Survey of east Norfolk coast - Norfolk Biodiversity Partnership

Transcription

Survey of east Norfolk coast – identification of
BAP habitats and potential County Wildlife
Sites – 2007
Report produced by Norfolk Wildlife Trust
Ian Sharman
Reg Land
March 2008
Survey of east Norfolk coast – identification of BAP habitats
and potential County Wildlife Sites – 2007
1
2
3
4
5
Summary.........................................................................................................................................1
Need for survey...............................................................................................................................2
Scope...............................................................................................................................................2
Survey method ................................................................................................................................2
Definitions ......................................................................................................................................3
5.1 Maritime cliff and slope habitat. ................................................................................................3
5.2 Coastal sand dune habitat...........................................................................................................4
6
Characteristics and distribution habitats in Norfolk........................................................................4
6.1 Soft cliff .....................................................................................................................................4
6.2 Sand dune ...................................................................................................................................5
7
BAP actions relevant to this study ..................................................................................................5
8
BAP habitats and CWS criteria.......................................................................................................5
9
Findings ..........................................................................................................................................6
10 Conclusion .................................................................................................................................... 10
11 Recommendations......................................................................................................................... 10
12 Figures .......................................................................................................................................... 11
13 Field survey reports....................................................................................................................... 13
14 Photos ........................................................................................................................................... 26
GIS tables are provided on the attached CD covering the following sections
•
Hopton to Gorleston
•
Casiter to Hemsby
•
Eccles to Bacton
1 Summary
The survey area comprised three stretches of coast between Bacton and the Suffolk border that were
not currently designated as either SSSI or County Wildlife Site (CWS). The only section of coast not
surveyed was between Gt Yarmouth Haven mouth and North Denes. The survey was undertaken too
late in the year to undertake species recording for assessment against CWS criteria.
Two BAP habitats were present in the areas surveyed, namely, maritime cliff and slope (soft cliff) and
coastal sand dune (sand dune). Some of the maritime cliff and slope habitat may be better considered as
‘grassland and scrub’ due to the stabilised nature of the habitat. The total length surveyed was 17.4km.
Of this 7.9 km (16.3 ha) comprised BAP soft cliff and 3.6 km (27.3 ha) comprised BAP sand dune.
Over a length of approximately 1.7 km sand dune habitat was present at the base of soft cliff in the
form of climbing dune but this is included in the soft cliff total. A further 5.9 km were considered to be
too developed to support BAP habitat but nonetheless these stretches often retained remnant or pioneer
sand dune communities often in association with coastal defences.
It is recommended that 11 sections totalling 7.9 km of soft cliff and 2 km (16ha) of sand dune are
considered for designation as CWS with a further 2 sections comprising 1.6 km (11ha) of sand
dune requiring further consideration.
It should be noted that the sand dune communities in particular can change rapidly depending on
storms and there is evidence that the character of soft cliff is also affected over short periods.
Survey of east Norfolk coast to identify potential County Wildlife Sites (CWS) – 2007
1
The long term future of these habitats is intimately bound up with sea level rise and coastal erosion. An
assessment of the current shoreline management plan policies for each stretch is presented to indicate
potential conflicts with nature conservation objectives.
The survey achieves maritime cliff and slope BAP action 5.2.1 - Review CWS suite to identify new
sites for maritime cliff and slope. It also achieves the coastal sand dune BAP action 5.2.1 - Consider
additional areas for notification either as SSSIs or County Wildlife Sites by 2008.
The designation of these sections as CWSs will present significant problems not least the identification
of landowners and securing their consent to designate particular sites or parts of sites.
The Environment Agency should recognise the sections identified in tables 1 and 2 as BAP
habitats and treat them as if they are CWSs even if they are not formally designated as such. The
proposals in the current shoreline management plan largely represent a favourable management
outcome for the sections identified, at least in the medium to long term, but the biodiversity value
of the sections should be considered in any works undertaken.
Funding for the report came from Environment Agency and Norfolk Biodiversity Partnership.
2 Need for survey
The need for this study arose out of a recognition that the there were a number of sections of the coast
that were not covered by specific nature conservation designations eg SSSI or CWS but which
nonetheless contained BAP habitats. These habitats were potentially under threat from unsympathetic
development from both the leisure industry and coastal flood defence works. In addition the intense
pressure on these habitats presented significant management problems which were not receiving
adequate attention. The coastal strip has been recognised as a core area for biodiversity in the Norfolk
ecological network and this survey sought to confirm this recognition by identifying the key areas for
biodiversity. Finally, the lack of any designation on these areas often resulted in them being ignored
when ecological assessments or surveys were undertaken hence there was an historic lack of
information about the areas.
3 Scope
The survey had the following objectives
• Field survey of BAP habitats outside of areas that are currently designated as SSSI or CWS
between Bacton and Suffolk border
• Identify potential CWSs for further investigation.
• Delineate BAP habitats on GIS layer
• Produce a short report
4 Survey method
Two BAP habitats were known to be present in the areas surveyed, namely, maritime cliff and slope
(called ‘soft cliff’ below) and coastal sand dune (called ‘sand dune’ below). Some of the soft cliff
habitat is probably better considered as ‘grassland and scrub’ due to the lack of active erosion resulting
in the creation of early successional habitats. In some areas sand dune occurs on the soft cliff.
The initial survey to identify the BAP habitats present was undertaken in October 2007. This was too
late in the year to undertake a botanical survey of the habitats and thus provide information for
identifying CWSs.
