Curing the bank erosion problems at Hilgay

Nick Carter, Wetland Project Officer
 

Bank erosion

One of the main tasks last winter at Hilgay was to fill the storage lagoon in stages up to the maximum level 1.59m above sea level. During the filling process the banks had to be checked to ensure there were no leaks or subsidence. The filling passed without incident but then the maximum level had to be held for at least a month while the checking continued. It was during this month, with the water at the same level, that wave action resulting from the south westerly winds caused some bank erosion along the northern banks of the two arms of the lagoon. The sandy soils prevalent in the area and the poor grass establishment added to the problem.

The erosion matting

A plan was hatched to solve the problem by using erosion matting over a layer of peat sown with a grass mix. The peat would ensure good growth of the grass which would help strengthen the integrity of the bank. At the bottom of the matting a line of reeds would be planted that would grow to form a natural barrier that would break up the action of the waves to reduce the erosion pressure. Fen Group was employed to deposit peat from the Methwold site, where they were already working, along the two eroded banks, 75-100m in length. The grass mix was sown and the two sets of erosion matting were laid over the top and pinned down in position. Well-developed reeds were sown by Broadwood Conservation, who had done reed planting on the Hilgay and Methwold sites this year, and then protected by chicken wire cages to prevent grazing by the resident wildfowl.

The grass has germinated in the mild conditions we have had so far this autumn and is becoming established through the erosion matting. The cages appear to be working in protecting the young reeds which should establish, which combined with the natural vegetation that has developed along the lowered shoreline should protect the bank. Water levels will be raised gradually during the winter to ensure the grass and reeds have the maximum time to develop while temperatures are still mild. The matting will prevent any erosion this winter and as it rots away it will be replaced by the hopefully well-established grass sward and the fringe of reeds.

Reminiscence and the Wild

 Eilish Rothney, Trinity Broads Warden

I recently had the wonderful experience of attending an evening performance at the new NWT Cley Marshes Simon Aspinall Wildlife Education Centre. The theatre group performed “Wanderlust” an assortment of tales and stories gathered from individuals around Norfolk. The evening held me spell bound as I heard tales of illness, tragedy and triumph woven together as a tapestry of life.

A common theme was people’s encounters with wildlife, wild spaces and the rural landscape. Breathing spaces for the soul, we often underestimate how the countryside and all its wonders capture our imagination, lift our spirits and invigorate our health. Research has shown that even looking at a picture of the countryside can help recovery from illness, so, how much more will even a gentle walk through some of NWT’s nature reserves do our health and well-being. So let’s get out there, even if the weather isn’t at its best, we can still make the most of our special places.

Check out the NWT website for information on reserves, guided walks, volunteering and of course other events and performances at the Simon Aspinall Wildlife Education Centre.

Here’s a couple of picks of my favourite places:

Filby Broad by Eilish Rothney

Filby Broad by Dickie Lay

 

Bat and moth evening with Norfolk Wildlife Services

Barry Madden, NWT volunteer

Smokey lines of straggly cloud silhouetted against an horizon of red and orange pastel hues; ragged streams of gulls silently and purposefully moving westwards towards their roost on the mud wastes of the Wash; shadow forms of rabbits hopping across the open grassland in the quickening dusk; and the fetid smell of rotting flesh emanating from stinkhorn fungi attracting flies to carry its spores to pastures new. 

Just a few impressions from an evening spent with NWT colleagues at the Mars Foods factory in King's Lynn helping to run a bat and moth evening for staff. First off we were given a tour of the site, extending over several acres, by Dave a most enthusiastic champion of all things wild and natural. He is working hard to develop the whole area into a wildlife haven and our job was to help spread some of this joy to other employees of the company.

But first some context. Mars Foods occupies a site on the Hardwick Industrial Estate in Kings Lynn, an industrial complex like many others scattered around our county and on first impressions the very antithesis of a wildlife friendly landscape. But let's look a bit closer. Behind the facade of iron fencing, beyond the tarmac car parks full of our expensive tin cans and rows of utilitarian warehouses lies another hidden world. A world that cannot be seen from the road; a world that by its very nature and because of its very location can remain largely undisturbed and peaceful. And it is here that enlightened staff, with advice and guidance from Norfolk Wildlife Services (NWS), are giving nature a helping hand, shaping what already exists into something better; creating something new from neglected tracts of otherwise sterile space. 
 
The space in question comprises small areas of mixed woodland and bramble scrub, tall boundary hedging and a large tract of open grassland some of which is being left un-mown to encourage wild flowers to flourish. The northern edge of the site is bordered by a small river, itself edged with mature trees, offering another dimension for wildlife to thrive. Log piles have been deposited in sheltered nooks, a pond has been dug, nest boxes positioned and a walkway created so that staff have somewhere to stroll during their breaks. It really is very simple, but so very effective.

