Sea cliffs

Context

Vegetated sea cliffs are steep slopes fringing hard or soft coasts, created by past or present marine erosion, and supporting a wide diversity of vegetation types with variable maritime influence.  Exposure to the sea (wave splash and sea spray) is a key determinant of the type of sea cliff vegetation, although the amount of rainfall is also a contributing factor.  The most exposed areas support maritime vegetation dominated by a range of salt-tolerant plants.  More sheltered cliffs support communities closely related to those found on similar substrates inland, such as grassland and heath, with only a minor maritime element in the flora.
 
There is considerable geographical variation in sea cliff vegetation types across the UK.  Southern sites are rich in Atlantic-Mediterranean species, while northern sites support boreal species such as the endemic Scottish primrose Primula scotica.
 
Exposure is greatest on the south-west and northern coasts.  The long fetch associated with these coasts generates high waves and swell, and the prevailing winds help deliver salt spray to the cliff face and cliff tops.  The plant communities of the vertical hard rock cliffs in the north, which are exposed to the extreme exposure of the north Atlantic, are characterised by roseroot Sedum rosea and Scots lovage Ligusticum scoticum.  Cliffs may also support sea campion Silene maritima and thrift Armeria maritima and, in some rich areas, Arctic species such as purple saxifrage Saxifraga oppositifolia and moss campion Silene acaulis.  Cliffs are also important breeding grounds for seabirds like the kittiwake Rissa tridactyla, razorbill Alca torda, and guillemot Uria aalge.
 
In southern Britain the vegetation of hard rock cliffs tends to be formed by communities of thrift Armeria maritima, rock samphire Crithmum maritimum, and buck's-horn plantain Plantago coronopus.  The rare curved hard-grass Parapholis incurva, and the sea lavender Limonium recurvum may also be present.  The relatively sheltered, dry, calcareous cliffs on the south coast, are sites for the wild cabbage Brassica oleracea that grows on crumbling edges and sloping ledges.  This species is rare in Britain and is found in association with other rare species such as early spider-orchid Ophrys sphegodes and Nottingham catchfly Silene nutans.
 
SSSIs can be notified if they qualify under criteria outlined in Section 7 of Chapter 1 Coastlands of the Guidelines for Selection of Biological SSSIs.  In Northern Ireland, ASSIs are selected on a very similar basis – the Guidelines for the Selection of Biological ASSIs in Northern Ireland is an addendum to the SSSI guidelines rather than an alternative 
 

Summary statistics

  SAC A/SSSI Total
Favourable condition 66% 71% 70%
Main monitoring coverage E, S, W E, S, NI  
Reported assessments 35 145 180
Completeness of assessments 88% unknown  
Distribution of features     UK
 

Number of assessments reported by country and site type

Country SAC SSSI/ASSI
England 17 67
Scotland 13 70
Wales 4 0
Northern Ireland 1 8
United Kingdom 35 145
 

Natura features

List of Natura 2000 interest features within this reporting category

Interest feature name  
Formal name Informal name No. of assessments reported Total no. of features % assessed
Vegetated sea cliffs of the Atlantic and Baltic coasts Vegetated sea cliffs 35 40 88%
 
Natura 2000 comprises Special Protection Areas (under the Birds Directive) and Special Areas for Conservation (under the Habitats and Species Directive). The list presented here includes all of the qualifying interest features under these Directives, and shows the proportion of these features for which a condition assessment has been made.
 

SSSI features

List of SSSI and ASSI interest features in this reporting category

Interest feature name  
Formal name Informal name No. of assessments reported
Maritime cliff Maritime cliff 70
Maritime cliff and slope Maritime cliff and slope 8
Supralittoral Rock Supralittoral Rock 67
 
This list has not been fully standardised at a UK level yet. It is intended to show the principal constituent "feature types" for this reporting category.
 

Maps - distribution

UK distibution of reported interest features

Distribution of reported interest features.

Map showing the locations of the 10km squares in which at least one condition assessment has been reported. It does not show features that have not yet been assessed.

 

Maps - Natura

Distribution of SAC features showing assessments of favourability Condition of SAC features, with those currently reported as unfavourable-recovering shown as favourable
Current condition of SAC features
Distribution of SAC features showing assessments of favourability (where unfavourable-recovering is counted as unfavourable).
Condition of SAC features, with those currently reported as unfavourable-recovering shown as favourable
The implication of the unfavourable-recovering condition assessments is that at some point in the future these features should become favourable. This map shows the effect of that recovery by counting the favourable and unfavourable-recovering assessments together.