The total length of coastline surveyed was 17.4. The only section of coast without SSSI or CWS
designations that was not surveyed was between Gt Yarmouth Haven mouth and North Denes (5km).
Sections of coast were delineated based on general characteristics – BAP habitat present and presence
of built development. A land use survey of the hinterland to the coastal habitats was undertaken using
the Phase 1 Habitat Survey Methodology1. A hand drawn map was produced showing the phase 1
1
Handbook for phase 1 habitat surveys: a technique for environmental audit. JNCC 1993
2
habitats along with target notes. The land use was not mapped on MapInfo GIS; however, significant
areas of undeveloped land abutting the coast were mapped as a layer. In addition photographs (see
section 13) were taken to show the general character of sections (these were not fixed point and do not
necessarily show all relevant features of a section). Information is also provided on the nature of the
coastal defences. The hand drawn maps and target notes are in section 12. NB the reference numbers
used in the target notes are not those used on the final report GIS layers.
A maritime cliff and slope inventory has been carried out by Natural England2 however whilst
identifying the extent of the habitat it provides little information on the quality of sections of coast
covered in this report. The boundaries of the survey sections in this report were compared with those in
the NE report and had a high level of agreement.
This final output comprises a final report (pdf), 3 JPEG files for figures 1-3 of the report and MapInfo
tables for soft cliff and sand dune boundaries, coastal defences and undeveloped land for each of three
sections (Hopton-Gorleston, Caister-Hemsby and Eccles-Bacton. It is recommended that these tables
are viewed in association with County Wildlife Site and SSSI boundary data (not supplied). The report
has been circulated to:
• NBRC
• Norfolk Biodiversity Coordinator
• Environment Agency Eastern Area
• North Norfolk District Council
• Gt Yarmouth Borough Council
• Natural England Norfolk-Suffolk team
5 Definitions
5.1 Maritime cliff and slope habitat.
The national BAP3 provide a very general definition of the habitat:
‘Maritime cliffs and slopes comprise sloping to vertical faces on the coastline where a break in slope is
formed by slippage and/or coastal erosion. There appears to be no generally accepted definition of the
minimum height or angle of slope which constitutes a cliff, but the zone defined as cliff-top should
extend landward to at least the limit of maritime influence (ie limit of salt spray deposition), which in
some exposed situations may continue for up to 500 m inland. On the seaward side, the plan extends to
the limit of the supra-littoral zone and so includes the splash zone lichens and other species occupying
this habitat.’
NB The soft cliffs spray zone in Norfolk is often absent and only a narrow zone of maritime grassland
may exist.
The soft cliff BAP habitat is characterised by successional variation from bare ground to stable
grassland and even scrub. The succession is constantly being reset through slope failure caused by
rotational slides, slumping or erosion of the toe by high tides and storms. This results in a wide variety
of slope aspect and exposure and associated wet and dry facies. Additional features are cliff top
grassland and at the toe of the cliff embryonic dune or even substantial areas of climbing dune.
An additional factor that affects the quality of a particular section is the presence of cliff top
development eg houses or caravan sites when significant quantities of rubbish, garden debris and even
rubble can be found on the cliff4.
2
Maritime cliff and slope inventory 2004/5. Hill, Downes and Harfoot. Natural England Research
Report 003. http://naturalengland.communisis.com/naturalenglandshop/docs/nerr003.pdf
3
Habitat Action Plan for Maritime cliff and slope http://www.ukbap.org.uk/UKPlans.aspx?ID=27
Buglife
http://www.buglife.org.uk/conservation/adviceonmanagingbaphabitats/maritimecliffsandslopes.htm
4
3
There is also a time dimension in that sections of cliff that are currently showing a good range of
features, such as varying rates of vegetation colonisation, can become subjected to high rates of erosion
that remove these features. The November 2007 storms resulted in the removal of large sections of
embryo dune and increased erosion of cliff faces changing their character significantly.
5.2 Coastal sand dune habitat.
The national BAP provides a general description5. Sand dune vegetation comprises a number of zones.
A simplified zonation has embryonic dunes, often ephemeral, occurring on the seaward side. They
support very few plant species, the most characteristic being marram grass Ammophila arenaria. Semifixed or yellow dunes occur where the rate of sand accretion has slowed but the surface is still
predominantly bare sand; marram is still common, but there is an increasing number of other species.
Fixed dune grassland forms largely closed swards where accretion is no longer significant, the surface
is stabilised and some soil development has taken place. Calcareous fixed dunes support a particularly
wide range of plant species. Acidic dunes which are heavily grazed by rabbits may support lichen
communities. No dune systems in the survey contained slacks.
A feature of some sections was climbing dunes, where sand is blown up on to higher ground, often
onto maritime cliff and slope.
A feature of the sand dunes in the survey area is that they often occur in association with sea defences,
often forming on top of sea walls. They are all backed by developed land and so the transition from
embryo dune to grassland rarely occurs. An additional factor is the rapid change to habitats that occur
following storm events when, for example, embryo dune can be completely removed from sections of
coast. In addition sea defence works for example at Bacton have apparently destroyed embryo sand
dune and dune grassland (this damage may be short term depending on future management and coastal
deposition).
6 Characteristics and distribution habitats in Norfolk
6.1 Soft cliff
The Norfolk BAP states:
‘Soft cliffs composed of glacial sands and clays with rafts of chalk occur on most of the coastline
between Weybourne and Happisburgh with an estimated length of 22.7km. A few short sections also
occur further south. They tend to separate into those with predominately vertical cliffs as at Weybourne
and Happisburgh and those with extensive areas of slumping as between Cromer and Mundesley.
