COASTAL SAND DUNES (UK BAP PRIORITY
HABITAT)
Summary
Coastal sand dunes occur where sand is blown inland from beaches and deposited above
the high water mark where it typically builds up into a series of low hillocks or ridges. They
are widespread along the Scottish coast.
Near their seaward edges, sand dunes are relatively young and ‘mobile’, with much bare,
unstable sand and just a patchy cover of pioneer plants. Further inland are older, more
stable ‘fixed’ dunes where the vegetation is more continuous and varies from species-rich
grassland to species-poor coarse grassland and sea buckthorn Hippophae rhamnoides
scrub. The hollows in between the ridges or hillocks are wetter ‘dune slacks’ with wetland
vegetation. Coastal sand dunes provide a rich habitat for birds, reptiles, insects, vascular
plants, bryophytes, lichens and fungi.
Coastal sand dunes are affected by grazing, encroachment by sea buckthorn, afforestation
(especially with pines and sycamores) and golf course development.
Grazing can be beneficial in maintaining species-rich fixed dune grassland. Control of sea
buckthorn, an introduced species, is undertaken in many places as a means of maintaining
the ecological interest of the open dunes. Afforestation of Coastal sand dunes should be
avoided. Golf course development should be planned sensitively so as to minimise
disturbance to this priority habitat.
What is it?
Coastal sand dunes occur along coastlines with extensive beaches of sand which dries out
when exposed at low tide, allowing loose sand to be blown inland by onshore winds and
deposited onto adjacent land above the high water mark. This deposited sand forms the
dune habitat. The sand typically builds up into a series of low hillocks or ridges interspersed
by hollows, so the topography can be complex on a small scale.
Near the seaward edge the dunes typically have a patchy vegetation cover and extensive
areas of bare, unstable sand. These are relatively young, ‘mobile’ dunes in the early stages
of formation and colonisation by vegetation. Typical plant species here are sand couch
Elytrigia juncea which commonly forms open pioneer vegetation in a narrow zone of
‘foredune’ at the extreme seaward edge, lyme grass Leymus arenarius which is common
generally along the seaward edge, and marram Ammophila arenaria which extends further
inland and dominates much of the mobile dune vegetation. The abundant tall tufts of
greyish-green leaves of marram give dune vegetation it’s most characteristic and familiar
appearance, but along the seaward edge L. arenarius is equally distinctive and eye-catching
because of its very broad bluish-green leaves.
Further inland the dunes become progressively older, more thickly vegetated and more
stable. Their vegetation consists of varied mixtures of species such as Ammophila arenaria,
sand sedge Carex arenaria, red fescue Festuca rubra and the moss Syntrichia ruralis ssp.
ruraliformis. The oldest and most stable dunes are referred to as ‘fixed’ dunes. Their
vegetation can resemble that of a neutral grassland with an abundance of species such as
F. rubra, lady’s bedstraw Galium verum, ribwort plantain Plantago lanceolata, bird’s-foot
trefoil Lotus corniculatus and white clover Trifolium repens, but also including some A.
arenaria or C. arenaria or both. Some fixed dunes have coarser, less botanically diverse
grassland of A. arenaria, F. rubra, false oat-grass Arrhenatherum elatius and cock’s foot
Dactylis glomerata. Others have scrub of sea buckthorn Hippophae rhamnoides which is
introduced in Scotland and most of the UK but native along much of the coast of eastern
England. The pH of the soils of fixed dunes varies from calcareous with herb-rich grassland
to more leached and acidic with dwarf shrub heath or mossy grassland.
The hollows within complexes of sand dunes are relatively poorly drained, so they commonly
support wetland vegetation and can even be flooded for much of the time in winter. They
are called dune slacks and their vegetation typically has some resemblance to an inland
neutral mire. Typical species include common sedge Carex nigra, silverweed Potentilla
anserina, marsh pennywort Hydrocotyle vulgaris, Yorkshire fog Holcus lanatus, Festuca
rubra, creeping bent Agrostis stolonifera, glaucous sedge Carex flacca, creeping buttercup
Ranunculus repens and the moss Calliergonella cuspidata. However, the presence of
creeping willow Salix repens in many dune slacks is a point of difference from a typical
inland mire.
