Coastal Sand Dunes
Hills or ridges made from sand blown inland and deposited above the high-water mark, creating dynamic systems parallel to the beach. Becoming taller and more chaotic the further they are from the sea.
Vegetation zones change as the distance inland increases. The zones are influenced by time; dune stability; and local hydrological conditions.
Dunes can shrink due to storms, rising sea levels or a lack of sand.
Importance for wildlife
Sand dune systems provide a variety of habitat zones. Calcareous fixed dunes have a range of plant species including legumes. Acidic dune systems are dominated by heather. Creeping Willow and Mosses grow in the wet dune slacks. The more mobile sand areas provide open vegetation and bare ground which warms up quickly and areas of tussocky Marram Grass provide shelter. Solitary bees and wasps use stable sand dunes to make burrows for their larvae. Leaf-hoppers, plant-hoppers and ground beetles use the sparse vegetation between Marram Grass and Sand Couch.
Important associated species
Reptiles and Amphibians
- Natterjack Toad Bufo calamita
Bees and Wasps
- Brown-Banded Carder Bee Bombus humilis
- Large Garden Bumblebee Bombus ruderatus
- Sea-aster Colletes Bee Colletes halophilus
- Weevil Hunting Wasp Cerceris quadricincta
- 5-Banded Tailed Digger Wasp Cerceris quinquefasciata
- Rest Harrow Aplasta ononaria
- Silky Gallows-spider Dipoena inornata
- Heath Grasper Haplodrassus dalmatensis
- Sand Running Spider Philodromus fallax
- Antlion Euroleon nostras*
- Prickly Saltwort Salsola kali
- Field Scabious Knautia arvensis
- Campylium polyganum moss
- Viper’s Bugloss Echium vulgare
*Suffolk Priority species
Factors affecting habitat in Suffolk
- Sea level rise due to climate change. In addition to this, the south eastern area of the UK is gradually sinking due to the isostatic tilt of the mainland. This is also known as ‘post-glacial rebound’ and is the rise of land masses previously pushed downwards by the weight of the ice sheet during the last ice age approximately 10,000 years ago.
- Excessive pedestrian use may cause or exacerbate erosion. Sand dunes are usually easily accessible to the public.
- Sea defence structures and artificial stabilisation measures such as fencing can change sediment deposition and affect the dynamic nature of dune systems.
Habitat management advice
- Maintain a full range of successional stages with mobile fore-dunes, more established dunes with varied vegetation, stable sandy grassland or dune heath and dune slacks.
- Maintain undisturbed sparsely vegetated sand for ground-nesting insects as well as a variety of other habitats for feeding.
- Maintain flower-rich areas which will provide good quality foraging sites for bees and other insects. Legumes are particularly important.
- Maintain any transition areas with adjacent saltmarsh, fen or woodland. The mosaic of habitats will support a wide variety of invertebrates such as ground beetles and bees.
- Prevent damage by human disturbance, such as trampling e.g. by erecting fences and boardwalks where appropriate.
- Control dog-walking in particularly sensitive areas to prevent damage through fouling and trampling.
- Ensure continuity of scrub and woodland to provide shelter and nectar, but prevent the spread of scrub.
- Maintain dune slacks and natural fluctuation of water levels.
- Maintain any natural water features such as streams and seepages.
- Retain biodegradable tidal debris, such as seaweed and driftwood. These provide important habitat for invertebrates.
- Avoid over-stabilisation of dune systems.
Vision for Suffolk
- Improve knowledge of extent and quality of coastal sand dunes.
- Maintain the existing extent of coastal sand dunes to ensure no net loss.
- Re-create coastal sand dunes as opportunities arise.
- Encourage the restoration and improvement of degraded coastal sand dunes.
Where to find further information
- Buglife – advice on managing BAP habitats
- Buglife – Notable invertebrates (pdf)
- JNCC – Habitat Description (pdf)
- MAGIC website – interactive mapping information including designations
- Making Space for Nature, a Review of England’s Wildlife Sites and Ecological Network 16 Sep 2010. Chaired by Professor Sir John Lawton CBE FRS. Defra website (pdf)
- Natural Environment White Paper June 2011 – The Natural Choice: securing the value of nature (pdf)
- Radley, G.P., Sand Dunes - Part 1. England, 1994 ISBN 1 873701 19 5
- Suffolk Wildlife Trust – Habitats Explorer
* all the links marked (pdf) have been gathered into an Issuu stack
- Sand Dunes at Benacre by Paul Mitchell
- 5-Banded Tailed Digger Wasp by Paul Kitchener (Flickr)
- Dune Fescue by Charles Cuthbert (Flickr)
- Antlion by Pete Etheridge (Flickr)