Extensive areas of grassland are associated with the slumping cliffs covering an estimated 129ha.
Seepages are an important feature of the cliffs between Cromer and Mundesley and to a lesser extent
between Sheringham and Cromer. Cliff top grassland is present …… between Weybourne and
Mundesley sometimes as golf courses or caravan sites. Eastwards the land is generally cultivated to the
cliff edge.6’
Soft cliffs mentioned in the BAP that relate to this survey area are
Mundesley – Bacton
part SSSI
interest
geological
characteristics
soft slumping
Ostend- Happisburgh
part SSSI
geological
soft vertical
?
soft vertical
Scratby
5
Habitat Action Plan for Coastal sand dune http://www.ukbap.org.uk/UKPlans.aspx?ID=28
6
Norfolk HAP Maritime cliff and slope
http://www.norfolkbiodiversity.org/actionplans/habitat/maritimecliffandslopes.asp
4
The BAP description does not recognise the full extent of BAP soft cliff habitat in Norfolk as it largely
focuses on those areas designated as SSSI or SAC.
6.2 Sand dune
The Norfolk BAP states:
‘Estimates of the total area of sand dunes in Norfolk vary considerably. Radley has given the total area
as 1,091 ha; however, this figure does not include the dunes at Stiffkey, nor does it include the stretches
of dunes from Cromer to Paston and Sea Palling to Horsey. When these areas are added to Radley’s
figure, the total area of sand dunes in Norfolk is estimated to be approximately 1,200
ha. Some fore dunes occur at the foot of the soft cliffs between Cromer and Paston. A further stretch
starts south of Sea Palling and extends in a single artificially managed ridge to Horsey where it
broadens into the Horsey-Winterton ness system. Dunes then occur intermittently on the coast to
Caister where a smaller ness system is developed which then extends south to Great Yarmouth.
There are a number of other areas which are designated as County Wildlife Sites, mostly between Sea
Palling and Horsey. However, between Hemsby and Caister, the remnant dune system is not protected
by conservation designations.’ 7
The BAP description appears to represent the current situation regarding the distribution of sand dune
in Norfolk.
7 BAP actions relevant to this study
This survey will generally contribute toward the delivery of the following sand dune BAP objectives
• Maintain the existing area of dunes (estimated at approximately 1,200 ha), subject to natural
change.
• Restore natural functioning to dune systems where at present constrained by sea defences (eg
Winterton to Sea Palling) and facilitate dune roll-back. (This is a long-term aspiration).
• Enhance connectivity between dune systems by enhancing remnant dune systems and creating
ecotones between dunes and inland habitats
This survey will achieve BAP action 5.2.1 Consider additional areas for notification either as SSSIs or
County Wildlife Sites by 2008.
This survey will generally contribute toward the delivery of the following soft cliff BAP objectives
• Maintain and where possible enhance the maritime cliff and slope in Norfolk.
• Increase the area of cliff top grassland by arable reversion.
The survey will achieve BAP action 5.2.1 - Review CWS suite to identify new maritime cliff
sites.
8 BAP habitats and CWS criteria
There are no specific CWS criteria for identifying soft cliff and sand dune sites. In the absence of
agreed criteria the procedure is to assess each site against the so called Radcliffe criteria. These criteria
are naturalness, diversity, size, rarity, typicalness, fragility, potential value, intrinsic appeal.8
It is suggested that when using the Radcliff criteria the identification of soft cliff BAP habitat for CWS
designation takes account of the following physical parameters
• Presence of naturally functioning shoreline or proposed in Shoreline Management Plan9 (for a
particular stretch the preferred policy option is ‘no active intervention’ or ‘managed
7
Norfolk HAP Coastal sand dunes
http://www.norfolkbiodiversity.org/actionplans/habitat/coastalsanddunes.asp
8
See Norfolk County Wildlife Site Handbook NWT 2007 & Nature Conservation Review Ed D
Ratcliffe. CUP 1977
9
Shoreline Management Plan Sediment Sub-cell 3b Halcrow 2007
http://www.northnorfolk.org/acag/default_2092.asp
5
•
•
•
•
•
realignment’ policy from at least the ‘medium term’). Natural functioning, however, may be
currently operating even in the presence of a wide variety of coastal defences.
Large proportion of bare ground caused by any of the following - slippages, mudslides,
seepage, surface and wave erosion
Successional grassland communities from recently colonising (open and sparse) to mature,
closed swards and scrub
Variation in slope angle, aspect and micro topography, caused by slumping and slippage, and
a range of features from cliff top to beach eg debris lobes on beach
Presence of damp to wet habitats eg presence of reed patches (Phragmites) on cliff slope and
standing/running water
Presence of cliff top grassland and/or dune vegetation at base of cliff
It is recommended that extensive sections of rapidly eroding soft cliff with little or no grassland
development are not considered as BAP habitat.
In some areas the soft cliff is dormant and vegetation is predominantly stabilised. These areas may be
better considered as unimproved grassland and scrub habitats. They may represent a significant
resource of these habitats locally, especially when their length (as opposed simply to area) is
considered. These sites may often represent the most significant areas of unimproved habitat in some
coastal areas. Potentially these dormant soft cliffs could be reactivated by increased erosion and take on
the characteristics of more typical soft cliff.
It is suggested that in using the Radcliff criteria that the identification of sand dune BAP habitat for
CWS designation takes account of the following physical parameters
• Presence of a transition from embryo dune through semi fixed dune to dune grassland
• The presence of only embryonic dune is not sufficient to warrant assigning a section to sand
dune BAP habitat due to the often ephemeral nature of this habitat.