How do I recognise it?
Coastal sand dunes account for most of the habitat in which coastal sand has been blown
and deposited onto adjacent land above the high water mark. The remainder belongs to the
Machair priority habitat (see notes below).
Differentiation from other Priority Habitats
The most similar priority habitats are Coastal vegetated shingle and Machair. Coastal
vegetated shingle is made up of a different set of NVC communities except for SD2 which
overlaps both priority habitats. Examples of SD2 on sand belong in the Coastal sand dunes
priority habitat; those on stony shingle are in the Coastal vegetated shingle habitat.
The separation from Machair is less straightforward owing to the more complex definition of
the Machair priority habitat. Amongst the areas of coastal wind-blown sand above the high
water mark, those belonging in the Coastal sand dunes priority habitat are those which do
not conform to the summarised definition of the Machair priority habitat given below the table
of NVC communities. The Coastal sand dunes priority habitat overlaps with the Lowland
calcareous grassland priority habitat, but this is only in the case of the CG2 grassland
community which is rare in Scotland, and quite simply, examples on coastal sand belong in
the Coastal sand dunes habitat.
In summary, in Scotland Coastal sand dunes priority habitat includes all examples of sand
dune NVC communities except SD1, SD3, examples of SD2 on stony or shingly ground, and
examples of SD7x and SD8a/c/d/e/x (as described by Dargie, 2000) which, for various
reasons (see below), may be assigned to the Machair priority habitat. Also included are all
examples of H11 Calluna-Carex arenaria heath in Scotland, and examples of CG2
calcicolous grassland and juniper scrub which are on coastal sand. Dargie (2000) describes
a range of other vegetation types that sometimes occur on sand dunes.
Definition in relation to other habitat classifications
Classification
NVC
Habitat types belonging to this UK BAP priority habitat
H11(all examples), SD2 (on sand; not on shingle strandlines),
SD4-19 (all examples except SD7x and SD8a/c/d/e in transitions
to machair priority habitat – see below), CG2 (on coastal dunes),
Juniper scrub on Coastal sand dunes (provisional NVC types
described by Dargie (2000)) and a range of other types in Dargie
(2000). H11, S2, S4-19 and CG2 are included in the Scottish
Biodiversity List.
In England this priority habitat also includes examples of H1
heath on sand dunes.
Phase 1
UK BAP broad
habitat
The Coastal sand dunes priority habitat includes two Phase 1
habitat types: B3 (example on coastal sand dunes) and H6 (all
examples).
All examples of the Coastal sand dunes priority habitat in Britain
belong in the UK BAP broad habitat - Supralittoral sediment.
Machair priority habitat = sites with the following characteristics: soil = blown sand with significant % of shellderived material, so lime-rich with pH >7; topography = flat or gently sloping ground at mature stage of
geomorphological evolution; marshy or flooded in winter; climate = cool, moist and oceanic; management =
influenced by grazing, cultivation, trampling or drainage within recent historical period; vegetation =
SD8a/c/d/e/x*, SD17, MG11 or Arable and fallow, with transitional areas characteristically including SD7x*,
SD8z*, Mx*, SxTHF*, SHv* or S19x* (* = provisional NVC types described by Dargie 2000).
Definition in relation to legislative classifications
Classification
Annex I
SSSI habitat
features
Habitat types belonging to this UK BAP priority habitat
This priority habitat includes all examples of Annex I types
H2110, H2120, H2130, H2140, H2150, H2160, H2170, H2190
and H2250, and dunes bordering H21A0.
The Coastal sand dunes priority habitat includes all examples of
one SSSI Habitat Feature: Sand dune.
Where is it?
Coastal sand dunes occur where coastal sand has been blown and deposited onto adjacent
land above the high water mark. These occurrences are mostly along ‘soft’ coasts with
sandy beaches rather than rocks and cliffs, but some dunes can occur where sand has been
blown some distance up rocky slopes or even steep cliffs. To the seaward side they typically
adjoin sandy beaches, though there can be a narrow zone of sandy or shingly strandline in
between the outer edge of the dunes and the upper edge of the sandy beach. In an inland
direction the sand dunes most commonly pass into various types of grassland, bracken,
scrub or woodland.