Our primary concern this evening was to guide a small party of staff members on a bat hunt around the more wooded parts of the site. To this end we furnished each participant with a bat detector device that picks up the echo location calls of bats and converts them to electrical output that we humans can hear. Each species of bat emits signals at a particular frequency and by setting the dial on the bat detector to frequencies favoured by the common, more likely, inhabitants of the area their chatter can easily be picked up. It wasn't long before we were picking up the chipping calls of pipistrelles hunting around the top of a high hedge. At least three of these tiny winged mammals were present hunting mosquitoes and other flying insects of the night. On more than one occasion we were able to listen to the so called ‘terminal  buzz’, a series of increasingly rapid signals made as the bat zeros in on its prey. These emissions, very much akin to someone blowing a raspberry, are proof that ample food is present here and the bats were feeding well.
 
On one occasion we also picked up the slower more rhythmic call of a noctule bat, a much larger species sadly in steep decline over much of the country nowadays. Its presence here is therefore all the more welcome.

On then to the moth trap which tonight seemed to provide an irresistible lure for numerous crane flies that festooned the dew laden grass. Moths were few at this season and unfortunately we didn't have time to wait for the main emergence. However both large and lesser yellow underwings appeared as well as a few square spot rustics and a snout. A small taste late in the year of what the site could produce. Further trapping events are planned and will certainly produce many more species.

A most enjoyable and informative evening. The management and staff of Mars Foods must be congratulated for their excellent efforts in sympathetically managing this site for the benefit of people and wildlife. It doesn't take much you know; just an appreciation of the positive impact working with nature can bring to the workplace, a realisation that we are part of the natural world and not aliens within. Most importantly the boundless energy of committed individuals such as Dave to make it happen. NWT and NWS are proud to be part of this activity.

NWS can help your company too. For further details visit their page on this website.


Read Barry's own blog at http://easternbushchat.blogspot.co.uk 

Seeing the light

David North, Head of People and Wildlife

Almost by mistake I photographed the secret of life on earth.

Something that’s happening all around us, has been happening for millions - well probably billions - of years and without which there would be no us, and indeed not much life on the planet. And yet most of the time, though it’s happening all around, we simple don’t notice; it’s completely invisible and, as with so many other important things, out of sight means out of mind.

I’ve been on holiday and my wife and I, like lots of people, enjoy visiting gardens, so  we thought we would catch the fantastic East Ruston garden in all its autumn glory. To enter you walk past the plant sales area and it was there I photographed this secret. In a black barrel of water used, I guess, for watering the plants. I thought the pattern I could see in the water looked interesting so grabbed a  couple of images with a pocket digital camera and thought little more  about it. At least that was until I got home. And the image revealed on my laptop made me think... and then think some more. 

Wow, life is truly amazing. A miracle of life - and certainly the most vital of what these days are called ecosystem services - revealed. Quite literally a breath a fresh air! Have you guessed yet? Well the picture below, which is also rather beautiful, not because of  any great photographic skill, but simple because it’s a gateway into a miracle. The miracle of how the natural world sustains life on the planet. When we walk in nature we tend to see places and landscapes but rarely see the processes that sustain our lives going on all around us. 

So the image of course shows the everyday process of photosynthesis: green plants using photons of sunlight to quietly get on with the business of splitting water into its component parts of hydrogen and oxygen. The hydrogen gets used by the plants for making sugars (carbohydrates) in a process which neatly takes the ‘carbo’ bit from CO2. A neat trick if you can do it. And one which regulates our climate, mops up all that pollution that us animals breathe out (CO2), and at the same time creates the very stuff of life: food. ‘All flesh is grass’ as they say.

So three ecosystem services in one: mopping up CO2; producing carbohydrates in the form of sugars ( food for all animals); and the bubbles in the  image, giving us oxygen to breath. The oxygen coming from the O in H2O (not from the Co2).

Without photosynthesis life on earth would be impossible. All the oxygen in the air we breathe was part of a water molecule that green photoplankton, algae and plants have liberated. Green magic! This is alchemy of the very best kind. The process becomes visible when the plants - in this case filamentous green algae - release their waste oxygen (it’s the H they want to make sugar). As they are underwater the oxygen bubbles become visible.

Surely this is worth a moment’s reflection. If we could actually see these processes happening all around us – the oxygen bubbling up from our lawns, from the trees on our streets, from our nature reserves, parks and green spaces – then perhaps we would value nature more. But out of sight is out of mind. Like most of us I don’t usually think about  what’s truly happening around me, but this chance image made me reflect on this gift of nature, and even do a bit of research to refresh my understanding of photosynthesis. From space we may well be the blue planet but for us earth dwelling mammals it’s pretty much a green planet. And this green is the secret. Chloroplasts inside leaves working from dawn to dusk across the planet on a scale truly unimaginable busy keeping our planet a living one. I don’t know how much oxygen a hectare of green plants produces in a year but, through photosynthesis, a single hectare of wheat (that’s an area 100metres by 100metres) can take 10,000kgs of carbon out of the air from carbon dioxide and produce 25,000kg of sugars!

It’s a green world because the pigment (light absorbing material) chlorophyll is green: which means it absorbs red and blue light. Plants are green because they reflect green light which they don’t need for photosynthesis.

