Coastal Wetlands CR0422 Final Report

DEFRA Developing Tools to Evaluate the Consequences for Biodiversity of Options for Coastal Zone Adaptation to Climate Change (CR0422)

A study modelling the risk of loss from flooding of lowland open-water and wetland priority BAP habitats in the coastal floodplain under a range of sea-level rise scenarios

17 March 2011

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Contents

1. Introduction 1 1.1 Background 1 1.2 Scope of the project 1 1.3 Purpose of this report 3 1.4 What makes this project different? 4 1.5 Project uncertainties 5

2. Priority BAP habitats 7 2.1 Mapping of BAP habitats 7 2.1.1 Data sources 8 2.1.2 Verification of the habitat data 9 2.1.3 Derivation of alternative BAP habitat datasets 10 2.1.4 Distribution of the selected BAP habitats relative to the coastal floodplain 12 2.2 Sensitivity of the selected BAP habitats to saline inundation 13 2.2.1 Effects of saline inundation on BAP habitats 14 2.2.2 Development of sensitivity criteria 15 2.2.3 Sensitivity matrices for BAP habitats 18 2.2.4 Conclusion 22 2.3 Ease of creation of BAP habitats 24 2.3.1 Potential criteria for ranking ease of habitat creation 24 2.3.2 Ranking of ease of habitat creation 27

3. Modelling Approach 31 3.1 Context 31 3.2 General risk assessment concepts 32 3.3 The national flood risk assessment (NaFRA) 34 3.4 Use of the UK climate projections 2009 34 3.5 Assessment of risk to habitats 35 3.5.1 Current risk of habitat loss and further losses in the future 36 3.6 Modelling calculation: worked example 36 3.7 Comparison of outlined methodology with existing approaches 37 3.8 Quality audit 38 3.9 Uncertainty 39

4. Assessment of the area of BAP habitat at risk of loss as a result of coastal flooding 41 4.1 Context 41 4.2 Assessment of areas of BAP habitat at risk of loss 41 4.3 Headline observations 46 4.3.1 Habitats at risk of loss within the coastal floodplain 46 4.3.2 Habitats at risk of loss within designated sites in the coastal floodplain 48 4.3.3 Habitats at risk of loss in Environment Agency regions in the coastal floodplain 49

5. Implications for BAP habitats in England 51 5.1 Projected habitat losses - Overview of Impacts 51 5.2 Legal and conservation policy drivers 52 5.2.1 Implications of the projected losses for European sites 53 5.2.2 Implications of the projected losses for meeting BAP targets 54

6. Conclusions and Suggestions 59 6.1 Conclusions 59 6.2 Suggestions 61

7. References 65

Table 2.1 Comparison of published extents/estimates with nationally mapped habitat extents and project-derived habitat inventories for the selected BAP habitats 12 Table 2.2 Habitat extents in the inventories and percentage in the coastal floodplain 13 Table 2.3 Scale for risk assessment 16 Table 2.4a Reedbed Matrix (habitat only - not accounting for faunal species interest) 23 Table 2.4b Reedbed Matrix (accounting for faunal species interest) 23 Table 2.5b Low-Salinity Saline Lagoon Matrix 23 Table 2.6 Eutrophic Standing Waters (Lakes) Matrix 23 Table 2.7 Ponds Matrix 23 Table 2.8 Coastal and floodplain grazing marsh (ditches) 23 Table 2.9 Grazing Marsh Grass Matrix 23 Table 2.10 Lowland Fen Matrix 23 Table 2.11 Wet Woodland Matrix 23 Table 2.12 Purple Moor Grass and Rush Pasture Matrix 23 Table 2.13 Lowland Raised Bog Matrix 23 Table 2.15 Final ranked list of practical ease of habitat creation 27 Table 3.1 Risk assessment scenarios 35 Table 4.1 Extents of all selected BAP habitats within the coastal floodplain at risk of loss 43 Table 4.2 Extents of all selected BAP habitats within SSSIs in the coastal floodplain at Risk of Loss 44 Table 5.1 Extents of all selected BAP habitats within the coastal floodplain at risk of loss (sample of modelled scenarios) 52 Table 5.4 Estimated costs of replacing habitat at risk of loss 58

Figure 1.1 1 in 1,000 year tidal and tidal/fluvial flood zone 2 After Page 6 Figure 2.1 Comparison of national mapped habitat data (top left) with site habitat map (bottom right) After Page 30 Figure 3.1 The source-pathway-receptor-consequence model of flood risk assessment After Page 40

Figure 3.2 Habitat X at site X After Page 40 Figure 4.1 Area and percentage of selected habitat at risk of loss under 2100 medium with degraded Defences scenario in 1 in 1,000 year tidal and tidal/fluvial flood zone 2 After Page 50 Figure 4.2 Coastal and floodplain grazing marsh extent and areas at risk under scenario 2100 medium with degraded defences in 1 in 1,000 year tidal and tidal/fluvial flood zone 2 in environment agency anglian region After Page 50 Figure 4.3 Lowland raised bog extent and areas at risk under scenario 2100 medium with degraded defences in 1 in 1,000 year tidal and tidal/fluvial flood zone 2 in northern England After Page 50 Figure 4.4 Deciduous woodland extent and areas at risk under scenario 2100 medium with degraded defences in 1 in 1,000 year tidal and tidal/fluvial flood zone 2 in environment agency southern region After Page 50

Appendix A Project Brief Appendix B Project Organisation Appendix C Sources of Mapping Data and GIS Process Undertaken to Derive Lakes and Ponds Datasets Appendix D Details of the Habitat Verification Process Appendix D1 Habitat Verification Data Appendix E Extracts from BAP Priority Habitat Statements Appendix F1 Details of Consultations Undertaken to Inform the Sensitivity Matrices Appendix F2 Summary of Evidence Used to Populate Draft Risk Matrices Appendix G Details of the Workshop Appendix G1 Workshop Materials Circulated in Advance Appendix H Ease of Habitat Creation Scoring Approach and Ranking Analysis Appendix I Summary Evidence and References Supporting the Scoring Decisions Appendix J1 NaFRA Model - Step-by Step Explanation Appendix J2 Modelling Calculation: Worked Example Appendix K Habitat Extents at Risk of Loss Within Each Type of Designated Area and Outside Designated Areas Appendix L Habitat Extents at Risk of Loss Within Environment Agency Regions Appendix M Coastal and Floodplain Grazing Marsh BAP Targets (from BARS)

1. Introduction

1.1 Background

Climate change is widely recognised as one of the major drivers of global biodiversity change and loss, with sea-level rise and increased frequency of extreme events, such as storms and flooding, being among the main agents. Policy responses need to use existing climate projection guidance to anticipate the effects on habitats at the coast, including freshwater, brackish and saline habitats behind the current natural and defended coastline.

Strategies to conserve biodiversity need to be designed and implemented in a timely way so as to facilitate adaptation at the coast and, where constraints on adaptation result in habitat losses, to maximise the opportunities for habitat re-creation inland.

There are several legal and Government policy drivers for the restoration and creation of habitats that are increasingly vulnerable at the coast. For example, there are a number of targets agreed under the UK Biodiversity Action Plan (UK BAP) for habitat restoration and/or creation. These are presented on the Biodiversity Action Reporting System (BARS, http://www.ukbap-reporting.org.uk/) and include, by 2020, the:

• Restoration of 25,000 hectares of relict grazing marsh;

• Initiation of the restoration of 2,800 hectares of former fen;

• Creation of 3,200 hectares of new grazing marsh;

• Creation of 3,000 hectares of reedbed;

• Establishment of 8 new landscape-scale wetland complexes.

Separate to this is the need to replace freshwater, brackish and saline habitat lost at the coast as a consequence of sea-level rise. Delivering the action plans and targets for BAP habitat will require habitat to be created elsewhere to replace that lost at the coast. In addition, there is a statutory requirement under the Habitats Directive to replace habitat where damaging impacts to Natura 2000 sites arise as a result of withdrawal of maintenance of sea-defences or decisions to realign sea defences which are currently protecting such sites.

1.2 Scope of the project

As a result of the predicted effects of climate change and the policy drivers with respect to priority BAP habitats the Department for Environment, Food and Rural Affairs (Defra) has commissioned this project which considers the impacts of climate change on the extent of selected priority BAP habitats behind the natural and defended coastline under a number of climate change scenarios and timeframes (the Defra brief for this project is presented in Appendix A).

Priority BAP habitats selected for inclusion in this project were limited, by constraints on time for the project, to those lowland open-water and wetland priority BAP habitats that can be found in coastal environments:

• Coastal and floodplain grazing marsh;

• Saline lagoons;

• Freshwater open-water habitats (eutrophic standing waters (lakes) and ponds);

• Lowland fens;

• Reedbeds;

• Wet woodland - amended to deciduous woodland for some aspects of the project1;

• Lowland raised bog; and

• Purple moor grass and rush pastures.

Whilst the project scope also requested consideration of the potential effects of sea-level rise on priority BAP species associated with these habitats, it was subsequently decided with the steering group that this task would not add substantially to the project, as it is primarily habitat-focussed. Consideration of priority BAP species was therefore not taken further in the study although an example of the implications for projected losses when faunal species requirements are taken into account is presented.

The study is focussed on England.

This project is one of two similar studies. The other is an Environment Agency-led project, SC060062 - Methods to Assess, Model and Map the Environmental Consequences of Flooding, being undertaken by CEH. The overall aim of the EA-led project was to develop, test and disseminate prototype methods for assessing and mapping the environmental risk, including harmful and beneficial effects, resulting from flooding. It covers saltmarsh habitats and freshwater habitats at risk of fluvial flooding (not tidal and tidal/fluvial which is the focus of this study). There was liaison between the EA project and this Defra project to try to ensure similar approaches were taken wherever

1 The project brief specified that wet woodland be included. However, due to issues with the wet woodland habitat mapping (see Section 2) it proved necessary to find an alternative and a composite deciduous woodland GIS dataset, released by Natural England during the course of the project, was adopted. Although it was not possible to derive the extent of wet woodland from the deciduous woodland dataset, the deciduous woodland dataset was used in the later stages of the study where habitat mapping and analysis of extent of habitat at risk of loss because this was considered to provide the most reliable indication of woodland extent. However where the environmental requirements of BAP habitats are considered it is the requirements of wet woodland that are discussed.

possible. However, the ability of either project to influence the other was limited by the rates of progress of the two projects.

1.3 Purpose of this report

A consultant team led by Entec UK Ltd, working with HR Wallingford and the Centre for Ecology and Hydrology has undertaken this study. The consultant team was overseen by a steering group that provided guidance for the project. The project organisation is presented in Appendix B.

The overall aims of the project were:

1. To achieve a strategic national (England only2) estimate of the extent of selected lowland open-water and wetland priority BAP habitats behind the natural and defended coastline that may be lost over the next 100 years due to the effects of climate change and sea-level rise; and

2. To categorise the feasibility of recreating each type of habitat and the timescale required.

The definition of habitat loss used in this project is ‘irreversible damage to habitat and change in community structure and other features leading to change to another habitat type (i.e. complete loss of the habitat)’.

The project comprised the following main tasks:

1. Mapping of selected BAP habitats;

2. Development of sensitivity criteria for BAP habitats (to saline flood events);

3. Development of a simple categorisation of ease of practical habitat creation, comprising (a) the development of a set of criteria and associated scoring, against which the ease of habitat creation can be ranked; and (b) to undertake the scoring, and report the ranked list;

4. Modelling areas of habitat at risk. This used the Risk Assessment for System Planning (RASP) method as applied within the National Flood Risk Assessment (NaFRA)3 09 analysis to ascertain the probability and depth of flooding to BAP habitats around the coast of England over a number of climate change and coastal management scenarios. The analysis considered the effects of tidal and tidal/fluvial events, but not fluvial events and the modelling boundary was the Environment Agency’s 1:1,000-year tidal and

2 National in this report refers to England

3 The Risk Assessment for System Planning (RASP) approach has previously been used to carry out the National Flood Risk Assessment (NaFRA) for the Environment Agency to help strategic planning of investment in flood risk management at a national scale (see Section 4 for more detail).

tidal/fluvial flood zone 2 extent (hereafter ‘coastal floodplain’ – see Figure 1.1). The results were translated into risk of loss using the criteria derived in task 2 above;

5. Deriving extents and producing maps for habitat areas at risk of loss due to climate change-related effects on sea level;

6. Assessing the extent of habitat replacement needed and associated timescale.

This is the final project report and hence describes tasks 1-6 listed above. The report sections are listed below:

• Section 2 details the tasks undertaken related to the selected priority BAP habitats. Section 2.1 discusses the national habitat inventories, whilst Section 2.2 describes the derivation of sensitivity matrices for habitats and Section 2.3 describes the development of simple categorisation of ease of practical habitat creation;

• Section 3 details the approach taken to the modelling of the areas of habitat at risk and the derivation of those areas;

• Section 4 discusses the areas of habitat at risk and presents a limited number of maps illustrating the model output. Outputs are also presented which identify areas of habitat at risk within designated conservation sites in England and areas of habitat at risk broken down geographically into Environment Agency regions4;

• Section 5 discusses the implications for the selected priority BAP habitats of the projections of habitats at risk of loss under the range of modelled climate change scenarios, set in the context of existing conservation legislation and policy drivers;

• Section 6 presents brief conclusions from the study and makes a number of suggestions for future actions.

1.4 What makes this project different?

A national overview has been derived of potential BAP habitat loss in the coastal floodplain as a result of climate change and an analysis has been undertaken of the ease of habitat creation. There are a number of features of this project that make it different from others:

• This the first time that a probabilistic approach has been taken to assess the potential loss of habitat as a result of climate change. Whilst NaFRA has been used to assess property damages previously, no studies have developed a probabilistic approach to the assessment of potential habitat losses;

4 Although the areas of habitat at risk have been broken down in Environment Agency regions it is acknowledged that the Agency is not responsible for replacing all the habitat losses.

• The project has drawn on national experts, scientific literature and empirical evidence, to inform consistent national assumptions on the sensitivities of lowland open-water and wetland priority BAP habitats behind the natural and defended coastline, to coastal inundation. This means that, for this project, it has not been assumed that exposure to flooding automatically results in habitat loss, but takes account of duration and frequency of flooding. This is a novel approach developed specifically for this project but potentially having wider application;

• A single national-scale model has been used to derive predictions of potential habitat losses in the coastal floodplain at a national scale. This has ensured that the predictions have all been made using the same climate-change assumptions, and losses are predicted for standard and consistent time periods. This contrasts with regional or locally based studies that have not necessarily used the same approaches or time periods;

• The time periods for predictions extend to 2100 which will allow strategic decision-makers to plan for habitat creation requirements and coastal zone adaptation in the long term. This contrasts with shorter-term analyses;

• A method of ranking the practical ease of creation of the selected BAP habitats, and the relative ease/difficulty of doing so, has been developed and used in this project. The results of the ranking and the predictions of habitat losses will allow strategic decision-makers to consider habitat creation requirements in the longer term and the potential difficulties associated with achieving them. This is a novel approach developed for this project.

1.5 Project uncertainties

The project the team has encountered numerous areas of uncertainty including:

• The spatial distribution and extent of lowland open-water and wetland priority BAP habitats that can be found in coastal environments of England i.e. there is significant uncertainty associated with the available national mapping of BAP habitats;

• The sensitivity of these BAP habitats to inundation from the sea;

• The effects of climate change on sea levels in the future;

• The difficulty in predicting how, where and how often flood events may take place, and the consequences of these events for flood extent and related habitat loss;

• The feasibility of re-creating BAP habitats that effectively replicate those lost.

Awareness of these uncertainties and knowledge gaps has allowed the project team to address, or at least acknowledge them throughout. Within the restraints of budget and timetable, the project has used the best nationally applicable tools available, drawn on expert knowledge and made a number of important assumptions to reduce uncertainty. Where uncertainties and data gaps remain, these are described in the report. Notwithstanding uncertainties and knowledge gaps, the project does provide an important first indication of the extent of BAP habitat that may be lost in the coastal floodplain as a result of climate change and the potential

difficulties of replacement. Consequently, it will allow strategic decision-makers to better ensure the conservation of the natural environment for future generations.

100000 200000 300000 400000 500000 600000 700000 700000

N 600000 600000 500000 500000 400000 400000 300000 300000 200000 200000 100000 100000 0 0

100000 200000 300000 400000 500000 600000 Key Coastal Zone Adaptation Extent of 1 in 1,000 year tidal and to Climate Change tidal/fluvial flood zone 2 (Coastal Floodplain)

Figure 1.1 1 in 1,000 year tidal and tidal/fluvial flood zone 2 The study covers selected fresh water wetland and open water BAP habitats in the 1 in 1,000 year tidal and tidal/fluvial flood zone 2. 0 100 G:\MODEL\PROJECTS\EA-210\24903 Coastal Biodiversity and Climate Km March 2011 Change\ArcGIS\Figures\24903-S01d_Floodzone2.mxd Scale: 1:3,500,000 @ A4 24903-S01d stokr

Based upon the Ordnance Survey Map with the permission of the Controller of Her Majesty's Stationery Office. © Crown Copyright. AL100001776

2. Priority BAP habitats

This section describes:

• The mapping of BAP habitats for the project (Section 2.1);

• The development of criteria to describe numerically the sensitivity of the BAP habitats to saline inundation that could be used in the NaFRA modelling (Section 2.2);

• The development of a simple categorisation of ease of practical habitat creation (Section 2.3).

2.1 Mapping of BAP habitats

To allow an analysis of the extent of the target priority BAP habitats in England at risk of loss due to coastal flooding, maps of the extents of the selected priority BAP habitats were required. The aim of this task was therefore to produce maps of the selected priority BAP habitats, located inland of the current natural and defended coastline, within the coastal floodplain (see Figure 2.1) which is the extent of the NaFRA model being used for this project, that could be used in the modelling process and assessment of projected habitat losses under a range of climate change scenarios. The process undertaken in producing mapped habitats for use in the study comprised the:

• Identification of sources of mapping data;

• Verification of the mapped data;

• Derivation of useable mapping data (eliminating habitat overlaps).

The selected habitats were:

• Coastal and floodplain grazing marsh;

• Saline lagoons;

• Freshwater open-water habitats (eutrophic standing waters (lakes) and ponds);

• Lowland fens;

• Reedbeds;

• Wet woodland - amended to deciduous woodland for some aspects of the project5 (Woods);

• Lowland raised bog;

• Purple moor grass and rush pastures.

The locations of these habitats relative to designated sites are also important for this project (i.e. extent found within and outwith particular designated sites: Site of Special Scientific Interest (SSSI); Special Area of Conservation (SAC); Special Protection Area (SPA); and Ramsar site.

2.1.1 Data sources

National habitat and site boundary data

GIS data indicating designated site boundaries (SSSI, SAC, SPA and Ramsar) were obtained from Natural England (see Appendix C). The steering group also requested that the team consider County Wildlife Sites. However no nationally-based mapping of these sites could be located and these are therefore not considered further in this study. The distribution of the selected priority BAP habitats were obtained from Natural England (see Appendix C). However, there was no available GIS representation of eutrophic standing waters (lakes) or ponds. It was therefore necessary to derive datasets for lakes and ponds. The final eutrophic standing waters (lakes) inventory contained 3,051 waterbodies whilst the ponds inventory contained approximately 388,000 ponds. The process undertaken to derive these habitat inventories is described in Appendix C.

