to replant so there is no net loss of woodland. As the idea for Trennet Bank was to remove the existing woodland, the subsequent native woodland and wood pasture planned for the site wouldn’t amount to the required 20 hectares. Mark Antcliff, Woodland Officer, undertook the challenge to establish enough alternative planting sites in the wider area to ensure there was no let loss. In all, nearly 36 hectares of new compensatory woodland was established including on the plantation site and also in other appropriate locations such as bracken dominated moor edge, thanks to willing landowners and land managers.

With the access route improved and the felling licence in place the removal of timber started in the summer of 2015, and was completed by November 2016. The timber was of reasonable quality because the trees were over 30 years old and so could be sold on with some of the money made covering some of the costs entailed. The work also created large amounts of brash, some of which remains on the site to decay naturally and some of which was removed to be used as biomass.

In the winter of 2016/17 part of the felled site was replanted with oak and hazel, leaving the remainder (80% of the site) to naturally revert to heath and mire. The planted trees will need to be managed over the next three years to ensure they become established.

Establishing wood pasture on Trennet Bank. Copyright NYMNPA.

Lessons learnt for other potential large scale projects…

  • This turned out to be a major project for one Woodland Officer, with occasional assistance. A project of this scale and complexity would be helped by having a project manager on the ground.
  • Unavoidably the project relies on the good will and co-operation of landowners and tenants. It just couldn’t have happened otherwise.
  • In all, because of the complexity of the project, seven different agreements were required to be brokered by the Authority.

In the end a lot of time and resource was spent over a number of years, and as a result the landscape and environment of this part of the North York Moors has been significantly enhanced.

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

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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.

Talking about Turtle Doves

Richard Baines – Turtle Dove Project Officer

Our Turtle Doves are now in Africa, but that doesn’t mean our work stops.

Turtle dove courtship at Sutton Bank NYMNP Visitor Centre May 2015 by Richard Bennet, North Yorkshire Turtle Dove Project

With the majority of results now in for our two formal survey areas (Cropton and Dalby Forests), along with many additional sightings logged this year, we can now announce our results. In 2017 a total of 244 birds were logged over 78 dates between the first seen on 17 April and the last record of one on 25 September near Pickering. Over both the 2016 and 2017 survey seasons we recorded 24 singing males in Cropton Forest. During our 2017 surveys in Dalby Forest we found 12 singing males. Our largest flock was 13 birds including juveniles recorded on 25 July 2017.

These results illustrate how important our area is for these endangered birds. In comparison there were very few sightings in the rest of Yorkshire this year and even fewer to the north of us. We have known for some time our area has been a stronghold for this species due to the committed work of many individual birdwatchers and the local Forest Bird Study Group. However this is the first time Turtle Doves have been surveyed as a single species in the north of England. We would not have been able to achieve these detailed results without the hard work of our volunteer surveyors. I started this project as a volunteer myself, keen to help these beautiful birds and I hoped other people would feel the same. Thankfully a small army have now joined the Turtle Dove brigade! Here’s a quote from George Day, one of our volunteer surveyors this year; “Being part of such an exciting project has been fantastic. It’s been a real treat to spend dawn in the forest with purring Turtle Doves”.

Carrying out these surveys can be fun in themselves, but we are often asked what happens to the data collected and is there a direct benefit to Turtle Doves? Within the first six months of this project the data collected by volunteers so far has been used to identify and target the best areas to set up new feeding sites and attempt to improve nesting habitat. I can now visit a farm, explain to the land manager how important their land is for Turtle Doves based on how many birds are nearby. This makes a huge difference to the delivery of the project.

Richard presenting to an end of term meeting of Turtle Dove volunteers, Dalby Visitor Centre 2017. Copyright NYMNPA.

We’re working hard to spread the word and plan sites for new and improved habitat to create in 2018. I have a Heritage Lottery Fund target to deliver 40 talks to groups in the three years of the project and I’m pleased to be on course to complete 20 by the end of the first year! It seems a lot of people want to learn about and help these iconic birds. From a small village community in Sawdon to a national Forestry Commission conference the North Yorkshire Turtle Dove roadshow is purring its way around our beautiful county and beyond….

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