The Norfolk coast has some of the best examples of coastal sand dunes in the world. There are around 12,000 hectares of them in England and they can be found from Great Yarmouth all the way to The Wash. The dunes have a multitude of economic, recreational and biodiversity benefits for local residents and visitors alike. They provide a natural buffer against coastal erosion and flooding, they attract people to the area for leisure and recreation in turn provides a source of trade for local businesses and of course, they provide a valuable habitat to a wide range of rare and important species.
Sand dunes are naturally mobile and forever changing but the actions of people are causing changes to occur too quickly or preventing them from happening at all in some places. By creating coastal developments, golf courses and plantations, the movement of dunes backwards and forwards and along the shoreline is prevented. With global warming and rising sea levels this means there is simply less and less room for new sand dunes to develop; instead they get squeezed up against hard man-made infrastructure.
Man is also impacting sand dunes with pollution, but not just with physical objects on the beach. The rising nitrogen levels in the atmosphere caused by pollution, ultimately end up in the soil and favour faster growing plants and this means that the slower growing species get outcompeted quicker. This has caused a decline of around 50% in species richness in grey sand dune habitats. The physical actions of people (and their pets) also have a direct impact on sand dunes by trampling and damaging them.
The sand dunes of the Norfolk coast rise several metres above the beach and create a natural barrier between the sea and the land. With their prominent position they create a natural buffer that acts to absorb and deflect the strongest winds, waves and tidal surges.
In some places in Norfolk, the dunes were augmented by a concrete sea wall, following the 1953 tidal surge. In some places the dunes have grown behind and over the concrete sea wall (East Norfolk Coast), in other places, the dunes are part of an ever-changing coastal landscape, or dynamic dunes. Dunes play an important role in coast protection, providing a natural defence against flooding in time of storm events. They move inland and adapt to the sea, fluctuating over time.
On the East coast of Norfolk, some dunes have started forming in front of the sea wall, creating a new dynamic dune system. It is beneficial to let this natural buffer develop and monitor its evolution.
Did you know? Sand is formed through erosion of various types of shorelines (Cliffs etc.) elsewhere along the coast. Water does its job breaking the debris down into small particles: including sand. This is then transported to the beaches, and with the right wind direction, the dunes. During storm events, dunes are eroded and need time to recharge, and it is this natural process that can be ensured through mitigating human impact.
By striving to ensure dunes are both resilient and dynamic, and ensuring the biological succession between embryo (young dunes) and yellow dunes (mature dunes), it is possible to help protect the hinterland from flooding sustainably and cost-effectively.
To many the sand dunes may appear to be a monoculture of marram grass with little value for wildlife and biodiversity. However, this is far from the truth. There are four main stages of sand dunes, each of them provides a unique habitat that supports a wide variety of species.
The first stage of a sand dune, which is usually the closest to the sea is the embryo dune (young dune). This area is created when sand is blown across the beach and hits an obstacle. The resulting mound of sand is colonised by pioneer plant species such as Sand couch and Lyme grass and various strandline plants. During high tides these areas may become fully submerged preventing Marram grass, the species most associated with sand dunes from colonising. However, as the pioneer species grow, they collect more sand and sediment and soon the highest points of the dunes are above the high tide mark.
This is what is known as a Yellow Dune. The Marram grass colonises rapidly and with the build-up of sediment and nutrients, pioneer and strandline plants are overwhelmed and outcompeted. The marram grass stabilises the dunes and causes a chain reaction creating larger areas that are above the high-water point and thus suitable for more Marram.
However, as the dune gets higher and more sediment and sand builds up, it begins to act as a windbreak. This drop-in wind prevents further sand from building up and the habitat becomes less mobile, more sediment and nutrient builds up and the dune becomes less suited to Marram grass.