Regional habitat data

At the time of writing Natural England was undertaking a programme of reviewing and updating the BAP datasets on a region/county by region/county basis. This task was undertaken at a local level on a contract basis. Updated regional datasets were obtained, where available and complete (see Appendix C).

It should be noted that although these updated data were obtained, they had not been audited by Natural England6 and Entec was therefore advised not to incorporate these within the habitat mapping to be used for the assessment

5 The project brief specified that wet woodland be included. However, due to issues with the wet woodland habitat mapping it proved necessary to find an alternative and a composite deciduous woodland GIS dataset, released by Natural England during the course of the project, was adopted. Although it was not possible to derive the extent of wet woodland from the deciduous woodland dataset, the deciduous woodland dataset was used in the later stages of the study where habitat mapping and analysis of extent of habitat at risk of loss because this was considered to provide the most reliable indication of woodland extent. However where the environmental requirements of BAP habitats are considered it is the requirements of wet woodland that are discussed.

of potential habitat losses described in Sections 3 and 47. However, a brief comparison was made between the national dataset and the regional dataset for Norfolk to provide an indication of how different the updated regional datasets might be compared to the national data (see Section 2.1.2. and Appendix D). Additionally, these regional data were used within the habitat verification process that is described in Section 2.1.2.

Entec was not made aware of any other updated datasets.

2.1.2 Verification of the habitat data

The BAP habitat data available from Natural England were compiled from a series of other datasets, some of which were old and hence highly likely to now be unreliable. For example, the primary source of data on the extent of Coastal and Floodplain Grazing Marsh is ‘The Distribution of Lowland Wet Grassland in England (1976)’; whilst for reedbeds the key source is ‘The Inventory of British Reedbeds (1993)’. Additionally, there is known to be some overlap in the data, albeit that some habitat overlap is allowed within the criteria for mapping that Natural England employs, and there is a considerable amount of uncertainty in the mapping of the available data.

Two methods of habitat verification were used during this project:

• Review of the nationally mapped data attributes;

• Comparison of the national data with data derived from more recent site surveys, regional data, and also the existing knowledge of habitats present on sites held by the reviewers (Andy Brooks, Graham Morgan and Owen Mountford).

Details of these analyses are presented in Appendix D but they indicated that there was:

• Habitat mis-mapping and over-estimation of the habitat extents in the national datasets. As an example Figure 2.1 illustrates the distribution of reedbed at Holme on the north Norfolk coast taken from a habitat map produced by the Environment Agency and compares this to the distribution of reedbed suggested by the national BAP datasets. A clear over-estimation of the extent of reedbed is evident in the national dataset. However, the close match between saline lagoon distribution on the Environment Agency habitat map and in the national dataset is also worthy of note, illustrating that data issues are not consistent across habitats. The habitat mis-mapping and over-estimation is believed to be caused, at least partly, by the inclusion often of the same botanical communities in the definitions of more than one priority BAP habitat (see Appendix D and E);

6 These were datasets available at the time the habitat mapping element of this project was undertaken. These datasets may now have been audited by Natural England and/or new regional datasets may now have become available. However, they have not been gathered for this project.

7 At the time of publication the revised regional inventories are about to be incorporated into the national datasets by Natural England.

• Relatively low agreement between national and site specific data;

• Data overlaps leading to potential for double counting of areas and also the extensive mis-mapping of habitats remaining within the regional datasets.

A consequence of the degree of uncertainty and over-estimation of the habitat extents in the available mapped data was that the modelling of the extents of habitat at risk from sea-level rise may over-estimate the potential habitat losses. The potential for this to occur was reduced by the derivation of alternative BAP datasets.

2.1.3 Derivation of alternative BAP habitat datasets

The results of the habitat verification process described in Section 2.1.2 indicated that it was not possible to use either the original national or regional datasets as representations of the distribution of BAP habitats for predicting the extents of habitat at risk during the modelling process (see Section 3 and 4). Potential alternative sources of habitat inventory data were therefore investigated. Other datasets variously used by the Wetland Vision project or by Natural England were also checked but the available data were all deemed unsuitable, primarily because these comprised aggregated datasets that had not retained the habitat attributes and hence it was not possible to define geographic extents for each of the habitat types of interest. Progressing with aggregated wetland datasets was rejected because this would have meant assigning to wetlands a single, generalised, sensitivity to coastal inundation. It was considered that this would have devalued the work that contributed to the development of sensitivity matrices (see Section 2.2) and modelling analysis (see Section 3 and 4).

It was decided that the best option was to derive project-specific habitat inventory datasets. The primary requirement was for datasets with no overlaps between the different habitat layers. The approach taken was to use the habitat inventories in an order that reflected the project team and steering group’s confidence in the data. The listing is presented below:

1) Saline lagoons (most confident);

2) Ponds and eutrophic standing waters (lakes);

3) Deciduous woodland (replacing the wet woodland dataset for mapping purposes – see below);

4) Lowland raised bog;

5) Coastal and floodplain grazing marsh;

6) SSSI unit information;

7) Purple moor grass and rush pasture;

8) Reedbeds;

9) Lowland fens (least confident).

There was greatest confidence in the saline lagoons ponds and eutrophic lakes. The ponds and eutrophic lakes datasets were prepared for this project from maps. In order of reducing confidence, next came deciduous woodland, which is a recently-derived national inventory. The reason for using the deciduous woodland dataset is that during the project the inventory for wet woodland, which was considered by the Natural England and the project team to be very poor in any case, was withdrawn by Natural England and replaced with a composite deciduous woodland BAP inventory, from which it was not possible to specifically identify wet woodlands. That said, the composite deciduous woodland BAP dataset has been derived by Natural England primarily from relatively recent mapping and aerial photographic sources, in which there was a relatively high degree of confidence. The steering group then advised that there was a reasonable degree of confidence in the lowland raised bog and the coastal and floodplain grazing marsh datasets. There was least confidence in the purple moor grass and rush pasture, reedbeds and fens data. However, in light of the issues with these datasets identified during the habitat verification process it was considered that an additional dataset should be introduced: SSSI Unit Information. Although known to be imperfect, there was more confidence in the SSSI Unit information than in the purple moor grass and rush pasture, reedbeds and fens data.

The national Natural England habitat inventories and the project-specific derived ponds and lakes data were first aggregated in GIS to remove any overlaps or duplicate polygons. Once these datasets had been organised, they were then combined together beginning with the dataset in which there was least confidence, each time overwriting the less reliable dataset with the more reliable.

The final, combined, dataset was then checked to remove any remaining geographical overlaps and then disassembled used to produce a single layer for each habitat requiring assessment in the study.

Table 2.1 presents a comparison of the UK BAP published extents of priority BAP habitats, the extent presented by the habitat inventories for England used in the habitat verification process and the extents derived from the overwriting process.

Table 2.1 Comparison of published extents/estimates with nationally mapped habitat extents and project-derived habitat inventories for the selected BAP habitats

Habitat UK BAP Published extent NE Inventory extent for Project-derived inventory (ha)/ estimate/No. England (ha)/No. extent (ha)

Coastal and floodplain grazing UK ca 300,000 ha, England 229,762 ha 15,8871 ha marsh 200,000 ha

Saline lagoons Not stated 1,479 ha 1,336 ha

Eutrophic standing waters (lakes) England estimate 54,000 ha, 22,287 ha, 3,051 matching 21,685 ha 3,919 lakes1 polygons

Ponds No area quoted/80,000 outside 25,589 ha/388,197 ponds 25,589 ha/388,197 ponds curtilage (gardens) nationally, 77,639 priority ponds nationally assuming 20% of the total

Lowland fens 3,000 ha in Broadland. No 117,991 ha 16,482 ha national figure given

Reedbeds UK 5,000 ha 66,365 ha 4,830 ha

Wet woodland UK 50-70,000 ha (crude 158,437 ha 528,2912ha estimate)

Lowland raised bog Ca 500 ha 9,964 ha 9,450 ha

Purple moor grass and rush UK ca 56,000 ha, England 22,057 ha 8,933 ha pastures ca 5,281 ha

1 Note that the estimated extent of eutrophic standing waters (lakes) comes from the UK BAP Priority Habitat Description whilst 3,919 is the number of waterbodies included in the Environment Agency sourced data. 2 The extent derived comprises all deciduous woodland BAP habitats, not just wet woodland – hence the significant increase.

It is apparent from Table 2.1 that the project-derived habitat inventory data are much closer, in terms of extent (ha), to the UK BAP estimates of the selected BAP habitat resource than the Natural England inventory extents for England available from www.gis.naturalengland.org.uk. It should be noted that there are certain to be inaccuracies in the precise distribution of the habitats in the derived alternative habitat datasets and, like the Natural England habitat inventories, the derived data probably underestimate the amount of BAP habitat outside designated areas. However, it was considered that the project had derived the best currently-available national overview of the distribution of lowland open-water and wetland priority BAP habitats. These derived habitat data were taken forward for use in the modelling of risk of habitat loss described in Sections 4 and 5 of this report.

2.1.4 Distribution of the selected BAP habitats relative to the coastal floodplain

The priority BAP habitats that are included in this project are not distributed evenly across the country. Table 2.2 indicates, on the basis of the derived alternative BAP habitat inventories, the habitat extents included in the inventories and the percentage of overall resource of each habitat situated in the coastal floodplain (see Figure 1.1).

Table 2.2 Habitat extents in the inventories and percentage in the coastal floodplain

Habitat National (England) Extent in coastal floodplain of Percentage of extent (ha in England (ha in alternative derived BAP habitat in alternative derived inventory) England in inventory) coastal floodplain

Saline lagoons 1,337 1,112 83.2%

Coastal and floodplain grazing marsh 158,872 91,230 57.4%

Reedbed 4,831 2,564 53.1%

Lowland raised bog 9,450 2,898 30.7%

Lowland fens 16,482 1,964 11.9%

Ponds 25,590 1,889 7.4%

Eutrophic standing waters (lakes) 21,686 1,511 7.0%

Deciduous wood 528,292 5,768 1.1%

Purple moor grass and rush pasture 8,933 85 1.0%

Totals 775,472 109,020

Over half of the English resource of coastal and floodplain grazing marsh, reedbed and, not surprisingly, saline lagoons in the derived alternative habitat inventories are situated in the coastal floodplain. This illustrates the importance of this coastal zone in maintaining the national resource of these habitats. It is also worthy of note that the composition of BAP habitat in coastal areas will be influenced by the coastal environment and hence will often be different from those located in more inland locations. As a result this is considered to add conservation value to these habitats, thus reinforcing the importance of the coastal zone in supporting these priority BAP habitat types.

2.2 Sensitivity of the selected BAP habitats to saline inundation

To facilitate assessment of the effects of climate change scenarios on lowland open-water and wetland BAP habitats it was important to understand the sensitivities of the BAP habitats to saline inundation and to be able to translate the habitat sensitivities to inundation into a set of rules that could be used in the NaFRA modelling. This required the development of a method to represent the sensitivities of the habitats numerically.

The aim of this task was therefore to derive a numerical representation of the sensitivities of the habitats to saline inundation that could be used in the modelling process and assessment of projected habitat losses under a range of climate change scenarios. The process undertaken in the development of a method to represent the sensitivities of the habitats numerically comprised:

• Literature review which yielded limited information (Section 2.2.1);

• Development of sensitivity matrices, drawing on the knowledge of experts, that describe the sensitivities of the selected BAP habitats to saline inundation.

2.2.1 Effects of saline inundation on BAP habitats

All of the selected open-water and lowland wetland BAP habitats can be found behind the natural and defended coastline and, apart from saline lagoons, have a predominantly freshwater character. Inundation of these habitats with brackish/saline waters has the potential to result in damage or loss through mechanisms such as:

• Changes in sward species composition (loss of salt intolerant species and/or increase in salt tolerant species e.g. ref Broads fens report);

• Impacts on growth through alteration of the soil-water potential;

• Changes in soil structure (either the flocculation of clay minerals or dispersion of particles);

• Changes in fauna (e.g. loss of invertebrate populations);

• Loss of amphibians and fish that may be important for carnivorous birds such as bittern.

The magnitude of the effect on the habitats depends on a range of parameters including:

• Salinity level of the water flooding a habitat;

• Pre-existing salinity level of the habitat being affected, e.g. saline ditches or fresh water ditches;

• Frequency of flooding;

• Duration of flood events;

• Season the event occurs in;

• Presence and degree of freshwater flushing to which a particular habitat is exposed.

Additionally, the effects of inundation are not the same for each habitat as different species and communities will react differently to different levels of salinity.

Published studies on salinity tolerances of species and communities were largely qualitative in approach. They did not provide analysis of a range of salinity exposure scenarios, tending instead to describe general tolerances to certain levels of salinity, if indeed the subject was covered at all. The published information consulted included examination of Ellenberg values, laboratory-based exposure experiments and the Agency’s Ecohydrological Guidelines for Lowland Wetland Plant Communities (Wheeler et al., 2004). Similar guidance on the requirements of reedbeds, saline lagoons, lowland wet grassland and wet woodland were also consulted.

The qualitative and incomplete published information available on the effects of saline inundation on BAP habitats posed a problem for the project because of the need to define a set of numerical rules- to describe the relationship between saline inundation and consequent effects on the habitats - that could be used in NaFRA.

2.2.2 Development of sensitivity criteria

The parameters used by the NaFRA model determined the development of the format of the rules. Although it is acknowledged that the magnitude of the effect on the habitats depends on a range of parameters the NaFRA modelling can only represent flood frequency and depth, which is translated to flood duration. Therefore, the approach adopted was to develop a series of sensitivity matrices that describe the risk to the BAP habitats of exposure to a range of inundation events in terms of flood frequency and flood duration (see Section 3 for further information on how flood frequency and flood duration were modelled).

To complete a matrix for each BAP habitat an assessment was required of the likelihood of habitat loss for each cell of the matrix8. There are several possible definitions of ‘loss’, including:

• Significant change in vegetation composition;

• Loss of ecological functionality;

• Complete change in habitat type/complete loss.

In this study the definition of loss used was ‘irreversible damage to habitat and change in community structure and other features leading to change to another habitat type (i.e. complete loss of the habitat)’ To express the likelihood of loss, a scale of likelihood of loss was required to complete the matrices. The scale adopted is indicated in Table 2.3.

8 For coastal and floodplain grazing marsh two matrices were derived, one for the grazing marsh ditches and one for the grassland, as it was expected that these two interest features would be affected differently.

Table 2.3 Scale for risk assessment

Value Assigned Risk

1.0 Absolutely certain the habitat will be lost

0.9

0.8 Very likely that the habitat will be lost

0.7

0.6

0.5 Equally likely that the habitat will be lost or will recover

0.4

0.3

0.2 Very unlikely that the habitat will be lost

0.1

0.0 Absolutely certain the habitat will recover

It was not proposed that the project would seek to predict what the habitat would change to even though new BAP habitat might be created where another was lost, for example, saltmarsh replacing grazing marsh.

The NaFRA flood risk model has limitations in how it can represent the environment. A few key assumptions therefore had to be made when completing the sensitivity matrices:

• Flushing with freshwater is a key feature supporting habitats on many sites in coastal areas and will significantly influence the impacts of any inundation with brackish/saline water. The NaFRA model cannot predict the presence and effects of flushing with freshwater. However, it is considered that the matrices derived implicitly consider the effects of flushing because they as far as possible they are based on observations from sites that experience flushing;

• Salinity gradients exist across many freshwater sites in coastal environments and they affect how a habitat reacts to inundation with brackish/salt water. The assumption made when completing the matrices was that, with the exception of saline lagoons, the habitats were freshwater, not brackish. This provided a conservative (worst-case) indication of effects when the modelling was undertaken;

• There are variations in the salinity of water that inundates sites, depending on the location of the site relative to the coast. For the purposes of the analysis, it was assumed that the inundation was with undiluted sea water;

• There may be regional or national variations in the sensitivity of the same BAP habitat. Since this project was aiming to give a broad overview at a national scale, the intention was to use only one sensitivity matrix for each habitat (with the exception noted above of grazing marsh). The assumption was that this would give a national average view of the sensitivity to saline inundation;

• The effects of inundation may vary with season. The NaFRA modelling does not currently include seasonality as a parameter so the assumption made was that a saline flood event could happen at any time of year and that the effects would be the same whenever a flood occurred;

• Effects of rising sea level resulting in backing up of freshwater and increasing freshwater flooding are not considered.

The approach to completing the matrices was to undertake an initial, extensive round of consultation with site managers and other habitat experts from a wide range of organisations. This was then complemented by a desk study of relevant literature, and finally a draft set of matrices was produced. A workshop was then held at which the draft matrices were discussed and revised by a number of invited experts. Further information on the consultations and workshop are presented in Appendices F and G respectively.

Following the workshop, the project team undertook a review of all of the matrices to ensure that there were no anomalies between the matrices, which could have been introduced because they were derived by four different break-out groups simultaneously. Minor amendments were needed, primarily to the reedbed matrix, as this had been deemed by the reedbed break-out group to be more sensitive to saline inundation events than the matrix derived for lowland fens, and also to the grazing marsh grass matrix, which was made less sensitive to short duration saline events. Following the workshop, Jeremy Biggs of Pond Conservation was consulted to provide advice on completion of a ponds matrix.

One matrix was derived for each of lowland raised bog, ponds, eutrophic standing waters (lakes), lowland fens, purple moor grass and rush pasture and woodland, whilst two were derived for each of saline lagoons, reedbeds and coastal and floodplain grazing marsh. With respect to saline lagoons, workshop participants felt that there were main types of lagoon (low salinity and high salinity) and as a result two matrices were appropriate although it was agreed that only the high salinity matrix should be used in the assessment as the majority of saline lagoons nationally are of the high salinity type. Coastal and floodplain grazing marsh comprises two habitats (grassland and ditches) and it was considered that a different sensitivity matrix was required for each of these. Following much discussion at the workshop two reedbed matrices were produced, one for the reedbed habitat only and one accounting for the sensitivity of the fauna that often inhabit reedbeds, such as bittern. In addition to recording the differences that including species interests can make, the inclusion of both in the modeling process acted as a sensitivity check on the modeling process i.e. a direct comparison was possible between the effects of two matrices on the same habitat.

Some of the key assumptions that applied to the derivation of matrices for all the habitats are:

• Assumptions about the definition of ‘complete habitat loss’. There was much discussion on this point early on in the workshop. The project team indicated that, as the project was being undertaken at a BAP habitat level, the sensitivities indicated by the matrices should reflect those for the habitats themselves and not the associated fauna that may make use of them. This resulted in significant discussion on reedbeds, where much of the perceived conservation interest relates to the species supported by the reedbed. Nonetheless, the habitat basis for the matrices was in general the key assumption adopted in the break-out groups with the threshold being defined as point at which

‘irreversible damage to habitat and change in community structure and other features occurred leading to change to another habitat type (i.e. complete loss of the habitat)’;

• Assumptions about inundation. It was indicated by the project team that, in order to derive the sensitivities indicated by the matrices, it should be assumed that a habitat was completely inundated for the periods and frequencies indicated in the matrices;

• An acknowledgement that there is relatively little empirical evidence of the effects of saline inundation on these BAP habitats. However, the project team felt that there was a good cross-section of experts in the workshop and that, although the sensitivities to saline inundation are uncertain, the experts should, and indeed did, trust their judgement in completing the matrices.

