| Tayside Biodiversity - Tayside
Biodiversity Action Plan - Coastal - Maritime
Cliff and Slope |
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DEFINITION
Seacliffs form at the junction between the land and the sea where slippage or
erosion by the sea causes a break in slope. Gradient varies between 150 and vertical,
and in height and geology. Hard rock cliffs are eroded slowly by the sea and
are often near vertical, accumulating soil and supporting vegetation on ledges.
Soft rock cliffs are more unstable and often form a vegetated coastal slope.
The habitat contains an important range of natural features with
extensive areas of natural and semi-natural vegetation types - hard cliff with
rock face vegetation, cliff crevice and cave, rock exposures, coastal boulders,
boulder clay cliffs, scree and vegetated undercliff.
KEY SITES
There are two main areas of maritime cliff and slope in Tayside. Both of these
areas are largely designated sites:
Whiting Ness (next to Victoria Park in Arbroath) to Ethie Haven – most
of this is covered by Whiting Ness to Ethie Haven SSSI.
Rickle Craig (at the north end of Lunan Bay) to Scurdie Ness (just south of
Montrose at Ferryden) which is all designated as an SSSI. |
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CURRENT
STATUS AND EXTENT OF HABITAT
Over 50% of the cliffs in Britain are found in Scotland, but Tayside has less
than 1% of the Scottish total. More than half the Tayside coast is fringed by
sandy beaches with only two significant lengths of rock or degraded boulder clay
cliffs between Arbroath and Ethie Haven and between the South River Esk and Lunan
Bay.
The high diversity of species and plant communities relates to the considerable
habitat diversity and to the action and interaction of various ecological gradients.
These include variation in geology and soil types, influence of salt spray and
degree of exposure (including effects of wind), aspect (duration of exposure
to sunlight), grazing intensity and fertilizer inputs from adjacent farmland.
The sandstone cliffs of the Angus coast are relatively resistant to wave action,
but erosion in places may inhibit the establishment of some vegetation types,
whilst other plants are especially adapted to this environment. This erosion
also makes the area more interesting geologically.
Main Areas of Habitat in Tayside
The two main areas of maritime cliff and slope in Tayside are both designated
as Sites of Special Scientific Interest and are therefore fairly well documented.
Whiting Ness to Ethie Haven
This is the longest continuous stretch of sea cliffs and rocky shore in Tayside.
Up to 50m high and stretching about 11 km along the coast, the terrain is very
dangerous in places and many parts are inaccessible. The site covers the cliffs
and immediate hinterland from Whiting Ness to Meg’s Craig just south of
Auchmithie, and the cliffs and hinterland from Rumness, north of Auchmithie to
Corbie Knowe on the southern edge of Lunan Bay. The cliffs are widely studied
as they show a spectacular series of erosion features including sea stacks, blowholes,
caves, wave cut platforms and arches. Carlingheugh Bay has a raised beach and
relic sea cliff thought to date from the main postglacial transgression approximately
6,000 years ago. This part of the Angus coast is a well-known site for migrating
birds in autumn and winter. |
The site is a SSSI because
of its unimproved coastal grassland and large numbers of coastal
breeding and wintering birds, as well as for its geological interest.
Plants include
Long-bracted sedge Carex hostiana, Maiden pink Dianthus armeria,
Clustered bellflower
Campanula glomerata, and Hairy Violet Viola hirta and cliff vegetation
such as Sea spleenwort
Asplenium marinum and Pellitory-of-the-Wall parietaria diffusa,
together with some rare and
unusual mosses and liverworts. The site contains the largest
breeding seabird colony in Angus
with nationally important numbers of overwintering Turnstone
Arenaria interpres and Purple
Sandpiper Calidris maritima feeding and roosting on the flat,
rocky shoreline. Also present are
Kittiwakes Rissa tridactyla, Herring Gulls Larus argentatus,
Fulmars Fulmarus glacialis, Puffins
Fratercula arctica, Guillemots Uria aalge and Razorbills Alca
torda. Moth and butterfly species
include Grayling Hipparchia semele and Small pearl-bordered fritillary
Boloria selene, as well as
the nationally rare Small blue butterfly Cupido minimus. Rare
snails and beetles are also
present.