This is the next stage of a sand dune, which is knows as grey dunes. The higher stability and nutrient levels of these areas favours species such as Red fescue grass and the Marram grass begins to die out. The acidity of the sand in an area will determine what other species can colonise there. The dunes in North Norfolk are alkaline and therefore support a large variety of species including sand sedge and creeping willow whereas the dunes to the east of the county are more acidic and support less diversity.
With the varying shapes and contours of dunes, occasionally the wind may be channelled into certain areas of the grey dunes, this can sometimes cause a blow out to occur (a hole in the sand dug out by the wind) and if this goes below the level of the water table, a dune slack will be formed. These dune slacks create habitat for a wide range of species from willow trees to marsh pennywort, orchids, sedges and rushes.
The dune areas also provide a suitable habitat for many endangered and rare species of animal. For example, the dune slacks at the North Norfolk coast provide suitable breeding grounds for the nationally protected natter-jack toad, the dunes to the east create suitable nesting sites for globally endangered sea-birds and Horsey dunes are home to a large breeding colony of grey seals. For a relatively small area, the mosaic of habitats and conditions provided by sand dunes is second to none and their value for biodiversity is substantial.
In 2018 more than 8 million people visited the North Norfolk coast and many more visited the beaches and sand dunes across the east of the county. Many of these visitors came to enjoy the natural beauty of the landscape, hiking, walking and cycling along the coast and through the dunes. In North Norfolk alone, the value of this tourism is estimated at around £505 million, which supports more than 11,000 tourism related jobs. The tourism industry in Norfolk is growing each year which is brilliant for the local economy, but this does mean the fragile dune systems are under ever increasing pressure.
This is why Norfolk County Council are working as part of an international partnership to mitigate the impact of visitors on sand dunes.
What is Norfolk County Council doing to protect the dunes
Norfolk County Council will be working locally with stakeholders to identify main pressure areas, sensitive biodiversity and over-stabilising foredunes (too much grass coverage or becoming a grey dune too quickly whilst still close to high water mark – this signals an end to dynamism). We will then implement our action plans for each site in a joint approach with all stakeholders. We are currently carrying out trials at four sites along the North Norfolk Coast: Holme, Brancaster, Holkham and Horsey/Winterton. Using cutting edge science, design and innovation to create an action plan for each site.
These action plans are likely to involve some areas of the dunes being roped off to protect sensitive areas and species. These areas will be accompanied with information on why they are being protected alongside information directing you to areas that are fine to use, and some that we will actively be encouraging people to use. Information will be displayed throughout the dune sites and if you have any questions or queries, please feel free to contact a friendly local warden for further advice.
We will also be organising guided walks, outdoor science events and plenty of opportunities for you to raise any questions you may have on how your favourite dunes are being protected.
How can you help?
You can do your bit to help to protect Norfolk’s sand dunes so that they can continue to provide protection, biodiversity and recreation for years to come. Here is a list of do’s and don’ts when visiting the dunes.
Do:
Follow the information given on signposts and use designated areas and routes.
Keep your dog on its lead whilst walking through the dunes – it should be indicated where it’s fine to let them roam free!
Talk to the friendly wardens – they’re there to help.
Make the most of viewing platforms – enjoy watching wildlife from a distance which doesn’t scare them.
Take part in events organised on site by dune managers / ENDURE – we’d love it if you could help us to protect your dunes!
If you see litter, please help dune formation by removing it, especially on the strandline.
Don’t:
Ignore sign posts and use roped off, sensitive areas
Let your dog off its lead to run through the dunes – please wait until you reach the areas where dogs can be off lead with no risks to them or wildlife.
Do not get within 10 metres of the seals – they are weary of people and although they may seem cute and docile, they have large teeth and will bite if they feel threatened.
Approach nesting birds or their nests. Birds are terrified of us and our dogs. Please keep clear if you see any signs of nesting birds.
Light barbecues in the dunes. Dune fires cost our local fire services a lot of time and money every summer, and it impacts invisible biodiversity in our dunes.
Don't forget our dunes are very special. Our dunes are designated in one way or another because they really are Sites of Special Scientific Interest!