9 Findings
Table 1 shows those sections that contain BAP habitat and are recommended for further assessment as
CWSs. The total length is 10km with an approximate area of ~32ha. Currently most CWSs and SSSI
boundaries also incorporate the beach down to low tide but the figures below relate to the area of
habitat. For soft cliff the area given is likely to significantly underestimate the actual area of habitat due
to the slope of these sections. Soft cliff habitat covers ~16ha and sand dune covers ~16ha. See Figs 1-3.
Table 2 shows sections of coast surveyed that contain BAP habitat and may be of CWS quality. These
sections generally have significant land use issues affecting their integrity. See Figs 1-3.
Table 3 shows sections of coast surveyed that are not considered to contain BAP habitat (and therefore
are not potential CWS) or where they are of very low quality due to current management, size of
restricted range of features. In some cases these stretches do contain areas of sand dune, in particular,
that contribute toward local biodiversity and which could be subjected to more favourable
management. See Figs 1-3.
6
Table 1 Sections recommended for consideration as CWS
Section
Section name
BAP habitat
Description
reference
1
Hopton – south
Soft cliff
Very open and sparse
grassland community with
bare ground. Some slumping
and surface erosion. Cliff top
improved grassland
3
Hopton north
Soft cliff
Closed sward grassland but
extensively grazed by rabbits
with little bare ground
4
Hopton golf
Soft cliff
Closed sward
course
grassland/scrub on dormant
cliff with little bare ground.
Embryo dune formation and
grassland on cliff top
8
Caister
Sand dune
Embryo to fixed dune
transition despite presence of
sea wall. Scrub and ruderals
in places. Eroding and
depositional frontage
10
California
Soft cliff
Very open and sparse
grassland community with
bare ground. Some slumping
and surface erosion.
11
Scratby
Soft cliff
Dormant cliff with closed
grass sward and scrub and
extensive climbing dune.
Eroding frontage
13
Hemsby north
Sand dune
Extensive fixed dune, dune
grassland contiguous with
and similar vegetation to
adjacent SSSI. Eroding
frontage
14
Cart Gap south
Sand dune
Fore dune established on top
of sea wall, similar to
adjacent CWS.
SMP10 recommendation
Comment
Length
(m)
360
Area
(ha)
0.7
No active intervention
Backed by open ground and
protected by sea wall
610
1.3
Backed by developed land/caravan
site
1270
3.4
Backed by golf course
1120
5.7
Hold the line up to
medium term
Backed by developed land/caravan
site
1570
1.8
Hold the line up to
medium term
1000
3.3
Backed by built development, some
amenity grassland and CWS
comprising bracken dominated
grassland
Backed by built development, some
amenity grassland
720
9.5
from present day
250
0.6
Backed by built development.
Some chalets in dunes
Backed by chalet development
7
Section
reference
17
Section name
BAP habitat
HappisburghOstend
Soft cliff
20
Bacton south
Soft cliff
21
Bacton
Soft cliff
Description
Extensive slumping and
slippage, early successional
stages, a few patches of
Phragmites. Much bare
ground and some stable
sections with closed sward
grassland. Cliff top grassland
Area of rapidly eroding soft
cliff and lichen rich dune
grassland developed on
shallow stable cliff.
Extensive slumping and
slippage, early successional
stages, a few patches of
Phragmites. Much bare
ground and some stable
sections with closed sward
grassland. Extensive area of
lichen rich grassland
developed on shallow stable
cliff.
Length
(m)
2000
Area
(ha)
2.3
420
660
SMP10 recommendation
Comment
from present day
Backed by open ground mainly
grassland
0.9
Hold the line up to
medium term
Backed by built
development/caravan site and part
of Bacton gas terminal.
2.6
Hold the line up to
medium term
Backed by Bacton gas terminal.
Revetments recently improved
causing damage to grassland and
loss of embryo dune.
Similar in character to adjacent
Mundesley cliffs (geological) SSSI
8
Table 2 Sections that could meet CWS criteria but where there are significant land use issues affecting their integrity
Section
Section name
BAP habitat
Description
Length
Area
SMP
reference
(m)
(ha)
recommendations
7
Caister south
Sand dune
Fore dune to dune grassland 720
3.1
with eroding frontage.
12
Hemsby south
Sand dune
Fore dune to dune grassland
with eroding frontage.
850
8.4
Comment
Intense urban pressure on dune
frontage, highly fragmented habitats,
coastal squeeze. Scope for more
sensitive management to develop sand
dune system as a flood defence.
Extensive chalet development in dunes.
Significant areas of dune remain
amongst chalet development. Need to
protect these remnants. Scope for more
sensitive management to develop sand
dune system as a flood defence
Table 3 Sections that do not merit consideration as CWS but may nonetheless contain semi natural habitat
Section
Section name
Habitat
Length
Comment
reference
(m)
2
Hopton
Sand dune-type vegetation
410
Intense urban pressure on dune frontage. Little apparent scope for biodiversity
developed on sea wall
enhancement
5
Gorleston south Soft cliff - dormant
120
Intense urban pressure. High coverage of Ruderal plants and garden debris. Little
apparent scope for biodiversity enhancement
6
Gorleston
Soft cliff - dormant
1420
Stable cliff, amenity grassland and footpaths. Little apparent scope for biodiversity
enhancement
9
Caister north
Sand dune
560
Intense urban pressure. Embryo dune vegetation on accreting beach
15
Cart Gap north
Sand dune
700
Chalet development. Sand dune vegetation developed on sea wall protecting soft
cliff. Little apparent scope for biodiversity enhancement
16
Happisburgh
Soft cliff
1150
Rapidly eroding soft cliff backed by open land. This may however be a temporary
south
phase. Little apparent biodiversity interest due to lack of any vegetation cover and
very high rates of erosion. Little apparent scope for biodiversity enhancement
18
Walcott
None
1100
Seawall with no semi natural habitats apart from beach
19
Walcott north
Sand dune-type vegetation
1950
Intense urban pressure on soft cliff frontage. A narrow strip (up to 10m wide) of
developed on sea wall
dune-type vegetation that can be easily damaged through insensitive development.