The Scottish Wildlife Trust’s Seaton Cliffs Reserve lies
at the south end of the SSSI. At 12.1
hectares, it is 8% of the total SSSI.
Two Geological Conservation Review (GCR) sites within the SSSI
have been notified. The first
of these is Whiting Ness where the exposures of the irregular
unconformity between the Upper
Old Red Sandstone and the Lower Old Red Sandstone demonstrate
that the stratigraphy of the
Midland Valley Devonian consists of two separate episodes of
sedimentation with a
sedimentary break between, the entire Middle Devonian being absent.
Secondly, fine coastal
exposures of the Ethie Lavas between Black Rock and East Comb
show margins that are
commonly pillowed and characterised by complex lava/sediment
relationships suggesting
extrusion of lava onto wet sediment. This site has important
research potential for studies on
Lower Devonian volcanic environments.
The Tayside RIGS Group has named the area from Whiting Ness
to Carlingheugh Bay a
Regionally Important Geological Site (RIGS). |
As well as the cliffs’ natural heritage and geological interests, there
are a number of ancient forts and castles designated
by Historic Scotland. There is also a rich history associated with the cliffs
between Whiting Ness and Ethie Haven from
Bronze and Iron Age occupation of some of the caves and Maiden Castle to use
of the caves at Dickmonts Den by
smugglers and wreckers. Places and events associated with the area were used
by Sir Walter Scott who described the
shipwreck of January 1800 in ‘The Antiquary’ and renamed Auchmithie
as “Musselcraig”, home of the “Mucklebackits”.
Rickle Craig to Scurdie Ness
Scurdie Ness to Boddin Point is a continuous length of rocky shore approximately
4km long.
This rocky
stretch of coastline was selected as an SSSI for its geological
interest and uncommon species-rich grassland types reflecting
the base-rich nature of the underlying rock - notably on and
around the old lime kiln on Boddin Point - and on the more friable
volcanic rocks. Characteristic plants include the scarce Nottingham
catchfly Silene nutans, as well as Kidney vetch Anthyllis vulneraria,
Clustered bellflower Campanula glomerata, Fairy flax Linum catharticum,
Carline thistle Carlina vurgaris and Burnet saxifrage Pimpinella
saxifraga. Small
areas of ‘perched’ saltmarsh are found around the
high water line. Over 30 species of snails are known owing to
the rich vegetation.
There are two Geological Conservation Review (GCR) sites within the SSSI. Scurdie
Ness to Usan Harbour provides the best section in Scotland through Old Red Sandstone
lavas and associated sedimentary rocks of the Montrose Volcanic Formation. These
rocks were formed about 410 million years ago with lavas being erupted from a
volcano to the north-east (the Montrose volcanic centre). During periods of non-volcanic
activity sediments containing pebbles of volcanic rock collected in lakes and
rivers flowing over the lavas. After the lavas had been erupted fluids flowing
through the rocks deposited silica in cavities, forming agates. The area around
Scurdie Ness is a GCR site in its own right for its mineralogy because of the
presence of these agates, some of which are gem quality, within the lavas. |
KEY
SPECIES
P = UK Priority species C = UK species of conservation concern
| Birds |
Shag |
Phalacrocorax aristotelis |
C |
| Herring gull |
Larus argentatus |
C |
| Turnstone |
Arenaria interpres |
C |
| Purple sandpiper |
Calidris maritima |
C |
| Kittiwake |
Rissa tridactyla |
C |
| Fulmar |
Fulmarus glacialis |
|
| Rzorbill |
Alca torda |
C |
| Puffin |
Fratercula arctica |
C |
| Guillemot |
Uria aalge |
C |
| Invertebrates |
Small blue butterfly |
Cupido minimus |
C |
| Small pearl-bordered fritillary |
Boloria selene |
C |
| Higher Plants |
Kidney vetch |
Anthyllis vulneraria |
|
| Pellitory-of-the-wall |
Parietaria judaica |
|
| Maiden pink |
Dianthus deltoides |
|
| Nottingham Catchfly |
Silene nutans |
|
| Lower Plants |
Moss and liverwort spp. |
|
C |
Mammals
Bat species may use the caves and clefts for roosting, breeding and hibernating. |
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