2.2.3 Sensitivity matrices for BAP habitats

The final derived matrices are presented together on one page to allow comparison between them and the key assumptions and comments made about each are presented below.

Reedbed

The initial matrix derived was based upon anecdotal evidence from Cley-Salthouse (North Norfolk Coast) and the consideration of substrate salinity levels from Strumpshaw Common. There was much debate about the definition of loss for reedbeds, as much of the designated conservation interest of the habitat resides in the faunal species that it supports. The group working on reedbeds did ultimately follow the guidance of the project team and applied the assumption that a reedbed is lost when the reed dies and does not grow back.

It was also observed that freshwater and tidal reedbeds are ecologically different. Tidal reedbeds are excluded from the matrix as they represent uncommon variants that are less sensitive than freshwater reedbeds. There was an acknowledgement within the group that associated floral and faunal assemblages will change as a result of inundation, but the assumption was that at least some conservation interest would be retained by the recovering reedbed. It was also accepted that reedbed can be valuable in the absence of bittern. A further assumption was that, for any event, freshwater would flush out salinity almost straight away, although contradictory evidence from Strumpshaw Fen (Broadland) indicates salinity in the substrate can linger for two months. As a result of these assumptions, there was considerable disagreement within the group on how the sensitivity of reedbeds should be presented in the matrix.

The matrix that was derived at the workshop presented reedbed as being more sensitive to saline inundation events than lowland fens. However, the project team believes that lowland fens should be viewed as the more sensitive, and felt that this was an anomaly resulting from the workshop groups working separately and without the benefit of being able to ‘calibrate’ the matrices by comparison with each other. After the workshop a compromise was adopted and the matrix for this habitat, presented in Table 2.4a, is the same as that for the lowland fens (see Table 2.10).

However, because of the strong views expressed about reedbeds and their value in supporting other species, a second matrix was defined for reedbed that takes account of the faunal species’ sensitivities and information on the lag time taken to flush salt from reedbeds. This matrix was discussed with the RSPB who agreed it addressed the concerns expressed at the workshop. The additional matrix is presented in Table 2.4b and, for this habitat only; this second matrix was also assessed through the modelling to see what difference is made to the risk of loss of reedbed habitat. The use of the second matrix for reedbed also acts as a sensitivity check on the modelling process and derived projects of habitat losses described in Section 4.

Saline lagoons

Workshop participants felt that it was appropriate to have two matrices for saline lagoons because there are two main saline lagoon types supporting different communities. One type has salinity levels in the 30-40 g/l range (Table 2.5a) and the other has salinity levels in the <10 g/l range (Table 2.5b). The matrices indicate that the two lagoon types have significantly different sensitivities to saline events. However, the participants also indicated that the higher-salinity version is by far the most common and that therefore it was this version that should be used in the modelling.

Eutrophic standing waters (lakes), ponds and grazing marsh ditches

The matrices derived for these three habitats are presented in Tables 2.6, 2.7 and 2.8. The ponds and freshwater grazing marsh ditch matrices are similar, which is logical as they are both essentially small, shallow standing waters.

There was considerable discussion around the issue that fresh grazing marsh ditches will be affected quite differently from brackish ditches. However, the group agreed that it was currently not possible to define the distribution of the different ditches and that they would therefore produce a matrix reflecting the sensitivity of freshwater ditches to saline inundation events for use in the modelling work, as this was the most conservative approach9. In deriving this matrix, it was also observed that there is very little published information on habitat studies following flooding. One notable exception is a paper titled ‘Past History of Sea Flooding and Cause of the 1938 Flood’ by J E Sainty (1939), which reported on species’ return 18 months after inundation of three months. Comments made in this study informed the production of the grazing marsh ditch matrix.

The eutrophic standing water (lake) matrix suggests a different pattern of sensitivity to saline inundation, in that the lakes have been defined as being less sensitive to inundation events than ponds and grazing marsh ditches. This appears logical as the definition of this habitat includes waterbodies that are generally larger than 2 ha (ponds are less than 2 ha), and normally in the lowlands with significant inflows and outflows (the most frequent scenario in the context of this study, although it was noted during discussions that some lakes do exist, especially in the

9 Following completion of the Buglife surveys referred to earlier refinement may be possible for this matrix in the future.

uplands, without inflows and outflows). As a result, it was assumed that the lakes have flushing inputs, meaning that saline water may be flushed relatively quickly from a lake, hastening recovery. Additionally, with inflows and outflows, lakes may have a ready species pool for re-colonisation. Other lake-specific issues that were discussed included the difficulty of defining how the duration of a flood will affect a lake as it depends very much on volume of water in the lake and the relative volume introduced during flooding. Ultimately, the best judgement of the participants was used to define a sensitivity matrix for a general lake situation.

Coastal and floodplain grazing marsh (Grass)

The matrix presented in Table 2.9 was based on information available for Cley-Salthouse (North Norfolk Coast) and Tinkers Marsh (part of the Minsmere-Walberswick site) in East Anglia and was based on effects on the habitat without considering potential effects on supporting species (e.g. wader use).

It was observed that it is difficult to split saltmarsh from grazing marsh as the habitat present on many sites is often in transition between the two and this mosaic/ transition is an interest feature. However, the matrix reflects the more conservative judgement of how freshwater grazing marsh grassland would react as this is more sensitive to saline flooding, although often of low inherent interest.

Lowland fen

It proved difficult to produce a matrix for lowland fen because of the very wide variety of plant communities that are considered to represent the habitat, including a range of mire, swamp and woodland communities (see Appendix G). This wide range includes not only examples of mires that are highly dependent on base-poor groundwater supply and which would be very seriously affected by small inundation events, but also swamp communities that are relatively tolerant of inundation over a much longer period. It was felt that the majority of the sensitive mire communities would be located outside the floodplain and most lowland floodplain fen affected would be comprised of the swamp communities. The matrix was therefore based on knowledge of species-rich fen communities such as the S24 Phragmites australis-Peucedanum palustre tall herb fen and S25 Phragmites australis-Eupatorium cannabinum tall herb fen NVC communities. The mire communities were excluded. It was agreed that, if a matrix for these mire communities was required, they would be adequately covered by the lowland raised bog matrix, which is also comprised of sensitive mire communities (albeit these are generally not the same as those included in the lowland fen BAP habitat).

Information presented in Appendix F was used to define the matrix initially, and it was amended slightly during the workshop break-out group. The final matrix is presented in Table 2.10.

Wet woodland

There was no wet woodland specialist at the workshop. The participants discussing this habitat felt that the wet woodland habitat is most often of interest for its understorey of fen species and the invertebrates that it supports (although the requirements of invertebrates were not accounted for in the matrix). Indeed, all but one of the NVC

communities considered to represent the wet woodland habitat is also included in the definition of lowland fen (see Appendix C). Based on the available data, it was considered by the participants that the tree species would not alter the sensitivity of the BAP habitat compared to lowland fens and therefore the lowland fen matrix was adopted to also represent wet woodland (Table 2.11).

After the workshop it was found that the wet woodland habitat inventory had been withdrawn and replaced by a composite deciduous woodland BAP inventory. The team and steering group therefore decided to include the deciduous woodland inventory in the habitat analysis and investigate which of the sensitivity matrices it would be appropriate to use, recognizing that dry woodland habitats would also now need be considered, in addition to wet woodland. Keith Kirby, Natural England Principal Woodland Specialist, was consulted and his expert opinion was that the purple moor grass and rush pasture matrix should be applied to the woodland inventory in the modeling analysis.

Purple moor grass and rush pasture

This was another difficult matrix to define because, although relatively few NVC communities are considered to fall within the BAP habitat type, they range from fen to rough grassland types. Additionally, there appears to be little or no published information on the effects of inundation and no detailed information obtained during consultations undertaken prior to the workshop10. The group therefore adopted the view, based on professional judgment, that this habitat type is of slightly greater sensitivity than the communities considered for the lowland fen habitat. All the communities included within this BAP habitat type would also have been included in the fen habitat, if mire communities had not been excluded and that at least two of the communities are species-rich communities found in groundwater-fed fens, which are likely to be moderately sensitive to inundation. Hence, it seemed logical that the purple moor grass and rush pasture BAP habitat should be represented as more sensitive than the fen habitat. The matrix is present in Table 2.12.

Lowland raised bog

There is very little available data from which to draw together a matrix for lowland raised bog. From available data it was considered that the vegetation of raised bog (NVC communities M16, M18, M20) is lost after relatively brief inundation by saline water and requires prolonged periods of waterlogging in freshwater and high rainfall in order to re-develop. The group therefore considered that the habitat would be very sensitive to inundation events (perhaps the most sensitive of all the habitats), particularly if the assumption is made that a habitat is completely inundated during any given event. The matrix in Table 2.13 was therefore produced, based on the limited information available (see Appendix F) and professional judgment.

10 Defra has recently sought to increase the knowledge base for this habitat by commissioning new research on the ecological requirements, management and restoration possibilities for purple moor grass and rush pasture.

2.2.4 Conclusion

A number of important issues were raised during the discussions, with the paucity of available data on the effects of saline inundation on these habitats being a recurring theme throughout. Notwithstanding the uncertainties, the experts readily engaged in the process of defining the sensitivity matrices and the resulting matrices reflect a combination of available scientific data, empirical observations and the best professional judgment of the workshop participants. This consultation process has derived the best available representation of the sensitivities of the selected BAP habitats to the range of possible saline flood events based on available knowledge. Taking an overview of all the matrices suggests that, in general, a flood event every 6 months to a year is the point at which the probability of habitat loss increases markedly. Less frequent events than this tend to have a much lower probability of habitat loss whilst the converse is true for more frequent events.

These matrices were used to inform the NaFRA modelling of risk of habitat loss, as described in Section 4.

Table 2.4a Reedbed Matrix (habitat only - not Table 2.4b Reedbed Matrix (accounting for faunal Table 2.5a High-Salinity Saline Lagoon Matrix Table 2.5b Low-Salinity Saline Lagoon Matrix accounting for faunal species interest) species interest)

Table 2.6 Eutrophic Standing Waters (Lakes) Matrix Table 2.7 Ponds Matrix Table 2.8 Coastal and floodplain grazing marsh Table 2.9 Grazing Marsh Grass Matrix (ditches)

Table 2.10 Lowland Fen Matrix Table 2.11 Wet Woodland Matrix Table 2.12 Purple Moor Grass and Rush Pasture Table 2.13 Lowland Raised Bog Matrix Matrix

2.3 Ease of creation of BAP habitats

Sea-level rise and the associated increased inundation of open-water and wetland BAP habitats located behind the natural and defended coastline are expected to result in losses of habitat areas. This will increase the difficulty of achieving existing BAP targets, such as the creation of 3,200 hectares of new grazing marsh and 3,000 hectares of reedbed, because there will be an implicit requirement to replace the habitat lost as well as create new areas of BAP habitat.

A simple categorisation of ease of practical habitat creation was developed to inform policy makers making decisions about habitat replacement. The aim of this task was therefore to develop a simple categorisation of ease of practical habitat creation which strategic decision makers can use to inform decisions about habitat creation initiatives, potentially in response to the modelling process and assessment of projected habitat losses under a range of climate change scenarios reported by this project.

The simple categorisation of ease of practical habitat creation has been taken to mean a ranking of the ease of creation of the habitats and also an indication of relatively how much easier or more difficult one habitat is to create than another. The task comprised two parts: to develop a set of criteria and associated scoring, against which the ease of habitat creation could be ranked; and then to undertake the scoring of habitats, and report the ranked list.

The project steering group was keen to obtain expert input to the development of the criteria and approach to scoring, and so this was discussed during the afternoon session of the workshop, referred to previously in Section 2.2.

2.3.1 Potential criteria for ranking ease of habitat creation

Background

There is a substantial literature on habitat creation from a number of recent habitat creation projects, including publications such as Habitat Creation and Repair (O.L. Gilbert and P. Anderson), Handbook of Ecological Restoration (M.R. Perrow and A.J. Davy), Habitat Creation – A Critical Guide (D.M. Parker), Wildlife Management and Habitat Creation on Landfill Sites (Ecoscope Applied Ecologists), Reedbed Management (C.J. Hawke and P.V. José), Wet Grassland Guide (P. Benstead, M. Drake, P. José, O Mountford, C. Newbold and J Treweek). The last work draws partly on research conducted during the early 1990s on behalf of Defra’s forerunner department (MAFF) where attempts were made to produce a provisional ranking of wetland NVC communities according to the ease with which they might be re-created. Useful information can also be obtained from publications such as Managing Habitats for Conservation (W.J. Sutherland and D.A. Hill) and the EC Life Project – Living with the Sea (http://www.eclife.naturalengland.org.uk/).

Potential criteria

A list of 14 potentially useful criteria was drawn up based on the literature and expert consultation. Six were screened out as not useful to the process primarily because they could not be scored simply. The remaining eight, indicated at the top of the list, in bold, were selected for discussion at the workshop.

An approach to scoring was then derived for each of the remaining eight criteria and the proposed approach was circulated to participants in advance of the workshop:

• Timescale: how long does it take to establish the BAP habitats?

• Size: is there a minimum extent required for habitat to be ecologically functional?

• Hydrological regime required by the BAP habitat: how demanding are the hydrological regime requirements of the BAP habitats?

• Substrates required by the BAP habitat: what are the substrate requirements of the BAP habitats and how readily are these encountered in the environment?

• Method of creation: what method of creation is required for each of the BAP habitats?

• Source of biological material to facilitate establishment of BAP habitat: what is the requirement for source material (e.g. natural succession etc.)?

• Trophic status: what is the trophic status of each habitat?

• Requirement for management during and after the habitat creation process: how intensive or specialised does the management need to be for each habitat?

• Topography required by habitats: what are the specific topographic requirements of the BAP habitats?

• Climatic requirements: do the habitats have any specific climatic requirements?

• Level of shelter or exposure tolerated by particular habitats: do particular habitats require sheltered or exposed locations or is no preference shown?

• Relative mobility/dispersability of key taxa characteristic of the BAP habitat: how mobile are the key taxa for each of the BAP habitats?

• Cost: how expensive is it to create a unit of each of the BAP habitats?

• Known difficulties in re-creating certain BAP habitats.

Workshop feedback

The participants were asked how the criteria and associated scoring should be amended. A number of useful general points were made highlighting issues that should be taken into account when planning any habitat creation. These included:

• Habitat creation should be planned for sustainable locations, as a plan to create habitat in an area that may be lost in a few years is probably not a good use of money. There was also a suggestion that: even if the habitat would only be present for a relatively short timescale, it still had potential value as a ‘stepping stone’ for species migration, etc.;

• Connectivity to existing similar habitats is important as a source for species;

• Trying to use precise criteria to determine what habitats to create may hamper habitat creation efforts. Opportunity is often the best criterion although where certain habitats require very specific environmental conditions a strategic approach should be taken to planning replacement habitats and these habitats should take precedence when opportunities arise;

• Habitats generally do not develop in isolation and habitat creation should ideally take a landscape- scale approach;

• Species’ re-introductions may only help recreate certain rarer habitats/ecosystems. The historic combination of environmental, climatic and management conditions may mean that areas such as the Norfolk Broads are now not re-creatable. It should also not be assumed that the habitats and species present in a given location now will be sustainable in that location in the future. Habitat creation is likely to fail its objectives if it has an aim such as to ‘create perfect S24 tall-herb fen that will still be present in 50 years’. It is more appropriate to take a more pragmatic approach and aim for what can be realistically achieved;

• Buffer habitats are important in providing opportunities for species to disperse and adapt to changes in habitat, land use, etc.;

• There may not be enough available space near the coast to re-create the unique habitats that currently occur as result of their proximity to the sea. As a result, replacement habitat created inland will be different to existing habitats that are at risk.

There were some concerns expressed about the level at which the assessment of creation criteria was being undertaken, i.e. BAP habitat level, both because of the wide variation in the requirements of component vegetation communities that constitute the habitats, and because there is a large amount of overlap between some of the habitats. It was suggested that the habitats should be sub-divided to allow for variations to be accommodated. However, as the project’s focus was on BAP habitat, the ranking must also be undertaken at this level. There were also concerns expressed about some of the proposed criteria. For example, the use of size (minimum extent) as a criterion was considered likely to drive policy towards creating habitats that required smaller areas. A similar concern was expressed over the use of time-scale, with the implication that it would drive policy towards creating habitats that are quickest to establish.

Overall, it was concluded that the approach proposed prior to, and discussed at, the workshop may be over-complex, and that it is already known which habitats can be created relatively easily (e.g. grazing marsh, reedbeds, ponds) and which are much more difficult to create or even impossible to create within timescales set by policy or legal requirements because of the difficulties in achieving the right soil conditions, species composition, water supply, etc. Lowland fens, lowland raised bogs, and wet woodland tend to fall into this category.

Approach adopted following the workshop

The observations of the participants were noted and the criteria were revisited. However, the project team felt that, although simplified criteria would still indicate the overall order of ease of habitat creation, if they were simplified far beyond those that were proposed for the workshop they would not adequately indicate how much easier or more difficult one habitat is to create than another. For example, although there were concerns that inclusion of timescale in the analysis would drive policy towards creating habitat that can be more quickly established, this criterion does need to be included to provide an indication of the difficulty (at least in terms of time taken) associated with the creation of a habitat that takes 50 to 100 years compared to one that takes five to nine years, for example.

Therefore, all of the criteria proposed at the workshop were retained and the final list of criteria used in the ranking is presented in Appendix H (Table H.1).

2.3.2 Ranking of ease of habitat creation

The final ranked list and the associated timescales for establishment of the habitats is presented in Table 2.15. The scores underlying the ranking are presented in Appendix H (Table H.2). The summary evidence and references supporting the scoring decisions are presented in Appendix I.

Table 2.15 Final ranked list of practical ease of habitat creation

Habitat Score (out of 50) Rank (Easiest to Timescale for Most Difficult) establishment

Eutrophic standing waters (lakes, ponds) 10 1 5-9 yrs

Reedbed 14 2 5-9 yrs

Saline lagoons 14 2 5-9 yrs

Wet woodland 16 4 10-50 yrs

Coastal and floodplain grazing marsh 17 5 5-9 yrs

Purple moor grass and rush pasture 20 6 5-9 yrs

Lowland fen 28 7 10-50 yrs

Lowland raised bog 43 8 50-100s of yrs

The ranking exercise indicates that eutrophic standing waters (lakes, ponds) are the easiest to create whilst lowland raised bog is by far the most difficult. In terms of the relative difficulty of creating the habitats, lowland raised bog scores as more than four times more difficult to create than eutrophic standing waters (ponds, lakes) and is nearly twice as difficult as fen, the next hardest habitat to create based on the scores. The scores for reedbed, saline lagoons, wet woodland and coastal and floodplain grazing marsh are all clustered together indicating that, on the basis of the criteria selected, these are about equally easy/difficult to create. The final ranked order is almost identical to that proposed during discussions with the experts at the workshop and seems sensible on the basis of knowledge of the issues and difficulties associated with habitat creation projects.

One of the key factors to be taken into account, particularly in respect of the ability to meet current BAP targets, is the number of years taken by a particular habitat to establish, which for lowland raised bog is likely to be 100s of years, whilst for the relatively easier habitats to create (e.g. ponds) it is less than 10 years (Table 2.15)11. This is an important consideration in respect of taking action to replace habitats projected to be lost as a result of climate change (see Section 4).