Little apparent scope for biodiversity enhancement but could be protected by more
sensitive planning
Gt Yarmouth
Sand dune (embryo)
5000
Intense urban pressure on dune frontage. Scope for more sensitive management to
Haven-North
develop sand dune system as a flood defence
Denes
Not surveyed
9
10 Conclusion
The identification of the above sections as BAP habitat and potentially as CWS will raise the profile of
soft cliff and sand dune BAP habitats away from the currently designated sites. Together they represent
a significant biodiversity resource and form an almost unbroken stretch of habitat. The maintenance
and where necessary restoration and creation of habitat connectivity is a central objective of the
ecological network which identifies the coast as a core area.
The proposals in the current shoreline management plan largely represent a favourable management
outcome for the stretches identified, at least in the medium to long term. The impact of rising sea levels
and increased storms on these habitats are unknown. In addition the potential impacts of coastal
defence works are indicated by the damage caused to the habitats at Bacton which may have been
avoidable if this stretch had been identified as of biodiversity value.
11 Recommendations
•
•
•
•
•
•
•
Agree CWS criteria for sand dune and soft cliff
Further consideration as CWS of sections in table 1 as a priority (this will be dependent on
following the CWS designation procedures)
Further consideration as CWS of sections in table 2 as a lower priority (this will be dependent
on following the CWS designation procedures)
If it is recommended that any stretches in tables 1 and 2 that do not meet the agreed criteria for
CWS should nonetheless be specifically identified as BAP habitats and recorded on any
register of BAP habitats developed by Norfolk Biodiversity Information Service
The Norfolk sand dune and maritime cliff and slope BAP should be amended to incorporate
the results of this survey. The coastal BAP Topic Group will need to assess the level of detail
that this warrants and timing
Survey sections to ascertain their biodiversity interest including invertebrates
That the Environment Agency recognises the sections in tables 1 and 2 as BAP habitats and
treat them as if they are CWSs even if they are not formally designated as such.
10
12 Figures
See relevant MapInfo layers on CD.
Fig 1 Hopton to Gorleston – Coastal BAP habitats
Fig 2 Caister to Hemsby - Coastal BAP habitats
11
Fig 3 Eccles to Bacton - Coastal BAP habitats
12
13 Field survey reports
Target notes for BAP habitat survey
County Boundary to Gorleston
Oct 2007
The stretch of coastline from the Suffolk boundary to Great Yarmouth Harbour entrance consists of
soft sandy cliffs along its entire length. Sea defences are protecting the cliffs from erosion and as a
result they have been almost entirely stabilised. The numbered sections below correspond to stretches
of coastline indicated on the included maps and proceed from south to north.
1. The cliffs at the county boundary are protected by a sea wall. The base of the cliff has been
stabilised by typical yellow dune vegetation, especially Marram Grass (Ammophila arenaria)
which extends about a third to half the way up the cliff face. Towards the cliff top species such
as Red Fescue (Festuca rubra), False Oat-grass (Arrhenatherum eliatus) and Ribwort Plantain
(Plantago lanceolata) become dominant. The cliff top here has a narrow 2-3m band of
vegetation that includes Wild Carrot (Daucus carota), Scarlet Pimpernel (Anagallis arvensis),
Black Knapweed (Centaurea nigra) and Mugwort (Artemesia vulgaris). Beyond this band of
vegetation there is a field of recently sown Festuca grassland containing patches of Common
Centaury (Centaurium erythraea).
2. Between the area of recently sown Festuca grassland and the adjacent pitch and putt course is
an area where the cliff is heavily eroded. The cliff top vegetation around this eroded area has
been left to grow unchecked and contains Chenopodium spp, Common Ragwort (Senecio
jacobea) and Corn Spurrey (Spergula arvensis).
3. From the area of eroded cliff to Beach Road the cliffs drop somewhat in height so that almost
all of the vegetation on the cliff face is typical dune vegetation dominated by Marram Grass
with some Red Fescue, Colt’s-foot (Tussilago farfara) and Ragwort. The cliff top has a golf
course and playing field upon it that are dominated by Perennial Ryegrass (Lolium perenne)
and Clover (Trifolium spp).
4. Beyond the Beach Road entrance is a small stretch of houses whose gardens face onto the cliff
top. There is a narrow 4-5m wide area of well-mown Perennial Ryegrass sward between the
gardens and the cliff edge. The cliffs here have had garden waste such as grass clippings
dumped over the edge resulting in an increased presence of Nettles (Urtica dioca) and
Hogweed (Heracleum sphondylium) in the cliff face vegetation.
5. North of the stretch of houses the cliffs are topped by a static caravan park. Initially there is a
patch of Brambles (Rubus fruticosus) that is then replaced by a Ryegrass sward. The sea wall
ends in this section and is replaced by revetments that are a little further forward from the cliff
face. This extra space has allowed the formation of a narrow band of dunes dominated by
Marram grass with occasional Lyme (Leymus arenarius) grass. Small patches of Brambles
begin to occur in the cliff face vegetation with some Creeping Thistle (Cirsium arvense) and
Nettles. Some patches of the cliff vegetation are clearly rabbit grazed.