 

IMPORTANT NOTE: we do not have information on the timescale of the predicted recovery, which may be influenced by many past, natural and human related factors. A sustained sympathetic management regime is more likely to result in favourable condition being attained.

Key: Proportion of assessed features on 10km squares that are favourable:

Natura map legend - Key: proportion of assessed features on 10km squares that are favourable

 

Details of how these maps were produced

 

Maps - SSSI

Current condition of SSSI/ASSI features Condition of SSSI/ASSI features, with those currently reported as unfavourable-recovering shown as favourable
Current condition of SSSI/ASSI features
Distribution of SSSI/ASSI features showing assessments of favourability (where unfavourable-recovering is counted as unfavourable).
Condition of SSSI/ASSI features, with those currently reported as unfavourable-recovering shown as favourable
The implication of the unfavourable-recovering condition assessments is that at some point in the future these features should become favourable. This map shows the effect of that recovery by counting the favourable and unfavourable-recovering assessments together.

 

IMPORTANT NOTE: we do not have information on the timescale of the predicted recovery, which may be influenced by many past, natural and human related factors. A sustained sympathetic management regime is more likely to result in favourable condition being attained.

Key: Proportion of assessed features on 10km squares that are favourable:

SSSI map legend - Proportion of assessed features on 10km squares that are favourable

 

Details of how these maps were produced

 

Condition summary

Reporting category condition summary on Natura 2000 sites and SSSI

This lists the 10 different condition assessments and presents a bar chart showing the number of features within the SSSI series and the Natura 2000 series (either SPA for bird features or SAC for features other than birds). Note that for Natura 2000 we are able to estimate the number of features that have not been assessed during the 6 year reporting period - we are unable to do this for SSSI/ASSI because we do not have an overall list of notified interest features for these designations.

 

NB favourable unclassified and unfavourable unclassified have been used in this first six year cycle to get around difficulties in identifying trends in condition as common standards monitoring is implemented. It is expected that these categories will not be used for subsequent assessments of a feature.

 

Condition assessment - Natura 2000 features

The number and proportion of assessments for Natura 2000 (SAC and SPA) interest features falling into each of the condition categories
The number and proportion of assessments for Natura 2000 (SAC and SPA) interest features falling into each of the condition categories. Note that the �unfavourable� category includes all reports of unfavourable condition except �unfavourable recovering� which is shown as a separate segment.
 

Condition assessment - SSSI features

The number and proportion of assessments for SSSI/ASSI interest features falling into each of the condition categories
The number and proportion of assessments for SSSI/ASSI interest features falling into each of the condition categories. Note that the �unfavourable� category includes all reports of unfavourable condition except �unfavourable recovering� which is shown as a separate segment.
 

Adverse activities

The number of interest features where an activity has been reported as being implicated in the "unfavourable" condition of a feature
The number of interest features where an activity has been reported as being implicated in the "unfavourable" condition of a feature. More than one adverse activity may be reported for each feature.
 

Management measures

The measures summary bar chart lists the management measures relevant to the reporting category
For each "measure" the chart shows the number of interest features where that measure has been taken on a site to improve or maintain the condition of an interest feature. More than one measure may be reported for each feature assessed.
 

Interpretation

70% of sea cliff features reported are in favourable condition.  This is above the average for marine and coastal features, for all habitats features and for all features combined together.  71% of A/SSSI features and 66% of SAC features reported are in favourable condition.  A further 4% of A/SSSI features and 14% of SAC features reported are in unfavourable-recovering condition. 
 
Very few assessments had data on the reasons for unfavourable condition.  However, the most significant issues causing unfavourable condition involve habitat management.  Unfavourable condition is caused by under-grazing, invasive species and lack of remedial management.  Without grazing many areas will become rank grassland or overrun by scrub leading to a loss of quality of the habitat.  Sustaining grazing and scrub control programmes are complicated by the nature of cliff sites and problems related to stock and public access.
 
Management agreements are, however, in place for a significant number of features.  Ongoing or proposed coastal protection works continue to have an impact on sites; as these will stop coastal processes functioning and affect the quality of the habitat.  Sediment supply from eroding cliffs is also necessary to maintain littoral sediment features in many areas.