There is of course a degree of uncertainty with the ranked order and, moreover, with the assessment of relative ease/difficulty of habitat creation. Examples of issues encountered that have resulted in uncertainty include:

• Wide variability in the environmental requirements of the numerous communities that are included under the umbrella of each BAP habitat;

• Scientific uncertainty over the requirements of some habitats; for example, minimum size requirements or timescales for creation.

However, uncertainty has been minimised as far as possible by drawing on the expert knowledge of the project team, consulting with experts and making use of information from published sources (see Appendix I). When developing a ranking method the result is heavily reliant upon the criteria selected and the options developed for scoring. Confidence in the overall rank order derived for this project can be drawn from the fact that the attendees at the workshop produced an almost identical list based on their own knowledge. Although this was not a formal output of the workshop, it was a very useful indicator.

Confidence in the assessment of ease of habitat creation can be drawn from the fact that habitats known to be easily created are listed as such in the ranking, whilst habitats perceived to be difficult to create, such as fens and lowland raised bog, have received the highest scores.

There may be a debate about whether lowland raised bog is really just 4.3 times more difficult to create than a pond but the maximum differential possible is constrained by the scoring approach, which in this case has a minimum score of 8 and a maximum possible score of 50. Eutrophic standing waters (ponds, lakes) scored 10 (i.e. nearly the

11 There is further comment on the implications of the timescales required for the creation of BAP habitats in the context of progressing towards the current BAP targets in Section 5.

minimum possible), whilst lowland raised bog scored 43 (nearly the maximum possible). Against the criteria assessed, this is considered appropriate. Overall, it is considered that the final ranking compares favourably with similar lists published previously, but goes a step further than these in attempting to assess the relative practical ease/difficulty of creation, without focussing on cost.

Key - National Mapping

Reedbed

Saline lagoon

Key - Site Specific Mapping

Reedbed

Saline lagoon

Coastal Zone Adaptation to Climate Change

Figure 2.1 Comparison of National Mapped Habitat Data (top left) with Site Habitat Map (bottom right) Note: Reedbed appears to occupy a larger area in the national mapping than the March 2011 site-specific mapping. 24903-S19a.ai lowec

Based upon the Ordnance Survey Map with the permission of the Controller of Her Majesty’s Stationery Office. © Crown Copyright. Entec UK Ltd. AL100001776.

3. Modelling Approach

3.1 Context

The overarching purpose of the modelling was to assess the impact of climate change on the selected BAP habitats located in the coastal floodplain. The specific aims of the modelling were to:

• Provide a national assessment of the impact of sea-level rise on flood hazard in the coastal floodplain;

• Take into account a range of climate-change scenarios (high, medium and low emissions for different periods in the future) from UKCP09 data and consider the impact of maintaining or not maintaining coastal defences;

• Combine information from the habitat sensitivity assessment with the flood hazard assessment to assess the risk to habitats from potential future sea-level rise;

• Communicate the risk to habitats in terms of the potential area of habitat loss under a range of scenarios.

A risk based approach, which considers the probability and the consequences of a hazard occurring, has been used to model the impact of climate change on coastal BAP habitats. In this project, the hazard is flooding as a result of sea-level rise due to climate change and the consequence is the potential loss of BAP habitat that is exposed to the hazard. A national-scale flood risk model called RASP (Risk Assessment for Strategic Planning) has been applied in the study. The RASP approach has previously been used to carry out the National Flood Risk Assessment (NaFRA) for the Environment Agency to help strategic planning of investment in flood risk management. The NaFRA 2009 model results have been used as a basis for the modelling in this study.

The rationale for applying a risk-based approach rather than a deterministic approach in this project is that it enables an assessment of the overall level of impact to habitats from sea-level rise, rather than simply considering the impact that could arise from a single event of given probability (or return period) and given pattern of defence failure and habitat response. The risk-based approach takes into account the concept of the probability of a range of outcomes. Thus, the potential consequences of high-frequency, low-impact events can be considered alongside infrequent but extreme events. Different patterns of defence breach and overtopping are considered for each event and the response of the receptor (in this case, BAP habitat) is considered as a probabilistic variable which expresses the chance of loss of the habitat for a given flood condition.

The modelling approach uses the RASP model and NaFRA outputs to assess flood hazard for a range of sea-level rise scenarios and examines the consequences for each of the mapped BAP habitats using the their particular sensitivity matrices described in Section 2.2. To reiterate, these matrices were derived by expert judgement and referenced to empirical data. They give an estimate of the probability of irreversible change and the habitat loss for

different levels of flood hazard. The flood hazard is expressed as a combination of water depth and frequency of flooding. A simple calculation is used to derive duration from depth as these are the terms used in the sensitivity matrices. The following sections discuss general risk assessment concepts, provide details of the modelling approach used and describe how the model, sensitivity matrices and BAP habitat distribution data were used together to develop predictions of the extent of BAP habitat that might be lost under a range of flood scenarios. An overview of the modelling approach is provided in the flow chart in Box 3.1.

Box 3.1 Overview of Modelling Approach

AssessAssess SourcesSources –– determine determine coastalcoastal waterwater levelslevels forfor rangerange ofof returnreturn periodsperiods inin presentpresent dayday andand futurefuture periodsperiods usingusing UKCP09UKCP09 projectionsprojections AssessAssess PathwaysPathways –– evaluate evaluate chancechance ofof defencedefence overtoppingovertopping and/orand/or 1.1. AssessAssess FloodFlood HazardHazard breachbreach forfor eacheach waterwater level,level, consideringconsidering defencedefence type,type, crestcrest height,height, fragilityfragility andand conditioncondition (i.e.(i.e. whetherwhether defencedefence isis maintainedmaintained oror not).not). AssessAssess HazardHazard –– use use ofof floodflood spreadingspreading modelmodel toto calculatecalculate probabilityprobabilityofof experiencingexperiencing aa rangerange ofof depthsdepths overover thethe floodplain.floodplain. ConvertConvert depthdepth toto durationduration forfor useuse withwith habitathabitat sensitivitysensitivity assessment.assessment. HazardHazard frequencyfrequency isis givengiven byby probabilityprobability information.information.

HabitatHabitat mappingmapping –– vector vector datadata isis convertedconverted toto rasterraster data.data. 2.2. AssessAssess HabitatHabitat ExposureExposure SpatialSpatial analysisanalysis toto determinedetermine wherewhere habitathabitat isis presentpresent inin thethe samesame locationslocations asas potentialpotential hazardhazard occurrence.occurrence.

HabitatHabitat sensitivitysensitivity matricesmatrices givegive thethe probabilityprobability ofof lossloss forfor manymany combinations of flood frequency and duration. This project simply 3.3. AssessAssess ConsequenceConsequence combinations of flood frequency and duration. This project simply considersconsiders whetherwhether thethe habitathabitat willwill bebe lostlost asas aa resultresult ofof thethe floodflood hazard.hazard.

RiskRisk == ProbabilityProbability xx ConsequenceConsequence TheThe hazardhazard // habitathabitat lossloss probabilitiesprobabilities areare calculatedcalculated overover thethe fullfull 4.4. AssessAssess RiskRisk rangerange ofof possiblepossible outcomesoutcomes (frequent(frequent toto extremeextreme events)events) forfor eacheach climateclimate changechange scenario.scenario. ProbabilitiesProbabilities areare multipliedmultiplied byby thethe habitathabitat areaarea exposedexposed toto givegive totaltotal areaarea ofof habitathabitat loss.loss.

3.2 General risk assessment concepts

Risk is generally expressed as a combination of probability of a hazard occurring and the consequence arising from the hazard. The usual equation for representing risk is:

Risk = Probability × Consequence

Various conceptual models exist to represent and communicate the ideas involved in risk assessment. The Source-Pathway-Receptor-Consequence (S-P-R-C) model, diagrammatically shown in Figure 3.1 is a conceptual model that is commonly applied to flood risk assessment. It should be noted that the river flow and rainfall sources were not included in the coastal flood model used in this project.

The S-P-R-C model includes:

• Sources of flood risk: These include rainfall and river flow as well as coastal water level conditions. The coastal water level is the source being considered in this project and that is driven by the tides, surges, waves and currents that propagate to the coastal zone from the sea. The project is considering potential change to the source element by taking into account sea-level rise due to climate change;

• Pathways: These are the parts of the system that control the amount of water getting into the floodplain. They include barriers as well as natural routes for water to take, so take into account flood defences, sand dunes, shore platforms and cliffs;

• Receptors: These are the parts of the system that may be exposed to the flood hazard. As shown in Figure 3.1, receptors include urban infrastructure, industry, agriculture, amenity and the natural environment. The receptors considered in this project are the selected BAP habitats (see Section 2);

• Consequences: These are what happens to the receptors if they are exposed to a flood hazard. The consequence considered in this study is irreversible damage and complete loss of habitat. Other consequences for habitats that experience flooding include partial loss of ecosystem function, recoverable degradation of habitat and stress to species within the habitat. This study focuses on the risk of complete habitat loss to inform decisions about habitat creation requirements. Where there are obligations to maintain favourable conservation status (e.g. under the Habitats Directive), then partial loss or loss of function may still require replacement if recovery is not possible and it is recognised that these areas need to be considered in addition to the areas of loss estimated from this project.

The S-P-R-C model helps to explain how the assessment of the flood risk to habitat is carried out in this project. The steps in the risk assessment are:

1. Assess the probability of the flood hazard (with information on sources and pathways) to give the depth and extent of flooding for each return period event and climate change scenario. Flood duration is calculated from depth;

2. Assess receptor exposure by identifying where receptors are exposed to flood hazard;

3. Assess the consequences to the receptors by considering the sensitivity of the receptor to the magnitude of flood hazard encountered;

4. Assess the risk by considering the consequences over the full range of possible levels of flood hazard and taking into account the probability of occurrence.

The risk assessment calculates the average loss of habitat extent that could be experienced under each climate change scenario. It takes into account the probability of habitat loss from infrequent, extreme events as well as from smaller, frequent events. It is important to note that it does not translate to a loss that will be experienced every year but rather the average loss that may be experienced at any point in time given the climate change scenario. Actual losses over a year or a decade may be higher or lower, depending on whether a coastal flood event happens and how extreme the event is. The average loss figure takes into account this range of possible outcomes and represents, on average, the amount of habitat that should be created in order to compensate for the losses that could be experienced under the time periods being considered for this project.

3.3 The national flood risk assessment (NaFRA)

The National Flood Risk Assessment (NaFRA) has been carried out regularly by the Environment Agency to inform strategic flood risk management at a national scale. The risk is considered in terms of economic damages and helps the Agency to understand where there is an economic benefit from investment in flood defences. The flood modelling from NaFRA 2009 has been used in this project, with adjustments to the model to take into account habitat sensitivity instead of economic damages and also to account for sea-level rise. A step-by-step explanation of what the NAFRA model does is presented in Appendix J1. For a more detailed technical explanation, see Gouldby et. al. (2008).

3.4 Use of the UK climate projections 2009

The UK Climate Projections 2009 (UKCP09) present climate change projections for land and marine regions around the UK. The research was funded by Defra and is intended to help people and businesses understand what climate change will mean for them and start preparing adaptation measures where appropriate. UKCP09 incorporates the latest advances in climate change science and uses ensembles (sets of results) from a range of climate models to develop the range of change that may be expected for a number of climate variables such as temperature, precipitation and sea level rise. The outputs of UKCP09 aim to communicate the uncertainty associated with the climate projections and give results for low, medium and high carbon emissions scenarios. The projections are available for different time periods in the future. UKCP09 gives projections for 30-year time periods in the future; the 2030s relate to the period 2020-2049, the 2060s relate to the period 2050-2079 and the 2080s relate to the period 2070-2099.

The risk assessment carried out in this project applied the UKCP09 data on sea-level rise. For each climate change scenario, the UKCP09 projection of sea-level rise was applied to the coastal water levels for each return period. Regional data were used which take into account the variation of potential rises in sea level along the coastline in different parts of the country.

The climate change scenarios that this project considers include a range of high, medium and low emissions scenarios and time periods including the 2030s, 2060s and 2080s. Section 3.5 and Table 3.1 give full details of the scenario combinations modelled.

3.5 Assessment of risk to habitats

The risk to habitats from sea level rise due to climate change was considered with the RASP modelling process and the NaFRA 2009 model data. The general procedure was set out in Section 3.4. This section (3.5) explains the details of the method implementation that are specific to this project.

The scenarios that have been considered in this project include climate change over different periods of time and for different emissions scenarios as well as scenarios for defences maintained in their current condition or not maintained defences so that they degrade to poor condition (condition grade 5). Table 3.1 shows the combinations of scenarios that have been considered, as agreed with the project steering group. Each combination assumes that the location and amount of habitat remain unchanged from the present day situation (i.e. each scenario is modelled using the habitat mapping described in Section 2.1 of this report and does not take into account the potential creation or loss of habitat through other drivers and pressures before the periods chosen for the scenarios). Each scenario was given a code for ease of tabling results. The year, followed by L, M or H to indicate the UKCP09 emissions scenario low, medium or high, followed by M or D to indicate defence condition maintained or degraded.

Table 3.1 Risk assessment scenarios

Year Emissions Scenario Defence Management Scenario Code

2010 Present day Existing defence condition Current (2010)

2030 Medium emissions Defences maintained at existing defence condition 2030MM

Defences not maintained and degrade to poor condition 2030MD

2060 Low emissions Defences maintained at existing defence condition 2060LM

Medium emissions Defences maintained at existing defence condition 2060MM

Defences not maintained and degrade to poor condition 2060MD

High emissions Defences maintained at existing defence condition 2060HM

2100 (2080s UKCP09 Low emissions Defences maintained at existing defence condition 2100LM scenario) Medium emissions Defences maintained at existing defence condition 2100MM

Defences not maintained and degrade to poor condition 2100MD

High emissions Defences maintained at existing defence condition 2100HM

The model takes into account the different climate change periods and emissions scenarios by applying the relevant sea level rise from the UKCP09 projections data. The defence maintenance is taken into account through adjusting the defence condition grade that is allocated to each section of coastal defence. The ‘defences maintained’ scenarios make no changes to the condition grade. The ‘defences not maintained’ scenarios allocate a condition

grade of 5, the poorest grade, to each defence. This means that for this scenario the model applies defence fragility curves (see Appendix J1) which have a higher probability of breaching for a given water level.

The model results that are generated from NaFRA are depth-probability outputs. This is converted to duration- frequency outputs for direct use with the sensitivity matrices. It is recognised that using the standard outputs as proxies for duration and frequency is a simplification of reality, but this has been done as the duration and frequency characteristics of flooding are considered to be more important in determining whether a habitat will be affected by coastal flooding than consideration of water depth. The calculation of duration is made by a simple relationship between depth and topography and assumes that deeper flood water remains on the floodplain for longer and areas of higher or sloping ground will drain more quickly than areas of depression. The calculation of frequency is related to the probability outputs from the model. Since the model does not contain a sequential time aspect, a statistical distribution of the likely intervals between flood hazards associated with different probabilities has been applied to transform the data. It must be recognised that these methods for estimating duration and frequency from the model outputs are approximate and introduce an element of uncertainty to the risk assessment. All uncertainties are outlined in Section 3.9.

The risk assessment calculates the average loss of habitat area that could be experienced under each climate change scenario. It takes into account the probability of habitat loss from extreme events as well as from frequent events. It does not translate to a loss that will be experienced every year but rather the average loss that may be experienced at any point in time given the climate change scenario. Actual losses over a year or a decade may be higher or lower, depending on whether a coastal flood event happens and how extreme the event is. The average loss figure takes into account this range of possible outcomes and represents, on average, the amount of habitat that might need to be created in order to compensate for the losses that could be experienced now and at 2030, 2060 and 2100.

3.5.1 Current risk of habitat loss and further losses in the future

As the habitats considered in this study are mainly found within the coastal floodplain, there is a risk of habitat loss due to flooding now and there will remain a risk in the future. The amount of loss that represents the present day risk is, on average, the amount of habitat that may be lost at any time due to flooding under present day sea levels and the range of frequent and extreme events that can happen. This habitat loss due to potential flooding in the present day is the current risk. Over and above the current risk, there is an additional risk for each climate change scenario, so that the risk of habitat loss in 2100 is made up of the extent of habitat currently at risk of loss plus an additional loss due to the rise in sea level from climate change.

3.6 Modelling calculation: worked example

This section provides a more detailed description of the steps involved in the modelling and is also the subject of a Technical Note released as a complimentary project output (HR Wallingford, 2011). The modelling approach used

in this study takes into account the best-available expert understanding of habitat sensitivity to two aspects of coastal flooding; flood duration and flood frequency.

The modelling methodology is presented in the form of a worked example, in Appendix J2. For the purposes of this illustrative example, this area has been referred to as ‘Site X’ which supports ‘Habitat X’.

To estimate the risk to habitat of coastal flooding, the National Flood Risk Assessment (NaFRA) outputs are combined with habitat sensitivity matrices. NaFRA estimates the probability of flooding exceeding a range of depths for several combinations of coastal water level and defence condition. These flood depths are then converted to flood durations (as described below), which are used with the habitat sensitivity matrices to estimate the probability of habitat loss depending on flood duration and frequency.

Outputs from the model are at the 50 m model grid square level but these have been aggregated to a 5 km square grid scale for mapping outputs. This aggregation has been undertaken as the representation of variation between neighbouring 50 m grid squares is highly uncertain. Consequently, it would not be appropriate for the mapped outputs to be available at the smaller scale for use in local habitat management. The results tables presented in Section 4 however are based on the 50 m resolution model outputs.

3.7 Comparison of outlined methodology with existing approaches

The approach adopted in this study to estimate habitat risk is probabilistic, rather than the deterministic approaches used in similar studies previously which may often have used results derived from NaFRA, or other probabilistic flood studies.

A deterministic approach gives information about habitat exposure to inundation under an extreme event (1 in 1,000 years) which does not take into consideration the conditions that may lead to habitat loss. This deterministic calculation is quick to perform, but provides a less realistic depiction of any physical systems in which uncertainty is important. When making projections of likely habitat loss into the future, uncertainty becomes increasingly important and the deterministic assumption less appropriate.

A probabilistic approach, by contrast, is one that helps quantify risk in systems that are inherently uncertain. Rather than assuming that a specific extreme event will occur, and that it will result in habitat loss, the approach outlined considers a full range of events for which a full range of outcomes is possible. For each event, the consequence is estimated and the risk for all events can be aggregated into a single expected value, weighting each according to their likelihood of occurrence. In such approaches, an extreme flood outline (1:1,000-year tidal and tidal/fluvial flood zone 2) has typically been used to estimate the area of habitat ‘at risk’, as shown in Figure 1.1.

Deterministic and Probabilistic events are inherently different, and produce different results. While a probabilistic approach is arguably more powerful than a deterministic approach, it requires more data to perform and is significantly more complex.

3.8 Quality audit

With several steps involved in the modelling of risk to habitats from sea-level rise and a range of data types and data sources being used in the modelling, it was important to ensure that the data and modelling steps are appropriately audited to ensure that data is correct to the best available knowledge and that the modelling process has been implemented correctly and that computing algorithms have run successfully. Quality control checking was been carried out at all data collation, analysis and modelling process steps in the project. These audit activities check that the project method has been implemented correctly; they do not remove the uncertainties relating to the model outputs, which are described in Section 3.9.