We are quite literally surrounded by this everyday miracle, but we simple don’t see it. We only see the anatomy of nature, of our Living Landscapes. We see places, and the natural communities they support, but we rarely see process. And of course its these processes – these ecosystem services, if you want to call them that – which keep us alive and keep our living world turning. If only we could see these processes then I believe our attitude to  nature would be so different. If we could see our planet’s atmosphere change colour as we pump more CO2 into it then I bet our attitude to this form of planetary abuse would be very different. Imagine it. See it. Imagine all those bubbles of oxygen rising from every tree and plant. From the ocean’s surface and its floating phytoplankton that we so rarely think about.  Imagine it. See it.

My eyes were opened by a barrel of greenish water at East Ruston. And an image, which, at least to me, looks like a whole strange universe. I wonder what other miracles of nature are all around me yet I’m blind to?

Alchemy

Sunlight and rain

Twisted through mystery

In green leaves

To power the world

 

Willow Emeralds return to Thorpe Marshes

Chris Durdin, NWT Volunteer at Thorpe Marshes

They can take a bit of finding, but it’s been a delight on some recent sunny days to see that Willow Emerald Damselflies are there again at NWT Thorpe Marshes on the edge of Norwich. Early autumn – late August to mid-October – is the time to see them.

Willow Emerald Damselfly, photo by Chris Durdin

A quick recap of the story so far. This damselfly is a recent UK colonist, first found in Suffolk in 2007. It's been at RSPB Strumpshaw Fen a few miles east of us for six years, and a colony at Cringleford found in 2013 has become well-known in the dragonfly world. Previously I said we found them at Thorpe Marshes last year, but it’s just come to light that an experienced observer also saw them here in 2013.

A useful tip is to look for them on a sunny, sheltered spot, on branches or other vegetation over a ditch with at least some open water. But they do have a knack of just melting away out of sight, so the highest count to date of ten damselflies is a minimum.

Ovipositing scars on a small willow,
photo by Chris Durdin

A peculiar feature is how eggs are laid into small cuts made in a thin branch, which leaves a distinctive, regular pattern (see picture). That branch is always over water as the eggs overwinter there and larvae drop into the water in the spring.

I have now found seven branches in various parts of Thorpe Marshes which have this proof of breeding and no doubt there are more, based on where the adult damselflies have been seen. It was a great pleasure to share that knowledge with NWT reserves staff on a recent site visit, so that this autumn’s management work can take the Willow Emeralds into account.

The work has just started a busy phase. Subject to ground conditions, marshes are being cut and ditches managed. Ponds, the ‘flood’ and the gravel pit – ‘St Andrews Broad’ – will be enhanced. None of this of this should have much impact on visiting, but keep an eye out for advisory notices. How lucky for me that my local patch should have the NWT’s expert attention.
 

Management at Thorpe Marshes is underway, photo by Chris Durdin

The management work at NWT Thorpe Marshes has been made possible by the Lafarge-Tarmac and Norse Landfill Communities Funds.

Chris Durdin leads monthly wildlife walks at NWT Thorpe Marshes. Details of monthly walks on http://www.honeyguide.co.uk/thorpemarshes.htm 

Coronation Meadows: a northern connection

Helen Baczkowska, Conservation Officer

In July, I spent a soggy week on Mull, the dismal weather thankfully balanced by the wonderful wildlife of the island – white tailed sea eagle, hen harriers, an otter family splashing on rocks, a late corncrake calling and, most exciting of all for a flower lover, the surprise of finding the Coronation Meadow for Argyll and Bute on the western headland of Tresnish.
 

Volunteers spread green hay at Fir Grove, photo Henry Walker, FWAG

The Coronation Meadows project, as many readers know, is a national initiative founded by HRH Prince Charles and working as a partnership between The Wildlife Trusts, the Rare Breeds Survival Trust and Plantlife. Coronation Meadows aims to reverse the decline in traditional hay meadows aims to create new meadows in every county of England, Scotland and Wales, using seed from existing flower-rich meadows.  

 

Rachael Long with Sulphur Clover
successfully established at Fir Grove
photo by Henry Walker, FWAG

In Norfolk, over the past three years, NWT has worked with the Farming and Wildlife Advisory Group (FWAG) to collect seeds for a group of road verges in the South Norfolk Claylands. These small nature reserves contain flowers such as cowslip and pepper saxifrage, dyer’s greenweed and the nationally scarce sulphur clover. The first of two new meadows, near Wymondham, is coming along well, with more wild flowers every year and a further new site in Diss, at the Quaker Wood community woodland, is also being established.

North of the border, on my one sunny walk of my holiday, the flora was quite different from that of the South Norfolk boulder-clays. The Haunn meadow, on Mull, is lime rich, on slopes facing gently westwards towards the Atlantic and exceptionally diverse.  Species I spotted included frog orchid, field gentian and greater butterfly orchid, along with yellow rattle, eyebright and devil’s-bit scabious.  Wetter area had bog asphodel and lesser spearwort, while nearby acidic areas had harebell and Lady’s bedstraw.