6. The caravan park and golf course are separated by a narrow band of Bracken (Pteridium
aquilinum) mixed with some Nettle, Bramble and Gorse (Ulex europaeus).
7. The cliffs have increased in height towards the southern end of the golf course and the
Marram grass now dominates in a band at the cliff base and on the narrow strip of embryo
sand dune. In this area of dune Sea Holly (Eryngium maritimum) and Sea Radish (Raphanus
maritimus) occur occasionally along with non-native Tree Lupin (Lupinus arboreus) that
becomes more abundant towards the north. Brambles begin to dominate some large areas of
the cliff face and elsewhere Cock’s-foot (Dactylis glomerata), False Oat-grass, Yarrow
(Achillea millefolium), Wild Carrot and Common Ragwort make up the majority of the
vegetation with some small patches of Common Toadflax (Linaria vulgaris) and Field
Scabious (Knautia arvensis) occurring. There is a flush in one area dominated by Common
Reed (Phagmites australis). Toward the northern end of this section Ribwort Plantain
becomes more dominant on the cliff face before, as the height of the cliff drops, Marram grass
again dominates the cliff face vegetation. In this area of Marram there is a 20-30m wide area
where the cliff face has been eroded exposing the sandy substrate. Here there are a small
number of what look to be Sand Martin (Riparia riparia) nest holes. On the cliff top there is a
2-8m band of vegetation between the cliff edge and the golf course similar in composition to
that on the cliff face but with some Bracken in places.
8. The revetments are replaced by a sea wall at the foot of the cliffs as the golf course ends and
the houses of Gorleston begin. At the start of this section there is a short stretch of Brambles
13
mixed with Hedge Bindweed (Calystegia sepium) and Honeysuckle (Lonicera periclymenum).
The cliffs for the entire length of Gorleston have been landscaped to form a 45 degree angle
and are covered with a Ryegrass / Clover sward. On the cliff top there is a path and then a long
line of amenity grasslands, putting greens, playgrounds, sports parks etc. At the very end of
the cliffs, Gorse and Bramble have begun to grow amongst the grass sward.
14
Caister-on-Sea to Winterton-Horsey Dunes
Oct 2007
The coastline from Caister to the beginning of the Winterton-Horsey Dunes SAC is made up mostly of
soft sandy cliffs with areas of dunes at the north and south. The majority of this stretch of coastline has
sea defence, either in the form of sea walls or rock armour slowing the level of coastal erosion. The
numbered sections below correspond to stretches of coastline indicated on the included maps and
proceed from south to north.
15
1.
The coast here is fronted by sand dunes dominated by Marram Grass (Ammophila arenaria)
with occasional Common Cat’s Ear (Hypochoeris radicata), Devil’s-bit Scabious (Succisa
pratensis) and Common Ragwort (Senecio jaceobea). The sea wall runs through the middle of
the dunes but has been largely buried. The dunes run back here to the nearby public house.
Further back Common Bird’s-foot Trefoil (Lotus corniculatus) becomes frequent along with
Cock’sfoot (Dactylis glomerata). There is evidence of fires and rubbish dumping in places.
2. The sea wall is less buried along the caravan park here with the dunes built up in front of the
sea wall. The front of the dunes does appear to be eroding. Lyme Grass (Leymus arenarius),
Hoary Ragwort (Senecio erucifolius) and Cock’sfoot occur on the dunes in front of the sea
wall.
3. Past the caravan park the area behind the sea wall is covered by scrub and Bracken (Pteridium
aqualinum). The Bracken occurs along the top of the sea wall with Bramble (Rubus
fruticosus), Sycamore (Acer pseudoplatanus), Ivy (Hedera helix) and Honeysuckle (Lonicera
periclymenum) becoming dominant inland. Toward the north the dunes in front of the sea wall
are becoming narrower and move to behind the sea wall.
4. In front of the sea wall here the dunes occur in a narrow 3-4m wide strip dominated by
Marram with some occasional Lyme grass. On the top of the sea wall there is some Marram
that quickly gives way to Bracken mixed with Bramble. Just before the caravan park Marram
grass becomes more dominant further inland with False Oat-grass (Arrhenatherum eliatus),
Black Knapweed (Centaurea nigra) and Black Horehound (Ballota nigra) occurring towards
the boundary with the school field.
5. In front of the static caravan parks the dunes in front of the sea wall become patchy or
disappear altogether. The dunes occur instead behind the sea wall in a strip dominated by
Marram with a strip of scrub between these dunes and the caravan park. The scrub consists
largely of Bramble with patches of Nettles (Urtica dioica) and Gorse (Ulex europaeus).
6. Dunes begin to appear again in front of the sea wall. The scrubby area behind the sea wall
becomes narrower as an area of Perennial Ryegrass (Lolium perenne) grassland has been
established between the scrub and the caravan park. About halfway up this section the scrub
stops altogether and in front of the sea wall the beach widens significantly where rock reefs
have been constructed before the sea.
7. The wider beach here contains a number of embryo dunes dominated by Marram. The sea wall
turns into a path running through the dunes and between the path and the nearby houses is a
small section of dunes. The dunes here contain Ribbed Melilot (Melilotus officinalis),
Common Bird’s-foot Trefoil, Yarrow (Achillea millefolium) and Mugwort (Atemisia vulgaris).