The points of audit, where checking was carried out were:

• Habitat mapping - Section 2 provides an overview of the checks carried out and the solutions implemented to improve data quality as far as possible. Habitat mapping was checked for repetition of areas in multiple habitat layers, checking of data attributes and verification of national datasets with regional and site datasets (removal of overlaps and possible double counting);

• NaFRA outputs - The NaFRA data was mapped to check for anomalies in the outputs and data was also examined for appropriate database structure and that the exporting processes had executed correctly;

• Sea-level rise projections - Coastal water levels applied for each model scenario were checked to ensure that the UKCP09 projections for sea-level rise were correctly applied to the NaFRA coastal water levels for each coastal catchment;

• One additional sea-level rise scenario was modelled as a sensitivity check on the model results presented. This comprised the 2100 high emissions scenario + 0.5 metres of sea-level rise;

• Defence failure - The calculation of overtopping volumes and breach volumes was checked by verifying that the model process for applying overtopping lookup tables and breach fragility curves had been implemented correctly for a random selection of defence sections;

• Flood spreading and calculation of hazard probabilities - The log files for the flood spreading model and calculation of probabilities of depths and subsequent calculation of duration were checked for successful running of the model code (i.e. checked that there were no computation failures and that model iterations ran to appropriate numbers);

• Habitat exposure and sensitivity look-up - A spot check of calculation of habitat loss for different habitat locations was carried out to ensure that risk was being calculated where habitat was exposed to flood hazard and to audit the process of implementing model code to calculate loss for a given model cell;

• Summing habitat loss figures for total habitat area - An audit of the model process was conducted to verify that addition of model outputs at cell level had been aggregated appropriately for the outputs presented.

The quality checking steps for the modelling included a check that correct input data is used, a check that correct model code was used, a check on the processing log file to ensure that the computation ran correctly and a check that results were plausible and sensible.

3.9 Uncertainty

Uncertainty is a general concept that reflects our lack of sureness about an outcome. Understanding the uncertainty within predictions and decisions is central to understanding risk. Aspects of uncertainty include:

• Lack of knowledge of the nature and behaviour of the physical world (knowledge uncertainty);

• Inherent variability in the physical world (natural variability);

• Complexity of social/organisational values and objectives (decision uncertainty).

Consideration of uncertainty within the decision process attempts to quantify our lack of sureness, and thereby provide the decision maker with additional information on which to base a decision. The risk assessment approach applied in this study attempts to quantify and take into account the natural variability aspect of uncertainty, through the probabilistic approaches to considering floods with different return periods and different possible defence failure patterns. The model takes natural variability into account in the average loss outputs. The projected loss figures give a general overview of the risk and the actual loss of habitat may be higher or lower as a result of natural variability.

Knowledge uncertainty includes the lack of accuracy of numerical models in representing the actual physical processes. This type of uncertainty can be reduced with models that provide a better mathematical representation of the processes, which generally involves the use of more sophisticated models. There is, however, a balance between the most accurate model of a natural process (which remains an uncertain representation of the process) and the time it takes to run a model at the scale of interest. There is considered to be no benefit in running a model of climate change impact on flooding that would take 100 years to compute results. It is recognised that the techniques implemented on this project are subject to a range of uncertainties in relation to how accurately they represent the natural world; but they provide the most practical means of understanding risk at a national scale.

The main areas of uncertainty in the modelling are:

• The UKCP09 projections are based on the best available climate models but there remains high uncertainty related to what amounts of sea-level rise will actually be experienced in the future;

• NaFRA splits the English coast into 49 sections and applies defence loadings along these sections. In reality there will be local variations in levels, surge and wave action that are smoothed out by the model;

• NaFRA uses the national flood and coastal defence data (NFCDD) and associated fragility curves to model defence failure and overtopping. The model is based on most recent surveys of defences but in

some cases, defence state may have degraded or improved since surveying, which is not taken into account. The fragility curves represent best available science to describe defence response to flooding but the application of these general rules do not model the specific mechanics of each section of defence at the coastline;

• The model simulates flooding from sea-level rise but does not take into account the potential loss of habitat from accelerated coastal erosion and step changes in coastal morphology (other than locations that become fully submerged due to sea-level rise);

• NaFRA uses the RFSM to spread water over the floodplain and this model provides a simplified approach to simulating natural processes and therefore does not pick up detailed flood patterns in areas of complicated terrain;

• The techniques developed for this project use depth as a proxy for duration, which was used to develop the habitat sensitivity matrices. The method for calculating duration is associated with high uncertainty as it simply takes into account flood depth and topography; changes in land use, soil type and soil moisture have a strong influence on flood retention times and are not taken into account;

• There are limitations with the habitat mapping, as outlined in Section 2, and high uncertainty in relation to the total area and location of each habitat;

• The use of the habitat sensitivity matrices is associated with high uncertainty as they are based on expert judgement with little evidence on the actual impacts of flooding on these habitats. There is uncertainty over the relationship between complete habitat loss and loss of site integrity.

Decision uncertainty is a state of rational doubt as to what to do. The response to the potential risks arising from climate change are associated with decision uncertainty; it cannot be certain that the measures put in place now will adequately address the actual risks that are realised in the future. For example, if defences are built now, it is uncertain as to whether they will provide adequate flood protection in the future. Decision uncertainty can be influenced by the reversibility of the decision and the robustness of the decision to change. Decisions should aim to be flexible and adaptable to different potential outcomes in the future.

In practice, these aspects of uncertainty mean that any policy responses to the outputs of this project have to take on board that the actual reality of habitat loss due to sea-level rise in the future may be higher or lower than the figures presented in this report. This project provides an indicative overview of the level of risk at a national scale, and applied the best information available to reach consensus on the habitat sensitivities to frequency and duration of flooding. It provides a basis for long term adaptation planning. Adaptation decisions should be flexible so that management actions can be adjusted to deal with actual outcomes. The probabilistic, risk-based approach brings advantages compared to a deterministic approach as it explicitly recognises the uncertainty related to what actual future outcome will be and takes into account that there is a low chance of experiencing very extreme events and a higher chance of experiencing less severe flooding. There remain, however, uncertainties with each element of the modelling (as outlined above), which would exist for any modelling or analysis approach taken.

Coastal Zone Adaptation to Climate Change

Figure 3.1 The Source - Pathway - Receptor - Consequence Model of Flood Risk Assessment

March 2011 24903-S20a.ai lowec Key Coastal Zone Adaptation to Climate Change Vector Representation of Site X Figure 3.2 Habitat X at Site X

March 2011 0km 1km 24903-S21a.ai lowec

4. Assessment of the area of BAP habitat at risk of loss as a result of coastal flooding

4.1 Context

The aim of this section is to report the projected extents of priority BAP habitats at risk of loss as a result of coastal inundation for each of the modelled climate-change scenarios to enable policy makers to examine the scale of possible habitat losses in the context of areas protected under the Wildlife and Countryside Act (1981) and also in respect of meeting European Union obligations under the Habitats and Birds Directives and International agreements (e.g. Ramsar). At the national scale, the range of outputs derived comprises areas of habitat at risk within the coastal floodplain (see Figure 1.1) by combinations of climate-change scenario (from current to the year 2100) and condition of flood defence, and grouped according to whether the habitat was:

• Within or outwith designated sites combined;

• Within SSSIs;

• Within SACs;

• Within SPAs;

• Within Ramsar sites;

• Within SAC/SPA/Ramsar sites combined;

• Within non-designated areas.

Regional-scale outputs have also been developed for potential losses of each type of habitat for each modelled scenario within each Environment Agency region. Regional outputs have not been derived for the different designations because the areas of most habitats at risk of loss are already relatively small when disaggregated at a regional scale.

4.2 Assessment of areas of BAP habitat at risk of loss

The model-derived extents for areas of habitat at risk of loss on a national basis, within and outside designated areas are presented in Table 4.1, whilst those for SSSI and SAC/SPA and Ramsar combined are presented in Tables 4.2 and 4.3 respectively. The habitat extents at risk of loss within each type of designated area and outside designated areas are presented in Tables K1-K4 in Appendix K. Regional analyses of losses are tabulated in Appendix L, Tables L1-L7.

The figures in the tables represent the average loss that could be experienced under each climate change scenario and hence the average amount of habitat that might need to be created in order to replace habitat that is at risk of complete loss due to flooding from sea-level rise. The figures take into account the probability of habitat loss from extreme events as well as from frequent events. They do not translate to a loss that will be experienced every year but rather the average loss that may be experienced at any point in time given the climate change scenario. Actual losses over a year or a decade may be higher or lower, depending on whether a coastal flood event happens and how extreme the event is. The projected average loss figure takes into account this range of possible outcomes and represents, on average, the amount of habitat that might need to be created (assuming that habitat replacement is required if there is complete loss of a habitat) in order to compensate for the losses that could be experienced now and additionally at 2030, 2060 and 2100. For reedbed, an assessment was also made of the risk of loss of faunal interest from the habitat based on a sensitivity matrix that was constructed considering the effects of saline flooding on the fauna specifically (i.e. the reedbed may survive, but the faunal interest may be lost). This is one example, since it was outside of the scope of this study to examine sensitivities for faunal losses for all habitats.

It can be noted that there are a few situations where a reduced risk is indicated in the results. These situations are indicated by an R in the tables but are in general around 1ha in size and are well within the likely margin of error of the modelling. The results with these R values should therefore be interpreted as ‘no change in risk’ compared to the current (2010) situation.

Table 4.1 Extents of all selected BAP habitats within the coastal floodplain at risk of loss

Habitat Total Habitat Current Projected additional risk to all selected BAP habitats resulting from climate change scenarios (Ha) (Ha) in Risk (Ha) Interpretation: The average loss of fens under scenario ‘2100 medium with defences maintained’ would be 29ha (current) + 5ha (additional risk) = 35ha. coastal floodplain 2010 2030MM 2060LM 2060MM 2060HM 2100LM 2100MM 2100HM 2030MD 2060MD 2100MD

CFPGM Grassland 87,581 3919 340 393 421 424 456 477 512 526 715 823

CFPGM Ditches 3,649 127 3 13 14 15 16 17 19 22 25 30

D. Wood 5,768 191 6 23 27 29 34 39 52 38 42 56

LRB 2,898 106 25 41 41 41 41 41 41 80 95 96

Reed (species) 2,564 103 9 18 18 21 20 23 24 21 20 25

Ponds 1,889 60 5 9 9 10 12 11 13 14 14 18

Reed (habitat) 2,564 39 5 9 9 11 10 12 13 10 10 12

Lakes 1,511 33 4 3 3 3 4 4 5 5 5 7

Fens 1,964 29 1 1 1 1 1 1 1 5 5 5

PMGRP 85 3 0 1 1 1 1 1 1 0 1 1

SL 1,112 0 0 0 0 0 0 0 0 0 0 0

Totals 109,020 4,571 393 502 537 544 586 614 668 711 923 1060 Habitat codes: LRB – Lowland raised bog, CFPGM – Coastal and floodplain grazing marsh, SL – Saline lagoons, Reed (habitat) – reedbed habitat only, Reed (species) – reedbed taking faunal species interest into account, PMGRP – Purple moor grass and rush pasture, D. wood – Deciduous wood Scenario references are year, UKCP09 emission scenario (L = low, M = medium, H = high), defence status (M = maintained, D = degraded) Figures represent the average complete loss in area of habitat that could be experienced under each climate change scenario. Habitats ordered by extent of habitat at risk of loss. Total pond extent is presented, not priority ponds. It is estimated that around 20% of ponds nationally will be priority ponds. However, this percentage rises when ponds are located in designated sites.

Table 4.2 Extents of all selected BAP habitats within SSSIs in the coastal floodplain at Risk of Loss

Habitat Total Habitat Current Projected additional risk to all selected BAP habitats in SSSI resulting from climate change scenarios (Ha) (Ha) in Risk (Ha) Interpretation: The average loss of fens under scenario ‘2100 medium with defences maintained’ would be 26ha (current) + 5ha (additional risk) = 31ha. coastal floodplain 2010 2030MM 2060LM 2060MM 2060HM 2100LM 2100MM 2100HM 2030MD 2060MD 2100MD

CFPGM Grassland 30,279 1122 164 208 215 221 232 244 254 305 362 400

CFPGM Ditches 1,262 44 5 8 8 9 9 10 11 15 14 16

LRB 2,873 106 18 35 34 35 34 35 35 72 87 88

D. Wood 2,791 94 3 9 13 13 17 16 20 26 24 26

Reed (species) 2,416 91 6 17 17 18 18 20 21 20 18 21

Reed (habitat) 2,416 34 5 9 9 10 10 11 12 10 10 11

Ponds 453 27 0 3 3 3 4 4 4 6 5 6

Fens 1,939 26 1 1 1 1 1 1 1 4 4 5

Lakes 807 21 R 0 0 0 0 0 1 1 1 1

PMGRP 2 0 0 0 0 0 0 0 0 0 1 1

SL 959 0 0 0 0 0 0 0 0 0 0 0

Totals 43,781 1531 196 281 292 299 317 330 347 449 514 563 Habitat codes: LRB – Lowland raised bog, CFPGM – Coastal and floodplain grazing marsh, SL – Saline lagoons, Reed (habitat) – reedbed habitat only, Reed (species) – reedbed taking faunal species interest into account, PMGRP – Purple moor grass and rush pasture, D. wood – Deciduous wood Scenario references are year, UKCP09 emission scenario (L = low, M = medium, H = high), defence status (M = maintained, D = degraded) Figures represent the average complete loss in area of habitat that could be experienced under each climate change scenario. Habitats ordered by extent of habitat at risk of loss. Total pond extent is presented, not priority ponds. It is estimated that around 20% of ponds nationally will be priority ponds. However, this percentage rises when ponds are located in designated sites.

Table 4.3 Extents of all selected BAP habitats within SAC/SPA and Ramsar sites combined in the coastal floodplain at risk of loss

Habitat Total Habitat Current Projected additional risk to all selected BAP habitats in SAC/SPA and Ramsar combined resulting from climate change (Ha) in Risk (Ha) scenarios (Ha) coastal Interpretation: The average loss of fens under scenario ‘2100 medium with defences maintained’ would be 26ha (current) + 5ha (additional risk) = 31ha. floodplain 2010 2030MM 2060LM 2060MM 2060HM 2100LM 2100MM 2100HM 2030MD 2060MD 2100MD

CFPGM Grassland 24,397 1112 74 199 202 207 217 229 238 169 350 383

CFPGM Ditches 1,017 44 4 7 7 7 8 8 10 11 12 15

LRB 2,831 96 22 35 39 43 49 49 49 74 86 87

Reed (species) 2,121 81 9 16 16 17 18 20 21 19 17 21

D. Wood 2,260 63 6 11 13 13 16 16 18 19 26 26

Reed (habitat) 2,121 31 6 9 10 10 11 12 12 11 10 11

Fens 1,843 26 1 1 1 1 1 1 1 4 4 5

Ponds 376 24 1 2 3 3 4 4 4 5 5 6

Lakes 713 21 R 0 0 0 0 0 1 1 1 1

PMGRP 1 0 0 0 0 0 0 0 0 0 0 0

SL 907 0 0 0 0 0 0 0 0 0 0 0

Totals 36,466 1467 116 271 281 291 313 327 342 302 501 544 Habitat codes: LRB – Lowland raised bog, CFPGM – Coastal and floodplain grazing marsh, SL – Saline lagoons, Reed (habitat) – reedbed habitat only, Reed (species) – reedbed taking faunal species interest into account, PMGRP – Purple moor grass and rush pasture, D. wood – Deciduous wood Scenario references are year, UKCP09 emission scenario (L = low, M = medium, H = high), defence status (M = maintained, D = degraded) Figures represent the average complete loss in area of habitat that could be experienced under each climate change scenario. Habitats ordered by extent of habitat at risk of loss. Total pond extent is presented, not priority ponds. It is estimated that around 20% of ponds nationally will be priority ponds. However, this percentage rises when ponds are located in designated sites.

4.3 Headline observations

Over half of the national resource of coastal and floodplain grazing marsh, reedbed and saline lagoons in the derived alternative habitat inventories are situated in the coastal floodplain.

It is also worthy of note that the composition of BAP habitat in coastal areas will be influenced by the coastal environment and hence will often be different from those located in more inland locations. Therefore, although the extent of a number of the other habitats located in the coastal situations is relatively small in terms of their percentage of the national resource, the fact that habitats with a particular coastal character comprise a relatively small amount of the national resource places additional value on these, thus reinforcing the importance of the coastal zone in supporting these priority BAP habitat types.

Potential losses of BAP habitat from the coastal floodplain are therefore of great significance, not just for the habitats of the coastal zone but also for the species that these will support.

4.3.1 Habitats at risk of loss within the coastal floodplain

Figure 4.1 illustrates that, under the highest projection (2100 medium with degraded defences scenario), habitat losses are focussed along the eastern coast of England, around the Thames estuary and south-east coast and on the southern side of the Severn estuary. Up to 20% of all the selected BAP habitats are at risk of loss under the projection presented although there are localised areas where average projected losses could be higher, notably on the north Norfolk coast, Essex and on the south coast. The other scenarios show a similar distribution but with lower average projected losses.

Figures 4.2-4.4 present projected losses of coastal and floodplain grazing marsh, lowland raised bog and deciduous woodland respectively, in different regions of the country under the 2100 medium with degraded defences scenario. Figure 4.2 illustrates that there are significant areas and percentages of the total coastal and floodplain grazing marsh resource at risk of loss in individual 5 km x 5 km grid cells in East Anglia whilst significant areas and percentages of the total lowland raised bog resource are at risk in the individual grid cells in the Humberhead levels (Figure 4.3) but generally lower areas and percentage of deciduous woodland are at risk in the south east (Figure 4.4).