Coastal sand dunes are widespread along most parts of the Scottish coast. Information from
the Sand Dune Survey of Scotland indicates that there are at least 33,000 hectares of this
habitat in Scotland.
What is special about it?
As this priority habitat includes such a wide range of smaller-scale habitats ranging from dry
to wet and from almost bare sand to near-continuous vegetation, it is not surprising that in
total it includes much ecological interest in the way of birds, reptiles, insects, vascular plants,
bryophytes, lichens and fungi. Some species of special conservation status recorded in this
priority habitat in Scotland are listed below.
Group
amphibians
bees,
wasps and
ants
bees,
wasps and
ants
bees,
wasps and
ants
birds
birds
birds
birds
UK BAP
priority
list
EC
Habitats
Directive
Annex II
Scottish
Biodiversity
List
Epidalea calamita
y
y
y
moss carderbee
Bombus muscorum
y
y
red-shanked
carder-bee
Bombus ruderarius
y
y
wall mason
bee
Osmia parietina
y
y
Anser albifrons subsp.
flavirostris
y
Common
name
natterjack
toad
Greenland
white-fronted
goose
barnacle
goose
curlew
lapwing
butterflies
butterflies
butterflies
butterflies
flies
flowering
plants
flowering
plants
flowering
plants
flowering
plants
flowering
plants
flowering
plants
Branta leucopsis
y
y
y
Numenius arquata
Vanellus vanellus
Larus argentatus
subsp. argenteus
Alauda arvensis
Carduelis cannabina
Carduelis flavirostris
Emberiza calandra
Sterna dougallii
y
y
y
y
y
y
y
y
y
y
y
y
y
y
y
y
y
y
y
y
Aricia artaxerxes
y
y
y
Cupido minimus
Hipparchia semele
Lasiommata megera
y
y
y
y
y
Botanophila fonsecai
y
Astragalus danicus
y
Carex maritima
y
y
y
caraway
Carum carvi
y
y
y
stinking
goosefoot
Chenopodium
vulvaria
y
y
frog orchid
Coeloglossum viride
y
y
field gentian
Gentianella
campestris
y
y
herring gull
birds
birds
birds
birds
birds
Latin name
Red
Data
List
Wildlife
and
Countryside Act
(1981)
skylark
linnet
twite
corn bunting
roseate tern
northern
brown argus
small blue
grayling
wall
Fonseca's
dune fly
purple milkvetch
curved
sedge
y
y
y
y
y
Group
flowering
plants
flowering
plants
flowering
plants
fungi
fungi
lichens
lichens
liverworts
molluscs
mosses
mosses
mosses
mosses
mosses
moths
moths
Latin name
Juniperus communis
y
y
Monotropa hypopitys
y
y
y
y
y
y
yellow bird`snest
prickly
saltwort
dark-purple
earthtongue
datecoloured
waxcap
matt felt
lichen
a lichen
petalwort
cylindrical
whorl snail
matted
bryum
Knowlton`s
thread-moss
Baltic bryum
saltmarsh
thread-moss
sea bryum
rosy minor
lunar yellow
underwing
grass rivulet
slow-worm
sand lizard
common
lizard
a foliage
spider
a moneyspider
a moneyspider
baltic
stonewort
spiders
spiders
stoneworts
Red
Data
List
juniper
reptiles
reptiles
spiders
Scottish
Biodiversity
List
Common
name
moths
reptiles
UK BAP
priority
list
EC
Habitats
Directive
Annex II
Salsola kali subsp.
kali
Geoglossum
atropurpureum
y
Hygrocybe spadicea
y
y
Peltigera malacea
y
y
y
Toninia sedifolia
Petalophyllum ralfsii
Truncatellina
cylindrica
y
y
y
y
y
y
Bryum calophyllum
y
y
y
Bryum knowltonii
y
y
y
Bryum marratii
y
y
y
Bryum salinum
y
y
y
Bryum warneum
Mesoligia literosa
y
y
y
y
Noctua orbona
y
y
y
y
Perizoma albulata
subsp. albulata
Anguis fragilis
Lacerta agilis
Wildlife
and
Countryside Act
(1981)
y
y
Zootoca vivipara
y
Agroeca cuprea
y
Mecopisthes peusi
y
Silometopus
incurvatus
y
Chara baltica
y
y
y
y
y
y
y
y
y
y
How do we manage it?