8. The dunes here are fixed and very narrow, 4-5m wide, Marram only occurs occasionally with
Cock’sfoot and Red Fescue (Festuca rubra) forming much of the grass sward. Ribwort
Plantain (Plantago lanceolata) Ribbed Melilot, Bird’s-foot Trefoil, Creeping Thistle (Cirsium
arvense) and Sea Radish (Raphanus maritimus) occur within the sward.
9. This area is CWS 1443, California Coastal Strip. The dunes to the south here are similar to
that of section 8 but with Marram and some Lyme grass more dominant and Harebell
(Campanula trachelium) occasional. Towards the north of the site the sea wall returns and is
then replaced by rock armour at the cliff base. The cliff face is colonised largely by dune
vegetation with marram growing across to the rock armour sea defences. Hogweed
(Heracleum sphondylium), Colt’s-foot (Tussilago farfara) and Red Clover (Trifolium
pratense) are occasional on the cliff face. There are patches of exposed substrate where the
cliff is eroded and Sand Martin (Riparia riparia) nest holes are present in one area.
10. From California Gap the soft sandy cliffs are protected by rock armour, although some erosion
still appears to be occurring. Marram grass becomes less common as the cliffs move north
with Cock’sfoot, Wild Carrot, Selfheal (Primula vulgaris), Buck’s-horn Plantain (Plantago
coronopus) and Black Knapweed among the cliff face vegetation with a couple of areas of
frequent Field Horsetail (Equisetum arvense). There are a number of places where Sand
Martin nest holes occur in the eroded cliff face. Houses and amenity grasslands top the cliffs
here and there are a number of areas where garden waste has been dumped over the cliff edge.
11. As the rock armour ends dunes appear in front of the cliffs. The dunes are dominated by
Marram with a strip of scrub at the rear that backs onto the base of the cliffs. Sea Buckthorn
(Hippophae rhamnoides) is common among Bramble and occasional Gorse in the scrub. The
cliff face vegetation is much the same as section 10 but with more scrub species such as Sea
Buckthorn and Bramble. Houses and amenity grassland continue to top the cliffs.
12. As the cliffs end the dunes begin to grow in width and height. Marram is dominant with a
great deal of Sea Buckthorn present as well as some bramble in places. The dunes contain a
16
large number of beach huts and holiday homes and towards the northern end of this section car
parks lie at their rear.
13. In this last section before the beginning of the Winterton-Horsey SAC the dunes are
continuing to widen and contain less Sea Buckthorn but more Bramble and some Honeysuckle
(Lonicera periclymenum). A path runs through the back of the dunes from the nearby car park
to the west of which Bracken dominates up to the nearby houses. Along the path the sward is
very short due to trampling and rabbit grazing with some Bryophytes evident in the sward.
17
18
Eccles-On-Sea to Bacton Gas Terminal
Oct 2007
The coast from Eccles to Bacton Gas Terminal consists largely of soft cliffs with occasional areas of
sand dune. Sea defences are present along much of this coastline. The sections numbered below
correspond to the sections of coast indicated on the included maps and proceed from east to west.
1. This area consists of a narrow ridge of fixed sand dune defended on the seaward side by a sea
wall. The dunes are dominated by Marram (Ammophilia arenaria) with some Lyme (Leymus
arenarius), Sand Couch (Elymus farctus) and Cock’s-foot (Dactylis glomerata). Herb species
19
include Common Ragwort (Senecio jacobea), Buck’s-horn Plantain (Plantago coronopus) and
Common Chickweed (Stellaria media) with locally rarer Sea Holly (Eryngium maritimum).
On the landward side the dunes back onto gardens from the nearby properties and there are
some patches of Brambles (Rubus fruticosus agg). The vegetation in CWS 1247 appears to be
largely identical to that in this section.
2. Above the sea wall the dune ridge no longer occurs. The ridge has been reinforced with a
concrete lattice and the gardens of the adjacent houses now run up to the top of this slope
significantly reducing the quality and extent of the habitat. Species present consist largely of
Marram, Buck’s-horn Plantain and Sea Sandwort (Honkenya peploides).
3. The sea wall ends as coast-side properties ceases. Soft cliffs immediately become the
dominant feature here. The sandy cliffs are clearly undergoing continued erosion from the sea
and support little vegetation on their faces with the dominant grasses being Sand Couch
(Elymus farctus) and Yorkshire Fog (Holcus lanatus). Other species present include Buck’shorn Plantain, Scarlet Pimpernel (Anagallis arvensis), Halberd Leaved Orache (Atriplex
hastate), Colt’s-foot (Tussilago farfara) and Common Chickweed (Stellaria media). The cliff
top supports a band of vegetation 8-15m wide that includes Perennial Ryegrass (Lolium
perenne), Yorkshire Fog, Red Clover (Trifolium pratense), Ribwort Plantain (Plantago
lanceolata), Colt’s-foot and Creeping Thistle (Cirsium arvense). Beyond this strip of
vegetation at the cliff edge the land use is arable.
4. The cliffs here increase in height compared with those to the east as well as being somewhat
closer to the sea. This coincides with the appearance of a clay layer at the base of the cliff
below a sandy layer. This clay layer erodes less readily than the sandy layer above and forms a
clay bench on the shore. The cliffs here, because of their closer proximity to the sea, are
undergoing more extreme erosion and have steeper and less vegetated cliff faces than those in
section 3. Sand Martin (Riparia riparia) nest holes are present.