More detailed observations on the assessment of habitats at risk of loss within the coastal floodplain are that:

• Of the 109,020 ha (1,090 km2) of habitat present in the coastal floodplain, an average of 4,571 ha (45.7 km2 - 4.2%) are at risk of loss under climatic conditions prevailing currently (2010). This is around 81% of the total selected BAP habitat at risk under any scenario;

• The extent at risk of loss increases 9% (393ha) at 2030 (2030 medium with defences maintained), 12% at 2060 (2060 medium with defences maintained) and 13.5% at 2100 (2100 medium with defences maintained). This increases 23% under the highest projection, 2100 medium with degraded defences,

to an average of 5,631 ha (56 km2) which is 5.1% of the total habitat resource. This is a significant increase in projected possible losses over the next 90 years;

• Of the selected habitats in the floodplain, coastal and floodplain grazing marsh is projected to lose the greatest area, with an average loss of 3,918 ha (4.5% of the total area of this habitat in the coastal floodplain) at risk under climatic conditions prevailing currently, an average of 4,389 ha (4.8% of the total area of this habitat in the coastal floodplain) at risk in 2030 (under the 2030 medium with defences maintained projection) and an average loss of 4,742 ha (5.4% of the total area of this habitat in the coastal floodplain) at risk under the under the highest projection, 2100 medium with degraded defences. Coastal and floodplain grazing marsh comprises 86% of the area at risk of loss under current climatic conditions and 84% under the highest projection, 2100 medium with degraded defences;

• The climate-change scenarios modelled to 2100 are set to increase habitat losses by up to 47% compared to the habitat areas at risk currently. For example, under the 2100 medium with degraded defences scenario, 47% more lowland raised bog is projected to be at risk of loss compared to the current scenario. However, not all habitats are affected to the same degree. For example, the figure for coastal and floodplain grazing marsh is an additional 17% at risk of loss, and for deciduous woodland the figure is 22%. It is also important not to overlook significant increases in the average losses that could occur earlier than 2100, for example the average extent of lowland raised bog at risk of loss in 2030 (medium with defences maintained scenario) is increased 19% compared to the climatic conditions prevailing currently;

• The habitat that is at greatest risk of loss in percentage terms under the current climatic conditions is grazing marsh grass habitat (4.9%) although this changes to lowland raised bog under the highest projection, 2100 medium with degraded defences, with an average 7% loss;

• Two sensitivity matrices were derived and applied to reedbeds. The effects of the different sensitivity matrices are illustrated in the results, with an average of 39 ha at risk of loss under current climatic conditions when the sensitivity matrix accounts for the reedbed habitat only, and an average of 103 ha at risk of loss when the sensitivity matrix accounts for faunal species interest;

• There is no projected loss of saline lagoons. However, this is perhaps not surprising given the general insensitivity of this habitat to loss following inundation as indicated by the sensitivity matrix;

• There is very little projected loss of fens and reedbeds (not accounting for faunal species sensitivity) under climatic conditions currently prevailing, in both aerial extent (average 29 ha and 39 ha respectively) and also percentage extent (1.5% for both). This is likely to be due to the use of the same sensitivity matrix for lowland fen and reedbed habitat.

Although it appears at first that the habitat extents assessed as being at risk are not as large are previous studies have suggested, it must be remembered that this project has identified those areas at risk of loss, not simply those that may be exposed to flooding, which has been the approach of previous studies, such as NEOCOMER (Defra, 2006). For example, the NEOCOMER study suggested that 32,300 ha of BAP habitat were present in designated sites within 14 km of the coast, were being protected by coastal defences and might need to be re- created as a result of future flooding due to climate change and sea-level rise. However, this study assumed that exposure to saline inundation of any duration would result in habitat loss. In addition to a more sophisticated

modelling method that takes into account floodplain topography and a range of flood events, the current study uses the sensitivities of the habitats to saline inundation events as an additional step in the analysis. The current project has calculated that 109,020 ha of the selected BAP habitats are present in the coastal floodplain, of which an average of 5,631 ha is at risk of loss under the highest projection (2100 medium with degraded defences scenario). Whilst not as great as the NEOCOMER study, the average extent of habitat at risk of loss identified by this project under the highest projection (2100 medium with degraded defences scenario) are not insignificant at an area equivalent to approximately 11,200 football pitches or 1.2 times the area of the city of Oxford.

4.3.2 Habitats at risk of loss within designated sites in the coastal floodplain

Based on the habitat mapping derived for this project, 40% of the BAP habitats located within the coastal floodplain are located within SSSIs. SAC, SPA and Ramsar sites (combined) contain 33% of the BAP habitat located within the coastal floodplain.

Key observations on the assessment of habitats at risk of loss within designated sites are that:

• Of the 43,781 ha (438 km2) of habitat present in SSSIs in the coastal floodplain, an average of 1,531 ha (15.3 km2 - 3.5%) are at risk of loss under climatic conditions prevailing currently (2010). This is around 73% of the total selected BAP habitat at risk under any scenario in SSSIs;

• The extent at risk of loss increases by 13% (196 ha) at 2030 (2030 medium with defences maintained), 19% at 2060 (2060 medium with defences maintained) and 22% by 2100 (2100 medium with defences maintained). This increases by 37% under the highest projection, 2100 medium with degraded defences, to an average of 2,094 ha (21 km2) at risk under the highest projection (2100 medium with degraded defences) which is 4.7% of the total habitat resource. This is a significant increase in projected possible losses over the next 90 years;

• The habitat that is at greatest risk of loss, in respect of overall extent, is coastal and floodplain grazing marsh, with an average of 1,122 ha (3.7%) at risk under climatic conditions prevailing currently, an average of 1286 ha (4.2% of the total area of this habitat in the coastal floodplain) at risk in 2030 (under the 2030 medium with defences maintained projection) and an average loss of 1,522 ha (5%) at risk under the under the highest projection (2100 medium with degraded defences). Coastal and floodplain grazing marsh comprises 73% of the total area of all habitats at risk of loss under current climatic conditions and 73% under the highest scenario (2100 medium with degraded defences). The slightly lower contribution of coastal and floodplain grazing marsh to the total area of habitat at risk of loss within SSSIs compared to the total areas in the floodplain is indicative of the slightly lower contribution of this habitat to the total habitat resource within SSSIs (69% of habitat within SSSI compared to 80% across the tidal and tidal/fluvial floodplain);

• The climate change scenarios modelled are likely to increase habitat losses by similar percentages within designated sites as within the wider coastal floodplain. As for the wider coastal floodplain, it is the lowland raised bog that is at greatest risk, expressed in terms of its percentage extent in SSSIs, at 6.8% under the 2100 medium with degraded defences scenario; and

• Areas at risk of loss within SAC/SPA and Ramsar sites combined are very similar to those for SSSIs (compare Table 4.3 with Table 4.2), despite supporting 16% less habitat than SSSIs within the coastal floodplain. It is likely that the majority of the SAC/SPA and Ramsar areas within the coastal floodplain are located close to the coast whilst the SSSI may be more widely spread and hence this may result in proportionately greater risk of loss in these sites compared to the SSSI.

4.3.3 Habitats at risk of loss in Environment Agency regions in the coastal floodplain

Tables L1-L7 indicate the total area of lowland open-water and wetland BAP habitat within each of the Environment Agency regions, and also how much of this is at risk of loss under current climate conditions and under the modelled future scenarios. Key observations on the tables are that:

• The Agency’s South-West Region has the greatest extent of habitat located within the coastal floodplain (34,915 ha), with Anglian supporting the next greatest amount (29,255 ha). Thames Region has the least, at 600 ha;

• With respect to average areas at risk of loss, South-West and Anglian are almost identical under current climate conditions (1,635 ha for South-West and 1,634 ha for Anglian) but a little more habitat is indicated to be at risk of loss in Anglian compared to the South-West under future climate change conditions (2073 ha at risk in Anglian under the 2100 medium with degraded defences scenario compared to 2,013 ha in the South-West). A figure of 1,635 ha amounts to 36% of all the habitat at risk across the country under current climate conditions and the total at risk under the 2100 medium with degraded defences scenario is a similar percentage. Midlands and Thames Regions have less than 50 ha of habitat assessed to be at risk of loss under all the scenarios, whilst the figure for the North-East Region is less than 250 ha.

200000 400000 600000 200000 400000 600000 Key Area of Selected Habitat at Risk (ha) in 1 in Percentage of Selected Habitat Area at Risk in 1 in Area of Selected Habitat at Risk (ha) 1,000 year tidal and tidal/fluvial flood zone 2 1,000 year tidal and tidal/fluvial flood zone 2 (per 5km square grid cell)

800000 800000 800000 0 - 10

N 11 - 25

26 - 50

51 - 100 600000 600000 600000 101 - 250

Percentage of Selected abitat Area at Risk (per 5km square grid cell)

0% - 20%

21% - 40% 400000 400000 400000

41% - 60%

61% - 80%

81% - 100%

Note: 200000 200000 200000 The extent of blue shows the areas of habitat at risk of loss under the scenario.

0 200 Kilometers Scale: 1:7,000,000 @ A4 G:\MODEL\PROJECTS\EA-210\24903 Coastal Biodiversity and Climate Change\ArcGIS\Figures\24903-S07d_Scenario11 Area %.mxd 0 0 0 Coastal Zone Adaptation to Climate Change Figure 4.1 Area & Percentage of Selected Habitat at Risk of Loss under 2100 Medium with Degraded Defences Scenario in 1 in 1,000 year Tidal and Tidal/Fluvial -200000 -200000 -200000 Flood zone 2

March 2011 200000 400000 600000 200000 400000 600000 24903-S07d stokr

Based upon the Ordnance Survey Map with the permission of the Controller of Her Majesty's Stationery Office. © Crown Copyright. AL100001776 500000 600000 500000 600000 500000 600000

Coastal and Floodplain Grazing Coastal and Floodplain Grazing Marsh Coastal and Floodplain Grazing Marsh Marsh in 1 in 1,000 year tidal and Area at Risk (ha) in 1 in 1,000 year tidal Percentage Area at Risk in 1 in 1,000 tidal/fluvial flood zone 2 and tidal/fluvial flood zone 2 year tidal and tidal/fluvial flood zone 2 400000 400000 400000 400000 300000 300000 300000 300000 200000 200000 200000 200000

500000 600000 500000 600000 500000 600000

Key Area of Coastal and Floodplain Percentage Area of Coastal and Coastal Zone Adaptation Grazing Marsh at Risk (ha) Floodplain Grazing Marsh at Risk to Climate Change Coastal and Floodplain Grazing Marsh in 1,000 year tidal and tidal/fluvial flood zone 2 1 - 10 1 - 20 Figure 4.2 Note: Environment This is a snapshot of Coastal and Floodplain Coastal and Floodplain Grazing Marsh Agency Region 11 - 25 20 - 40 Grazing Marsh habitat at risk, focussed on Extent and Areas at Risk Under the Environment Agency Anglian Region Scenario 2100 Medium with Degraded Coastal and Floodplain 26 - 50 40 - 60 Grazing Marsh Area and percentages of habitat at risk Defences in 1 in 1,000 year tidal and presented are per 5km square grid cell. 51 - 100 60 - 80 tidal/fluvial flood zone 2 in Environment 1 in 1,000 year tidal and Agency Anglian Region tidal/fluvial flood zone 2 100+ 80 - 100 0 100 Kilometers March 2011 G:\MODEL\PROJECTS\EA-210\24903 Coastal Biodiversity and Climate Change\ArcGIS\Figures\24903-S16c_CFPGM_Risk.mxd Scale: 1:2,750,000 @ A4 24903-S16c stokr

Based upon the Ordnance Survey Map with the permission of the Controller of Her Majesty's Stationery Office. © Crown Copyright. AL100001776 300000 400000 500000

Lowland Raised Bog in 1 in 1,000 year tidal and tidal/fluvial flood zone 2 400000 400000

300000 400000 500000

Lowland Raised Bog Area at Risk (ha) in 1,000 year tidal and tidal/fluvial flood zone 2 400000 400000

300000 400000 500000

Lowland Raised Bog percentage Area at Risk in 1,000 year tidal and tidal/fluvial flood zone 2 400000 400000

Note: This is a snapshot of Lowland Raised Bog habitat at risk, in Northern England.

Area and percentages of habitat at risk presented are per 5km square grid cell.

300000 400000 500000 Key Area of LRB Risk (ha) Percentage Area of Coastal Zone Adaptation Lowland Raised Bog to Climate Change Lowland Raised Bog in 1,000 year 1 - 10 Risk tidal and tidal/fluvial flood zone 2 1 - 20 11 - 25 Figure 4.3 Environment 20 - 40 Lowland Raised Bog Extent and Areas Agency Region 26 - 50 40 - 60 at Risk Under Scenario 2100 Medium with Degraded Defences in 1 in 1,000 Lowland Raised Bog 51 - 100 60 - 80 year tidal and tidal/fluvial flood zone 2 1 in 1,000 year tidal and 100+ 80 - 100 in Northern England tidal/fluvial flood zone 2 0 50 G:\MODEL\PROJECTS\EA-210\24903 Coastal Biodiversity March 2011 Km 24903-S17c stokr and Climate Change\ArcGIS\Figures\24903-S17c_LRB_Risk.mxd Scale: 1:1,750,000 @ A4

Based upon the Ordnance Survey Map with the permission of the Controller of Her Majesty's Stationery Office. © Crown Copyright. AL100001776 400000 500000 600000 100000 100000

Deciduous Woodland in 1 in 1,000 year tidal and tidal/fluvial flood zone 2

400000 500000 600000 100000 100000

Deciduous Woodland Area at Risk (ha) in 1 in 1,000 year tidal and tidal/fluvial flood zone 2

400000 500000 600000

Note: This is a snapshot of Deciduous Woodland habitat at risk, focussed on the Environment Agency Southern Region

Area and percentages of habitat at risk presented are per 5km square grid cell. 100000 100000 Deciduous Woodland Percentage Area at Risk in 1 in 1,000 year tidal and tidal/fluvial flood zone 2

400000 500000 600000 Key Area of Deciduous Percentage Area of Coastal Zone Adaptation Woodland at Risk (ha) Deciduous Woodland to Climate Change Deciduous Woodland in at Risk 1,000 year tidal and tidal/ 1 - 10 Figure 4.4 fluvial flood zone 2 1 - 20 Deciduous Woodland 11 - 25 Environment 20 - 40 Extent and Areas at Risk Under Agency Region 26 - 50 40 - 60 Scenario 2100 Medium with Degraded Deciduous Woodland Defences in 1 in 1,000 year tidal and 51 - 100 60 - 80 tidal/fluvial flood zone 2 in Environment 1 in 1,000 year tidal and Agency Southern Region tidal/ fluvial flood zone 2 100+ 80 - 100 0 50 G:\MODEL\PROJECTS\EA-210\24903 Coastal Biodiversity March 2011 Km 24903-S18c stokr and Climate Change\ArcGIS\Figures\24903-S18c_DecWood_Risk.mxd Scale: 1:1,750,000 @ A4

Based upon the Ordnance Survey Map with the permission of the Controller of Her Majesty's Stationery Office. © Crown Copyright. AL100001776

5. Implications for BAP habitats in England

This section considers the projected losses of the selected BAP habitats under the range of climate change scenarios in the context of the national resource, and then discusses the implications of the projected losses for meeting legal and conservation policy drivers in England and the potential costs associated with these.

5.1 Projected habitat losses - overview of impacts

Of the 109,020 ha (1,090 km2) of habitat present in the coastal floodplain, 81% of the total selected BAP habitats at risk under any scenario are at risk under climatic conditions prevailing currently and hence could be lost to flood events at any time in the next 10 to 20 years. This is a clear indication that action is needed now to commence establishment of habitat that could be lost. Such an initiative would be in accordance with the overriding principle, to Act Now, advocated by Smithers et al. (2008) in ‘England Biodiversity Strategy Climate Change Adaptation Principles: Conserving biodiversity in a changing climate’.

A sample of the projected losses by scenario for selected BAP habitats in the coastal floodplain is presented in Table 5.1. This illustrates that coastal and floodplain grazing marsh comprises the majority (84%) of the selected priority BAP habitats in the coastal floodplain and also that around 88% of the habitat at risk of loss under the climate change scenarios comprises coastal and floodplain grazing marsh. Coastal and floodplain grazing marsh was ranked the fifth most difficult habitat to create in Section 2.3.2 which, when combined with the areas involved, suggests that significant time and funding will be required to create replacement habitat. It is also notable that average losses of lowland raised bog are projected to be the fourth highest of all the selected habitats included in the study and lowland raised bog was assessed as being the most difficult habitat to create; indeed, it is almost twice as difficult on the basis of the scoring criteria used as the next most difficult (lowland fen). The difficulty in creating lowland raised bog perhaps suggests that consideration should be given to special protection for this habitat type.

The figures presented in this study are projections of possible habitat losses under a range of climate change scenarios. However, it is important to note that there will be areas of habitat that would be degraded by the same flood events that result in habitat losses. This degraded area is not quantified in this study, but could be considerable. It should not be ignored as this degradation would be likely to affect the quality and functionality of

some of the remaining BAP habitat and take time to recover from. Hence, the projected losses would be compounded, potentially for some years, by the quality of remaining BAP habitat having been temporarily compromised by exposure to flood events.

Table 5.1 Extents of all selected BAP habitats within the coastal floodplain at risk of loss (sample of modelled scenarios)

Total Current Projected additional risk to all selected BAP habitats resulting from Habitat risk (Ha) climate change scenarios (Ha) Habitat (Ha) in coastal floodplain 2010 2030MM 2060MM 2100MM 2030MD 2060MD 2100MD

CFPGM Grassland 87,581 3,919 340 421 477 526 715 823

CFPGM Ditches 3,649 127 3 14 17 22 25 30

D. Wood 5,768 191 6 27 39 38 42 56

LRB 2,898 106 25 41 41 80 95 96

Reed (habitat) 2,564 39 5 9 12 10 10 12

Reed (species) 2,564 103 9 18 23 21 20 25

Fens 1,964 29 1 1 1 5 5 5

Ponds 1,889 60 5 9 11 14 14 18

Lakes 1,511 33 4 3 4 5 5 7

SL 1,112 0 0 0 0 0 0 0

PMGRP 85 3 0 1 1 0 1 1

Totals 109,020 4,571 393 537 614 711 923 1,060

Habitat codes: LRB – Lowland raised bog, CFPGM – Coastal and floodplain grazing marsh, SL – Saline lagoons, Reed (habitat) – reedbed habitat only, Reed (species) – reedbed taking faunal species interest into account, PMGRP – Purple moor grass and rush pasture, D. wood – Deciduous woodland.

Scenario references are year, UKCP09 emission scenario (L = low, M = medium, H = high), defence status (M = maintained, D = degraded).

5.2 Legal and conservation policy drivers

There is a range of legal and Government policy drivers for the restoration and creation of habitats that are increasingly vulnerable at the coast. The main drivers are the Habitats and Birds Directives which place a legal obligation on competent authorities - operating in certain circumstances - to replace freshwater, brackish and saline habitat lost at the coast within Natura 2000 sites (SAC, SPA) as a consequence of sea-level rise. The competent authorities, in exercising any of their functions, must have regard to the requirements of the Habitats Directive insofar as sites may be affected by the exercise of those functions12. This includes taking appropriate steps to

12 Regulation 9(5) of the Habitats and Species Regulations 2010.

avoid, in European sites, the deterioration of natural habitats and the habitats of species. This is as well as disturbance of the species for which the areas have been designated insofar as such disturbance could be significant in relation to the objectives of the Habitats Directive13. The need to replace or compensate for lost freshwater habitat would normally arise as a result of plans or projects involving coastal realignment. Flood and Coastal Risk Management operating authorities are responsible for replacing habitat lost at the coast within Natura 2000 sites as a result of flood and coastal risk management plans and projects. The Environment Agency does this through their Regional Habitat Creation Programmes. The Water Framework Directive also places responsibility on Member States to implement the necessary measures to prevent deterioration of the status of all waterbodies, and protect, enhance and restore all waterbodies. In addition, it is a current Defra business plan priority to “enhance and protect the natural environment, including biodiversity and the marine environment, by ... preventing habitat loss and degradation.” Finally the England Biodiversity Strategy (Defra, 2002) includes the objective for ‘Water and Wetlands’ to ‘Progress towards water and wetland HAP/SAP targets in England (including the contribution of high level flood management targets) (W1)’. This objective contributes to the delivery of the current 2010-2020 BAP targets, as reported on the Biodiversity Action Reporting System (http://ukbap-reporting.org.uk), which derive from the UK BAP, which in general require ‘no net loss’ of BAP habitats but in a number of cases require the restoration of relict, or creation of new, habitats.