Coastal sand dunes can be affected directly or indirectly by various forms of human activity.
Many dunes are grazed by stock such as sheep or cattle, and many are also accessible to
deer. Rabbits are also very common in this habitat. The vegetation of the more mobile
dunes tends to be little-grazed because the main species here are unpalatable to large
herbivores. On fixed dunes the vegetation typically includes some more palatable species
and is grazed at many sites. In such places grazing can be beneficial in maintaining
species-rich grassland of high botanical interest. In such places the removal of grazing can
lead to the development of taller, coarser, species-poor vegetation of lower botanical
interest, such as coarse grassland, bramble underscrub or sea buckthorn scrub.
Sea buckthorn, which is an introduced species in Scotland/much of Britain, can be very
invasive at the expense of other types of dune vegetation, thereby causing a reduction in
ecological interest and diversity. In many areas management is undertaken to cut back
encroaching sea buckthorn and keep other habitats open, especially where those open
habitats are of interest for uncommon small plants or for birds or invertebrates. This scrub
can, however, provide shelter and feeding habitat for birds such as wintering and migrating
passerines.
Areas of this priority habitat are best kept open and not planted with trees. Pines, sycamore
and various other trees and shrubs are able to grow successfully on the more stable parts of
sand dunes but they convert the open dunes into a habitat of lower ecological interest.
Some areas of sand dune have been affected by development as golf courses either within
or adjacent to the dune systems. Golf course development should be planned sensitively
where it comes close to this priority habitat. It can cause direct loss of dune habitat if dunes
are smoothed out or flattened, reseeded and converted into golf course greens and fairways.
There can also be losses or degradation of dune habitat as a result of paths or tracks
created for access to different parts of a golf course. Partial development of a dune
complex, as in scattered intensively managed greens and fairways surrounded by
unmanaged dunes, can break up the natural mosaic of small scale habitats within a dune
complex and thereby reduce the total ecological diversity.
References, links and further reading
Angus, S. 2004. De tha machair? Towards a machair definition. Scottish Natural Heritage.
www.snh.gov.uk/docs/B100728.pdf
Dargie, T.C.D. 2000. Sand Dune Vegetation Survey of Scotland: national report (2 vols).
Perth, Scottish Natural Heritage, (Contract No. SNH/032/95/AEB).
Ellis, N.E. and Munro, K. 2004. A preliminary review of the distribution and extent of
BAP priority habitats across Scotland. Scottish Natural Heritage Commissioned Report
No.044 (ROAME No. F00NA02).
http://www.snh.org.uk/pdfs/publications/commissioned_reports/F00NA02.pdf
Rodwell, J.S., ed. 2000. British plant communities Volume 5: Maritime cliffs, Sand dunes,
Saltmarshes and Other vegetation. Cambridge, Cambridge University Press.
Rodwell, J.S., Dring, J.C., Averis, A.B.G., Proctor, M.C.F., Malloch, A.J.C., Schaminee,
J.H.J. & Dargie, T.C.D. 1998. Review of coverage of the National Vegetation Classification.
Joint Nature Conservation Committee contract report F76-01-170. Coordinated by the Unit of
Vegetation Science, Lancaster University.
UK BAP 2008. http://jncc.defra.gov.uk/pdf/UKBAP_BAPHabitats-09-CoastSandDunes.pdf
Usher, M.B., Bain, C. and Kerr, A. eds. 2000. Action for Scotland's Biodiversity. Scottish
Biodiversity Group. Edinburgh, The Scottish Executive and The Stationery Office.
Common Standards Monitoring guidance: documents (pdf files) available to download from
http://www.jncc.gov.uk/page-2199
National Biodiversity Network (NBN) Gateway https://data.nbn.org.uk/
Scottish Government website – information about agricultural grants, subsidies and services:
http://www.scotland.gov.uk/Topics/farmingrural/Agriculture/grants/A-Z/Intro
Scottish Natural Heritage website: http://www.snh.gov.uk/
UKBAP information on JNCC website: http://jncc.defra.gov.uk/default.aspx?page=5155