5. At the eastern end of this section where some of the buildings of Happisbugh occur along the
cliff top there is an area of rock armour and the revetments begin again. The beach along this
section contains much rubble from previous cliff collapses and ad hoc efforts at sea defences.
The cliffs here are still steep and fairly sparsely vegetated, obviously undergoing fairly rapid
rates of erosion despite the efforts at sea defence. The cliff top is largely made up of buildings,
gardens or the remains of houses and roads that have collapsed into the sea.
6. Happisburgh Cliffs SSSI.
7. West of the caravan park the cliff top comprises arable fields. From the cliff edge to the field
margin is a strip of cliff top vegetation around 10 –15m wide. The species present are much
the same as for section 6 but with occasional Common Nettle (Urtica dioica). The layer of
clay in the bottom of the cliff face increases in thickness along the previous section and this
continues into this one. The area where the lower clay layer meets the upper sandy layer is
fairly wet as water draining through the pervious sands meets the impervious clays below. The
cliff face vegetation generally occurs above this band in the softer sandy layer above, typically
this vegetation consists of Colt’s-foot, Cock’s-foot, Yorkshire Fog and rarer Hare’s-tail Grass
(Lagurus ovatus) with occasional Plantains (Plantago ssp), Docks (Rumex ssp) and Dandelion
(Taraxacum officianale agg). There are a number of areas along this stretch of cliff where
flushes occur. These flushes are distinct from the generally damp layer along the majority of
the cliffs in that Common Reed (Phragmites australis) occurs, sometimes with Silverweed
(Potentilla anserine), see Plate 6.
8. As the coast moves west towards Walcott the cliffs decrease in height and the clay layer
disappears. The beach here is being built up with material as the revetments along this section
are almost entirely buried by the beach. The cliffs behind are much more densely vegetated.
The vegetation initially consists of similar species to those cliffs east of here with Colt’s-foot,
Cock’sfoot and Buck’s-horn Plantain common. However as the cliffs move west sand dune
species, especially Marram and Sand Couch, become more prominent.
9. From the slipway at Ostend a sea wall replaces the revetments. Houses and gardens front the
top of the sea wall with a small path and bank between these properties and the sea wall. This
path and bank is of poor quality with rubble and garden waste frequent amongst the vegetation
that consists largely of Sand Couch, Marram, Lyme grass, Creeping Thistle and Thrift
(Armeria maritima). At Walcott Gap the road runs adjacent to the sea wall and there is no
vegetation present along this built up stretch of coast.
10. As the sea wall reaches Keswick a path again runs between it and the adjacent properties. Just
before the slipway there is an area where a dune ridge rises up behind the sea wall for a short
distance. The vegetation on the front of this ridge is composed mostly of Marram, Sand
20
Couch, occasional Lyme and Halberd-leaved Orache. On the landward side scrub, largely
Bramble (Rubus fruticosus agg) and Gorse (Ulex europaeus) dominates. Houses reassert
themselves east of the slipway where the ridge is replaced by a narrow path.
11. There is a taller bank here between the sea wall and the adjacent houses where Sea
Wormwood (Artemisia maritima) becomes abundant. This soon gives way to a 6 – 15m wide
dune ridge above the sea wall where houses give way to amenity grasslands on the landward
side. The species here are dominated by Marram and Sand Couch with Lyme, Sea
Wormwood, Buck’s-horn Plantain, Vetch (Vicia sp), Creeping Thistle and Grass-leaved
Orache (Atriplex littoralis) occasional.
12. The narrow dune ridge finishes at Mill Lane where, again, there is a narrow path above the sea
wall and adjacent properties. To the west of the Caravan Park is an area of amenity grassland
at the end of which the sea wall and esplanade are replaced by revetments that are in good
condition. Cliffs rise up at this point but as their bases are bolstered by steel pillings and some
rock armour they are well protected from erosion and thus quite stable and completely
vegetated.
13. The cliffs here gradually increase in height and become a little steeper with exposed substrate
on the cliff face in places. Species on the cliff face include Colt’s-foot, Cock’s-foot, Buck’shorn Plantain and Yorkshire Fog. At the cliff base, especially towards the western end where
the Mundsley Cliffs SSSI begins, Marram and Sand Couch are established and the cliff face
becomes more covered with vegetation showing that this cliff is not experiencing rapid rates
of erosion. At the top of the cliffs here lies Bacton Gas Terminal, the vegetation is similar to
that on the cliff face with Cock’s-foot, Yorkshire Fog and False Oat-grass (Arrhenatherum
eliatus) present with Creeping Thistle and Hogweed.
21
22
23
24
25
14 Photos
Section 1 Hopton south – soft cliff with open sward and climbing dune at base
Section 4 Hopton golf course – stabilised soft cliff with embryo dune
26
Section 8 Caister – embryo dune to fixed dune with scrub at rear
Section 10 California – varied grassland succession with recent landslide
27
Section 11 Scratby – stabilised soft cliff with climbing dune at base
Section 16 Cart Gap to Happisburgh - rapidly eroding soft cliff. Photo taken in October 2007.
Subsequent visit to this site in March 2008 following the storm surge of November 2007 revealed no
vegetation on cliff faces along entire length of this section
28
Section 17 Happisburgh to Ostend – soft cliff with slumping, varied grassland succession and
Phragmites stand
Section 21 Bacton south – showing open, lichen rich grassland on soft cliff and sand dumping resulting
from coast protection works
29
Section 21 Bacton – soft cliff with varied grassland succession, bare ground and recent coast protection
improvements
30

Survey of east Norfolk coast - Norfolk Biodiversity Partnership

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