5.2.1 Implications of the projected losses for European sites

It is projected that an average of 1,467 ha of the selected BAP habitats are at risk within SAC/SPA and Ramsar sites combined under climate conditions prevailing currently. This increases by 8% by 2030, 19% by 2060 and 22% by 2100 under the medium emission, defences maintained scenarios. These projected habitat losses are important for two reasons. First, the losses are from within Natura 2000 sites and therefore are likely to be high- quality examples of the BAP habitat types. Second, there is a legal obligation to replace these habitat areas if they are lost. Commencing habitat creation before the projected losses occur would help to ensure that there is no net loss of BAP habitat resource going forward.

In addition, sites have often been designated as SACs or SPAs because of the presence of particular species. Thus, the conservation status of such sites will be reliant on the status of the individual species as well as the habitats present. This study has focussed on habitats and therefore may be under-predicting the effects of sea-level rise on the Natura 2000 network as species requirements are not specifically covered. An example of the difference that the inclusion of species requirements makes to the projections is illustrated by the projections of losses for reedbeds, for which two sensitivity matrices were defined and run in the NaFRA model. There is a significant difference between results for the habitat-only matrix compared to the matrix also taking account of species requirements. Clearly the difference would depend on the habitat and species being considered, but the implications of sea-level rise for species of conservation interest within coastal designated sites merits further consideration.

13 Article 6(2) Council Directive 92/43/EEC of 21May 1992 on the conservation of natural habitats and of wild fauna and flora.

5.2.2 Implications of the projected losses for meeting BAP targets

Progress towards BAP targets

The 2010-2020 BAP habitat targets and progress towards achieving them, are presented on the Biodiversity Action Reporting System (http://ukbap-reporting.org.uk). The 2008 reporting suggested that good progress was being made towards meeting a number of the 2010 BAP targets requiring creation of BAP habitats. However, it has proved difficult to interpret progress towards BAP targets for a number of reasons:

• The reported progress contains acknowledged over-estimates (coastal and floodplain grazing marsh);

• For some habitats there is uncertainty about current extent and hence targets may have been incorrectly defined (saline lagoons);

• It is unclear whether all the figures represent functional habitats at the time of the 2008 reporting or whether they have just been established and hence have some years to go until they can be considered functional BAP habitats;

• The quality of the habitats created is unknown and it is unclear whether the habitats included in the progress figures are good examples of BAP habitats or poor examples, or somewhere in between.

A more detailed examination of the difficulties in interpreting the BAP targets and progress towards them is provided by the example below of coastal and floodplain grazing marsh, supplied by Natural England.

Coastal and Floodplain Grazing Marsh

There are four relevant BAP targets for coastal and floodplain grazing marsh:

• T1 - Maintain the extent of the existing resource of coastal and floodplain grazing marsh habitat with no net loss. (In particular, ensure that grazing marsh of similar quality is created to landward of flood defences that have been abandoned or breached as sea level rises, by mapping where compensatory habitat will be created in Shoreline Management Plans and other plans set out by statutory agencies);

• T2 - Maintain the condition of coastal and floodplain grazing marsh habitat where already favourable and establish, by 2010, management to secure favourable condition for all areas of grazing marsh currently judged as unfavourable. The target condition for all such areas should be favourable or unfavourable recovering by 2020;

• T3 - Restore and improve 25,000 ha of relict habitat that does not qualify as coastal and floodplain grazing marsh habitat by 2020. (e.g. dry coastal and floodplain grazing marsh with inappropriate hydrological regime, agriculturally improved sites, etc., by implementing appropriate management at all sites);

• T4 - Re-establish 3,200 ha of C&FPGM of wildlife value from appropriate land sources (e.g. arable land) by 2020 (which is capable of supporting a diverse range of invertebrates, mammals and breeding waders).

The numerical targets associated with T1-T4 are presented in Appendix M.

Definition of coastal and floodplain grazing marsh The definition of coastal and floodplain grazing marsh was modified at the last review of BAP targets in 2006. The major change from the previous definition was the requirement for high in-field water levels and the presence of vegetation or species of high value.

Extent The England area of coastal and floodplain grazing marsh is estimated to be 170,000 ha. The current estimate of 170,000 ha is not now believed to be an accurate representation of the area of coastal and floodplain grazing marsh with high water levels and/or biodiversity interest, and therefore is not an accurate representation of the extent of existing coastal and floodplain grazing marsh as defined by the new HAP description. Earlier estimates of grazing marsh of high biological value were in the region of 30,000 ha (Mountford et al., 1999). This has implications for the targets presented above, and the way these are dealt with in this report.

Of this total extent, 87,581 ha is in the coastal floodplain. This study identifies 30,279 ha of grazing marsh SSSI in the coastal floodplain. The total area of coastal and floodplain grazing marsh in SSSIs is 37,288 ha (Natural England, 2008), so 81% of all coastal and floodplain grazing marsh in SSSIs is in the coastal plain.

Targets Probably the key target identified above is the T2 target which requires 153,000 ha of existing coastal and floodplain grazing marsh to be brought into ‘favourable condition’ by 2020 (see Appendix M). This assumes that this area of habitat is already recognisable as coastal and floodplain grazing marsh (i.e. wet and/or biologically rich), which is not now believed to be the case (Natural England, pers. comm.). Limited evidence suggests that over half this figure does not qualify as coastal and floodplain grazing marsh, and enhancement of this degraded ex- coastal and floodplain grazing marsh would therefore require ‘Restoration’ (contributing to T3) rather than ‘Rehabilitation’ (contributing to T2). Progress towards target T2 in 2008 was somewhat behind schedule - a total of 29,792 ha was recorded as Favourable or Unfavourable Recovering, on the basis of SSSI condition and uptake of the highest tiers of HLS.

The 2006 target T3 requires 15,000 ha of ex- coastal and floodplain grazing marsh (land that does not currently meet the new definition) to be restored in England by 2020. In 2008 24,987 ha was reported as ‘under restoration’ through a combination of agri-environment schemes and action by the RSPB. Recent site assessments of a sample of coastal and floodplain grazing marsh counting towards this target suggests that fewer than half of the sites are sufficiently wet and/or supporting high value wildlife habitat, and therefore do not yet meet the habitat definition.

The combined T2 and T3 progress is 54,759 ha (with previous caveats about habitat quality). There is still therefore a requirement to restore and/or rehabilitate 115,241 ha of 170,000 of potential coastal and floodplain

grazing marsh by 2020. As discussed above, evidence suggests that the majority of this remaining ‘coastal and floodplain grazing marsh’ does not meet the new definition of the habitat, and so would fall into the T3 ‘restore’ target, rather than T2 ‘rehabilitate’ target.

As a result of the uncertainties identified above, significant caution is required in interpretation of the implications of the habitat losses projected by this study in the context of the progress towards BAP targets. As a result this report does not attempt to do this. However, it would be prudent to add the average extents of habitat at risk of loss to the current creation/rehabilitation targets with the aim of ensuring that losses that could occur due to sea-level rise are taken into account in meeting BAP targets (i.e. policies on preventing loss or degradation of BAP habitat, and creation/rehabilitation targets).

Assessment of extent of habitat creation that may be needed

The modelling projections can be viewed as the average amount of habitat that may be needed to replace habitat that is at risk of loss due to flooding from sea-level rise. As indicated in Section 3, actual losses over a year or a decade may be higher or lower, depending on whether a coastal flood event happens and how extreme the event is. The average loss figure takes into account this range of possible outcomes and represents, on average, the amount of habitat that should be created in order to compensate for the losses that could be experienced under the different scenarios during the coming century.

The modelling suggests that nationally an average total of 4,571 ha of lowland open-water and wetland priority BAP habitats are at risk of loss as a result of tidal inundation events under current climate conditions. This total increases to an average of 4,964 under the 2030 medium with defences maintained scenario, 5,108 ha under the 2060 medium with defences maintained scenario and 5,631 ha under the 2100 medium with degraded defences scenario (see Table 4.1).

If habitat was to be replaced in the regions in which it is predicted to be at risk of loss, then the focus for habitat creation will be in the Environment Agency’s South-West and Anglian Regions because 36% of the habitat at risk of loss under both current and future climate conditions (2100 medium with degraded defences scenario) is from these regions14.

It is more desirable to re-create habitats within coastal floodplain areas as these habitats are not found, or are different in nature, within non-floodplain areas. Whilst re-creation in the coastal floodplain will mean that this habitat may still be exposed to flooding, albeit with reduced risk of loss, this may remain the most practical approach to climate change adaptation. Action to maintain the overall national resource, even if located in the coastal floodplain, will mean that if further loss from flooding occurs in one region, there will remain a greater buffer on the overall resource with resources elsewhere.

14 It should be noted that it is not the Environment Agency’s responsibility to replace all this habitat – the report is referring to the Agency regions for ease of description.

Habitat replacement outside of the coastal floodplain would result in a reduction in the extent of some types of BAP habitat in coastal areas, and in the replacement of habitats with a coastal character (species compositions and environmental characteristics) by habitats with a more inland character. This quandary over where restoration effort should be targeted echoes the discussion by Mountford et al. (1999). Further work is needed to consider the practical opportunities and constraints for habitat recreation within the coastal floodplain.

Timescales for habitat creation

The model-derived areas of habitat at risk of loss are small compared to the total habitat resource present within the coastal floodplain (up to 7% at most) and also, in most cases, to the current BAP habitat creation and rehabilitation targets. Nonetheless, it will take time to create 4,571 ha (45.7 km2) of habitat that are at risk of loss under the current (2010) climatic conditions and longer still to create the amounts that could be lost under the 2030, 2060 and 2100 scenarios. As the majority of the habitat at risk of loss is at risk under current climate conditions, this reinforces the comments of Smithers et al. (2008) on the need to act immediately in order to adapt to the impacts of climate change.

Much could be achieved potentially within a relatively short period of time to offset future losses as around 90% of the habitat area at risk of loss under the modelled scenarios can establish over a 5 to 9-year time period (see Table H.2 in Appendix H). However, it will take a significant period of time to identify appropriate sites for re- creation, reach agreement with landowners and obtain funding for the work and therefore the actual period that will be required is very difficult to predict and is not a function of the ease of habitat creation determined in Section 2.3. It must also be noted that the remaining 10% of the habitat area that would need to be created (e.g. 561 ha if the 2100 medium with degraded defences scenario occurred) would be expected to take between 10 to 100 years to establish. Furthermore, lowland raised bog, which comprises nearly 40% of the 561 ha mentioned, will take from 50 years upwards.

Whilst there are several on-going habitat creation initiatives around the country that may contribute to meeting this need, they will do this over a long time period of at least several decades. Importantly, they are not all in coastal locations.

Costs of habitat creation

An indication of the cost of replacing habitat areas at risk of loss is provided below in Table 5.4. The costs have been calculated using the cost per hectare for replacement derived by the NEOCOMER study (Defra, 2006). As stated previously, the extents at risk reported in this study are the average habitat losses that could be experienced under each climate change scenario.

The analysis suggest that, using the 2007 cost per hectare from the NEOCOMER study (which included land purchase costs at 2004 values), it would cost around £88 million to replace the average habitat extent at risk under current climate conditions, whilst it would cost £109 million to replace the average habitat extent at risk under the 2100 medium with degraded defences scenario. However, it is important that caution is exercised in interpreting

the monetary values quoted because, as indicated previously, outputs represent the average loss that could be experienced under each climate change scenario. Actual losses over a year or a decade may be higher or lower, depending on whether a coastal flood event happens, how extreme the event is and the level at which coastal defences are maintained. Nonetheless, the figures calculated are considered significant as they are in addition to the funds needed specifically to meet BAP targets and replace habitat that will be lost as a result of processes not taken account of in this project, including:

• Replacement of coastal habitat in Natura 2000 sites that will be lost as a result of coastal erosion and related loss of lowland wetland BAP habitats;

• Coastal re-alignment programmes to address ‘coastal squeeze’ of inter-tidal habitats or where current sea defences are deemed uneconomic in situ.

Table 5.4 Estimated costs of replacing habitat at risk of loss

Habitat Extent at risk Additional Cost per Cost of Additional cost Estimate total under current extent at risk hectare (£)1 replacement of replacement cost for climate under (source: for losses for losses replacement scenario 2100MD NEOCOMER) under current under 2100MD for 2100MD scenario climate (000s) (000s) (000s)

CFPGM Grass and 4,046 853 15,174 61,394 12,943 74,337 ditch

Lowland Raised 106 96 14,424 1,528 1,384 2,913 Bog

Deciduous Wood 191 56 9,674 1,847 541 2,389 (wet wood)

Reed (Species) 103 25 14,4243 14,857 3,606 18,463

Ponds4 60 18 23,174 1,390 417 1,808

Reed (No Species) 39 12 14,4243 5,625 1731 7,355

Lakes 33 7 23,174 764 162 927

Fens 29 5 14,424 418 72 490

PMGRP 3 1 14,4243 433 144 577

Saline Lagoons 0 0 23,1742 0 0 0

Totals (excludes 4,571 1,060 - 88,259 21,002 109,262 reed no species)

1 The cost per hectare includes average land purchase costs at 2004 values. 2 Not stated in NEOCOMER so used the inland waterbodies and lagoons figure. 3 Not stated in NEOCOMER so used the bogs, marshes, fens figure. 4 Total pond extent is presented, not priority ponds. It is estimated that around 20% of ponds nationally will be priority ponds. However, this percentage rises when ponds are located in designated sites.

The analysis of cost of creating replacement habitats against the benefits, for example in respect of the ecosystem services that these habitat provide, is beyond the scope of this study.

6. Conclusions and Suggestions

6.1 Conclusions

There are a number of features of this project that make it different from previous studies (see Section 1). Probably the most important is that this is the first time that a probabilistic approach has been taken to assess the potential loss of habitat as a result of climate change and sea-level rise. All other studies have been deterministic. A probabilistic approach has been used before to assess the risk of property damages from flooding but not losses in the natural environment. Additionally, other studies have assumed that all exposure to saline inundation will result in habitat loss. In this project, the sensitivity of the habitats to saline inundation events has been factored into the analyses.

Overall, the project’s innovative approach to assessing the risk of BAP habitat loss to sea-level rise has produced results that, while indicating lower than anticipated losses, are believed to be more realistic than previous studies.

Over half of the national resource of coastal and floodplain grazing marsh, reedbed and saline lagoons, and over 30% of lowland raised bog in the derived alternative habitat inventories are situated in the coastal floodplain. This illustrates the importance of this coastal zone in maintaining the national resource of these habitats. It is also worthy of note that the composition of BAP habitat in coastal areas will be influenced by the coastal environment and hence will often be different from those located in more inland locations. Therefore, although the extent of a number of the other selected BAP habitats located in the coastal situations is relatively small in terms of their percentage of the national resource, the fact that habitats with a particular coastal character comprise a relatively small amount of the national resource places additional value on these, thus reinforcing the importance of the coastal zone in supporting these priority BAP habitat types. Projected losses due to climate change are therefore likely to be considered significant in the context of both maintaining the national resource of certain habitats and also with respect to maintaining the extent of the coastal variations of these habitats.

An average of 4,571 ha (45.7 km2 - 4.2%) of the selected BAP habitats are at risk of loss under climatic conditions prevailing currently (2010) and this increases 23% under the highest projection, 2100 medium with degraded defences, to an average of 5,631 ha (56 km2) which is 5.1% of the total habitat resource. Whilst there is some uncertainty over the quality of the habitats that may be lost where they occur outside designated sites, over 30% of the projected losses occur within SSSI, SAC, SPA and Ramsar sites. It is expected that in these cases the habitats that will be lost will be good examples of their type.

A key message is that the majority of the risk of loss pertains under current climatic conditions and could occur at any time in the next 10-20 years. This is a clear indication that action is needed now to commence establishment of habitat that could be lost and this is also the overriding principle that is advocated by Smithers et al. (2008) in ‘England Biodiversity Strategy Climate Change Adaptation Principles: Conserving biodiversity in a changing climate’.

The need for immediate action is reinforced when account is taken of the timescales needed for creating good quality examples of the selected BAP habitats, and also for locating practical habitat creation opportunities. Additionally, significant funds will be needed to create habitat areas of the extent projected to be at risk of loss.

It is important that uncertainty is clearly acknowledged in a project such as this. Headline uncertainties associated with the project were outlined in Section 1.5 and are reproduced here:

• The spatial distribution of lowland open-water and wetland priority BAP habitats;

• The sensitivity of these BAP habitats to inundation from the sea;

• The effects of climate change on sea levels in the future;

• The difficulty in predicting how, where and how often flood events may take place, and the consequences for flood extent and related habitat loss;

• The ability to artificially create BAP habitats.

Information on uncertainty and limitations has been provided at appropriate points throughout the report along with, where applicable, an explanation of how this has been managed, such as the derivation of project-specific habitat inventories. A number of important assumptions were also made, in particular when the sensitivity matrices were being populated, and these are reproduced below:

• Flushing with freshwater is a key feature supporting habitats on many sites in coastal areas and will significantly influence the impacts of any inundation with brackish/saline water. The NaFRA model cannot predict the presence and effects of flushing with freshwater. However, it is considered that the matrices derived implicitly consider the effects of flushing because, as far as possible, they are based on observations from sites that experience flushing;

• Effects of rising sea level resulting in backing up of freshwater and increasing freshwater flooding are not considered.

It is also important to note that the modelling undertaken for the project did not take account of losses of habitat that may occur as a result managed re-alignment projects or coastal erosion, both of which could add to the projected losses.

Notwithstanding these issues, it is felt that the project provides an important first indication of the extent of BAP habitat that may be lost in the coastal floodplain as a result of climate change and of the potential difficulties in replacing these habitats. Consequently, it should assist strategic decision-making on the fate of precious and vulnerable BAP habitats.

6.2 Suggestions

A number of suggestions arise from the work undertaken for this study:

• The magnitude of projected losses under climate conditions prevailing currently (2010) suggests that there should be an immediate programme of habitat creation to begin to address the risk of habitat losses;

• Regardless of the need to clarify formal BAP targets, projected extents of BAP habitat at risk of loss derived during the study suggest that 4,571 ha of habitat is at risk under current climate conditions, increasing to 5,631 under the 2100 medium with degraded defences scenario. Therefore, it is suggested that a specific programme be established to consider tackling the potential habitat replacement needed for SSSI, SAC, SPA and Ramsar sites;

• The current study did not consider in detail the implications for species. This may be particularly important in respect of Natura 2000 sites where conservation status may be reliant on the status of individual species as well as habitats. Further consideration is recommended of the impacts of sea- level rise on species of conservation interest;

• The focus of this study was on lowland open-water and wetland BAP habitats. However, this ignores the extent of other lowland terrestrial BAP habitats that occur in coastal areas, such as lowland heathland. Whilst this study did consider ‘deciduous woodland’ in assessing the risk to BAP habitats, this was only because of the absence of a reliable habitat dataset for wet woodland. Therefore, it is suggested that these other habitats be taken into account in similar future studies. To do this, sensitivity matrices and habitat mapping will be required for the other habitats to be included;

• Clarification of the definitions of the BAP habitats is required if possible. More precise definitions would hopefully reduce the potential for overlaps in habitat inventories;

• Clarification of the national BAP targets and current progress towards achieving them is urgently required. There are significant uncertainties around the measurement of the present resource, the quality of the habitats currently being restored or created, and thus the status of the national targets. It should be noted however that the targets are currently under review as part of the review of the England Biodiversity Strategy and the targets may change as a result of this review;

• Clarification is urgently required of the implications of the projected habitat losses for national BAP targets. Clearly, the current national framework of BAP habitat targets, and any future revision of this through the review of the England Biodiversity Strategy, needs to take account of the projected habitat losses identified by this project;

• This report does not include projections of what habitats will develop in areas where freshwater open water and lowland wetland BAP habitats are lost (for example coastal and floodplain grazing marsh changing to saltmarsh). A future study should include consideration of this;

• The existing nationally-available BAP habitat mapping proved unusable for this project due to overlaps and inaccuracies. As a result, project-specific habitat inventory datasets were derived. Although still uncertain, they were perceived to be better that the nationally-available data. Additionally, it is believed that all currently-available datasets, apart from coastal and floodplain grazing marsh, under-estimate the extent of BAP habitats outside designated sites. Thus, significantly improved mapping of BAP habitats is needed both within and outside designated sites. Not only will this mean that there can be greater confidence in the BAP habitat resource figures quoted nationally, but it will also enable this, and other similar future studies, to use a common baseline dataset allowing greater confidence when comparing results of analyses. At the time of publication the revised regional inventories referred to in the report are about to be incorporated into the national datasets by Natural England and the project-derived habitat inventories should be compared with, and if considered appropriate following the comparison replaced by, these in any future similar project. Ponds and lakes inventories are not included in the Natural England review however;

• There is clearly a gap in scientific knowledge on the sensitivity of lowland open-water and wetland habitats to coastal (saline) inundation. Because of predicted sea-level changes and the increased likelihood of inundation of habitats behind the natural and defended coastline, greater research effort is required to better understand the sensitivities of these habitats to saline inundation;

• The modelling undertaken for the project did not take account of losses of open water and lowland wetland habitat that may occur as a result managed re-alignment projects or coastal erosion, both of which could add to the projected losses. It may be possible to build the effects of coastal erosion into future modelling but managed re-alignment is a project specific activity and modelling cannot take this into account unless the model is told when and where to include that activity;

• The project results can be updated as more or better data become available. In addition to using updated habitat mapping and sensitivity matrices as they are developed, updates may also be undertaken for new releases of NaFRA or updated projections of sea-level rise. Updating of the project outputs would involve re-running the modelling with the new version of the data for any of these data inputs, starting at the appropriate step in the modelling process (see Box 3.1 giving a flow chart of steps);

• The costs presented for creation of replacement habitat areas were defined on the basis of 2007 data on costs per hectare. This may underestimate the cost of habitat creation and should, if possible, be revisited with updated information;

• In light of the results of this study, it is believed that there is a need for a national strategy and linked programme of delivery to plan and co-ordinate habitat creation activities to address projected losses;

• The results of this study should be incorporated into the Defra National Ecosystem Assessment and Climate Change Risk Assessment projects and the findings are also relevant to the proposed Natural Environment White Paper.

7. References

Bamber, R.N., Gililand, P.M. and Shardlow, M.E.A. (2001). Saline lagoons – A Guide to their Management and Creation. English Nature.

Benstead, P., Drake, M., José, P., Mountford, O., Newbold, C. and Treweek, J. (1997). Wet Grassland Guide. Managing floodplain and coastal wet grasslands for wildlife. RSPB.

Binnie and Partners (1992). A Flood Alleviation Strategy for Broadland – Washland Development. Background Technical Papers.

Defra (2006). National evaluation of the costs of meeting coastal environmental requirements. R&D Technical Report FD2017/TR. Produced: April 2006. Authors: Risk & Policy Analysts Ltd, Royal Haskoning UK Ltd, ABP Marine Environmental Research Ltd.

Drake, C.M, Stewart, N.F., Palmer, M.A. & Kindemba, V. L. (2010) The ecological status of ditch systems: an investigation into the current status of the aquatic invertebrate and plant communities of grazing marsh ditch systems in England and Wales. Technical Report. Buglife – The Invertebrate Conservation Trust, Peterborough.

EC Life Project – Living with the Sea (http://www.eclife.naturalengland.org.uk/).

Ecoscope (2000). Wildlife Management and Habitat Creation on Landfill Sites. A manual of best practice. Ecoscope Applied Ecologists. Muker.

George, M. (1996). The Aquatic Flora of the RSPBs Cantley Dyke System. Report for RSPB.

Gilbert, O.L. and Anderson, P. (1998). Habitat Creation and Repair. Oxford University Press.

Gouldby, B., Sayers, P, Mulet-Marti, J., Hassan, M., Benwell, D. (2008) A methodology for regional-scale flood risk assessment. Proceedings of the Institute of Civil Engineers. WM0. doi 10.1680/wama.2008.000.0.1

Gouldby, B., Sayers, P., Mulet-Marti, J., Hassan, M., Benwell, D. (2008). A methodology for regional-scale flood risk assessment. Water Management. Issue WM0 pp1-14.

Hawke, C J and José, P V. (1996). Reedbed management for commercial and wildlife interests. Sandy: Royal Society for the Protection of Birds.

Hill, M.O., Preston, C.D. and Roy, D.B. (2004). PLANTATT: Attributes of British and Irish Plants: Status, Size, Life History, Geography and Habitats. Huntingdon: NERC Centre for Ecology and Hydrology.

HR Wallingford. (2011). Outline of methodology for assessing loss of coastal Biodiversity Action Plan habitat due to sea level rise. Technical Note MCR4496-01. Complimentary output of Defra project CR0422.

Lhomme, J., Sayers, P., Gouldby, B., Samuels, P., Wills, M., Mulet-Marti, J. (2009). Recent development and application of a rapid flood spreading method. In Samuels P., Huntington S., Allsop W. and Harrop J. (eds), Proceedings of the FloodRisk 2008 Conference, Taylor and Francis Group, London.

Mountford, J.O., Cooper, J.M., Roy, D.B. and Warman, E.A. (1999). Targeting areas for the restoration and re-creation of coastal and floodplain grazing marsh. English Nature Research Report no. 332. Peterborough: English Nature.

Mountford, J.O., Rose, R.J. and Bromley, J. (2005). Development of eco-hydrological guidelines for wet heaths - Phase 1. English Nature Research Report no. 620. Peterborough: English Nature. ISSN 0967-876X.

Natural England (2008). State of the Natural Environment. Natural England. Sheffield.

Palmer, M., Drake, M. & Stewart, N. (2010) A Manual for the Survey and Evaluation of the Aquatic Plant and Invertebrate Assemblages of Grazing Marsh. Ditch Systems. . Buglife – The Invertebrate Conservation Trust, Peterborough.

Palmer, M. & Kindemba, V. (2010). The ecological status of ditch systems. Buglife – The Invertebrate Conservation Trust, Peterborough.

Parker, D.M. (1995). Habitat Creation – A Critical Guide. English Nature.

Perrow, M.R, and Davy, A.J. (2002). Handbook of Ecological Restoration. Cambridge University Press.

RPA (2006). Flood Defence Standards for Designated Sites. English Nature Research Report No. 629. English Nature.

Sainty, J.E. (1939). Past History of Sea Flooding and Cause of the 1938 Flood. Transactions of the Norfolk and Norwich Naturalists Society, 14, 334-335.

Smithers, R.J, Cowan, C., Harley, M., Hopkins, J.J., Pontier, H. and Watts, O. (2008). England Biodiversity Strategy Climate Change Adaptation Principles: Conserving biodiversity in a changing climate. Report for Defra.

Sutherland, W.J. and Hill, D.A. (1995). Managing Habitats for Conservation. Cambridge University Press.

Symes, N.C. and Robertson, P.A. (2004). A Practical Guide to the Management of Saline Lagoons. The RSPB. Sandy.

Wheeler, B.D., Gowing, D.J.G., Shaw, S.C., Mountford, J.O. and Money, R.P. (2004). Ecohydrological Guidelines for Lowland Wetland Plant Communities. Eds Brooks, A.W., José, P.V. and Whiteman, M.I. Peterborough: Environment Agency (Anglian Region).

Wheeler, B.D. and Shaw, S.C. (2000). A Wetland Framework for Impact Assessment at Statutory Sites in Eastern England. Environment Agency R&D Note. W6-068/TR1 and TR2.

Appendix A Project Brief

Competition Details and Project Specification

Competition Code: CR0422 Date for return of tenders: 5th February 2009

Address for tender submission: Competition Code: WC0726 (the Competition Code must be shown on the Mark Pearce envelope and the tender submitted in line Defra with the instructions in the attached guidance, otherwise your tender may not be Natural Resources and Rural Affairs accepted) Zone 1/06b Temple Quay House 2 The Square Temple Quay Bristol BS1 6EB Number of electronic & hard 1 copy on CD-ROM or 3½” disk, plus copies required: 4 hard copies Contact for information relating to Helen Pontier this project specification: [email protected] 0117 3728705

Proposed ownership of Intellectual Contractor Property (contractor or Defra): Proposed start-date (if known): February 2009

Proposed end-date (if known): March 2010

SPECIFICATION OF REQUIREMENTS

Developing tools to evaluate the consequences for biodiversity of options for coastal zone adaptation to climate change

SUMMARY STATEMENT OF REQUIREMENT The aims of this project are to achieve a strategic national (England) overview of the extent of habitat at the coast that may be lost over the next 100 years due to the effects of climate change and sea-level rise, so locations that offer opportunities for sustainable, large-scale re-creation of these habitats elsewhere at the coast or inland can be identified in phase 2.

BACKGROUND Climate change is now widely recognised as one of the major drivers of global biodiversity change and loss. Climate change is predicted to result in sea-level rise and increased frequency of extreme events, such as storms and flooding. Policy adaptations include the need to consider appropriate flood risk management responses, but also to anticipate the effects on habitats at the coast, including freshwater, brackish and saline habitats behind the current natural and defended coastline. They also need to consider application of existing climate projection guidance, such as the UKCIP 08 scenarios1, and biodiversity management guidance, such as the England Biodiversity Climate Change Workstream Adaptation Principles, protected site guidance2 and recently published literature reviews3. Strategies need to be designed and implemented in a timely way so as to facilitate adaptation at the coast and, where constraints on adaptation result in habitat losses, to maximise the opportunities for habitat re-creation inland.

There are a number of legal and Government policy drivers for the restoration and re-creation of habitats that are increasingly vulnerable at the coast:

• Targets for 2020 agreed under the UK Biodiversity Action Plan (UK BAP) are to: o restore 25,000 hectares of relict grazing marsh; o initiate the restoration of 2,800 hectares of former fen; o create 3,200 hectares of new grazing marsh; o create 3,000 hectares of reedbed; o In addition, there is a commitment to establish 8 new landscape-scale wetland complexes. • Separate to this is the need to replace freshwater, brackish and saline habitat lost at the coast as a consequence of sea-level rise. There is a statutory requirement to do this where damaging impacts to Natura 2000 sites arise as

1 http://www.ukcip.org.uk/index.php 2 Hopkins, J.J.; Allison, H.M.; Walmsley, C.A.; Gaywood, M.; Thurgate, G. (2007) Conserving Biodiversity in a changing climate - Building capacity to adapt, Defra, available at: http://www.ukbap.org.uk/Library/BRIG/CBCCGuidance.pdf 3 Mitchell, R.J.; Morecroft, M.D.; Acreman, M; Crick H.Q.P.; Frost, M. ;Harley, M.; Maclean, I.M.D.; Mountford, O.; Piper, J.; Pontier, H.; Rehfisch, M.M.; Ross, L.C.; Smithers, R. J;, Stott, A.; Walmsley, C.; Watts, O.; Wilson, E. (2007) England Biodiversity Strategy: Towards Adaptation to Climate Change. Available at http://randd.defra.gov.uk/Default.aspx?Menu=Menu&Module=More&Location=None&ProjectID=1 3807&FromSearch=Y&Publisher=1&SearchText=towards%20adaptation&SortString=ProjectCode &SortOrder=Asc&Paging=10#Description

2 a result of decisions to realign or not to maintain sea defences which are currently protecting such sites. In addition, the UK BAP targets will require additional habitat to be re-created to replace that lost at the coast. • The joint Wetland Vision (www.wetlandvision.org.uk) has identified the need for more ambitious habitat creation targets for England to be set over a 50- year timescale; for example, a doubling of the area of reedbed to achieve sustainable populations of certain wetland species.

Some work , ( eg BRANCH4, ReGIS5) has already been done to identify the extent and timing of the habitat re-creation required as replacement for anticipated losses on Natura 2000 and other designated sites due to sea-level rise:

• A 2006 Defra study – National Evaluation of the Costs of Meeting Coastal Environmental Requirements (NEOCOMER) FD2017 – identified the likely extent of the impact on designated sites (Natura 2000 and SSSI) and costs of replacement habitat, but did not identify the overall losses and replacement needs for all BAP habitat lost in this way. • CHaMPs – Coastal Habitat Management Plans – cover 9 major site complexes and identified the nature of freshwater, brackish and saline habitats at risk. However, the CHAMP reports do not consider the relative ease with which different types of lost habitat might be re-created, nor does the suite of CHaMPs cover the entire coastline at risk. • The Environment Agency’s Regional Habitat Creation Programmes are drawing on CHaMPs, Catchment Flood Management Plans and Shoreline Management Plans to identify potential locations for habitat replacement, but this work is not complete and, crucially, focuses on replacement needs in the context of statutory requirements (i.e. independent of wider UK BAP habitat restoration and creation requirements) and within given regions rather than at a national scale. • At a national level, the joint Wetland Vision has identified broad opportunities for large-scale wetland habitat creation, but is based on existing national inventory data and without local considerations of feasibility or considerations of future effects of climate change. Thus, it will need to be developed further and use regionally and locally updated habitat inventories to inform decision- making on the ground. • Local and regional visions or habitat planning frameworks exist across the country at varying levels of detail, and to a range of different criteria. The degree to which these identify habitat replacement needs or contribution to UK BAP targets is variable.

AIMS AND OBJECTIVES The aims of this project are: 1. To achieve a strategic national (England only) overview of the extent of freshwater, brackish, and saline BAP habitat behind the natural and defended coastline that may be lost over the next 100 years due to the effects of climate change and sea-level rise (Project Phase 1); 2. To categorise the feasibility of recreating each type of habitat and the timescale required (Project Phase 1);

The project will build on work done at regional level (Regional BAPs, CHaMPs, CFMPs, SMPs) and at national level (NEOCOMER, UKBAP and Wetland Vision) to

4 http://www.branchproject.org/

5 http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=326

3 propose some large-scale areas for habitat creation which will give optimum gains for wetland creation, and offer maximum synergy to meet the needs of the range of drivers identified.

The project will be delivered in two separate phases. Contractors are being asked to tender for Phase 1.

Phase 2 will:

• Identify locations that offer opportunities for sustainable, large-scale re-creation of these habitats at the coast or inland (Project Phase 2).

The elements of Phase 2 are also given in Appendix 1.

Phase 1 – Comprehensive identification of habitats at risk: • Review existing information using updated regional and local inventories where available. Identify gaps in coverage under CHaMPs, NEOCOMER, SMPs. • Produce a breakdown of the area of freshwater, brackish, and saline BAP habitat types at risk over 0-20, 20-50, and 50-100 year timeframes given a range of sea-level rise scenarios (tenderers are invited to propose scenarios and timeframes in their tender, although the successful contractor will be expected to agree these with the steering group at the start of the project). The BAP habitats to be considered are those which are located inland of the current natural or defended coastline. The project is not considering intertidal habitat (mudflat and saltmarsh). The project will include and differentiate between BAP habitat located behind the current natural and defended coastline, and within and outside designated sites (SSSI, SACs, SPA, and Ramsar sites) • A methodology and criteria for identifying habitat areas at risk, including the habitat inventories that will be used, should be developed and agreed with the project steering group. • Develop a simple categorisation of the ease of practical re-creation of each habitat type and the broad timescales likely to be required in order for the habitat to become ecologically functional. • Using this categorisation (once approved by the project Steering Group) provide a high-level assessment of ease and potential timescale for the predicted potential habitat creation that will be required to fulfil legal duties and to support BAP targets given a range of sea-level rise scenarios. • Identify gaps in the coverage of freshwater, brackish and saline habitats at risk by the Environment Agency’s Regional Habitat Creation Programme, including: o Areas of habitat at risk but not covered by existing or planned Environment Agency programmes (e.g. natural coastlines or those defended by private seawalls); o Other considerations not covered by Regional Habitat Creation Programmes such as conservation objectives or location of scarce or rare species.

From the above, derive an overall best-estimate of the aggregated scale of habitat replacement needed, together with the timescales needed for developing new habitat, for both Natura 2000 and BAP requirements.

4 ISSUES AND SCOPE 1. It is envisaged that the focus of the project will be confined to the vulnerable freshwater, brackish and saline habitats located behind the current natural and defended coastline in England only (i.e. not intertidal habitats). This will principally be coastal and floodplain grazing marsh, saline lagoons, freshwater open-water habitats, lowland fens, and reedbeds, but may include wet woodland, lowland heathland, lowland meadows, lowland woodlands, and purple moor grass and rush pastures. 2. The project should consider an agreed range of sea-level rise scenarios and their implications for coastal habitats over 0-20, 20-50 and 50-100 year timeframes. 3. It is important to the aims of the project that a comprehensive overview is produced of the BAP habitat area that may be lost around the entire English coast. However, given that available funds are finite, it would help if contractors could provide a breakdown of costs based on cost per Shoreline Management Plan unit. This would help in reducing the geographical scope of the project if necessary.

USES AND USERS OF THE RESULTS The outputs from the project will be used by a range of governmental organisations to assist delivery of their obligations under the Habitats and Birds Directive and in support of the Government’s targets for biodiversity under the UK Biodiversity Action Plan. In addition, the identification of locations suitable for the strategic re-creation of habitats will be of use to a range of non-governmental organisations and planning authorities.

Outputs will be used to inform policy development, spatial planning and best-practice advice. The research will contribute to development of an integrated coastal zone adaptation strategy, and the production of guidance and policy tools aimed at preventing the loss of biodiversity as a result of climate change.

OUTPUTS The project outputs will include: • Project Inception Plan. • Interim Report (5 hard copies and 1 electronic copy in Word format). • Draft Report (5 hard copies and 1 electronic copy in Word format). • Final Report (10 hard copies and 1 electronic copy in PDF and Word format). • An Excel spreadsheet inventory of habitats and priority species vulnerable at the coast, and accompanying GIS layers in a format to be agreed. • Non-technical summary. • Agendas and Minutes from meetings.

Outputs must be designed to communicate effectively with decision-makers, conservation managers and other stakeholders.

It is anticipated that the contractor would be able to work to a proposed plan in conducting research, but effective liaison with the Contract Manager will be required, especially if any difficulties arise which could put the project at risk. Risk registers must be maintained and reviewed at every Project Steering Group meeting. An interim report is expected to enable Defra to gauge progress towards meeting the aims and objectives of this work.

5 The structure of the final report should be agreed between the nominated officer and the contractor. It must include an introduction, giving the background and policy relevance of the project. The contractor will be expected to provide a Table of Contents for agreement prior to submission of the final report.

The draft final report will be subject to a process of review. A minimum of six weeks will be required for comments on draft end products to be returned by Defra and the Project Steering Group. The draft final report must therefore be delivered to Defra two months prior to end of contract. This allows six weeks for peer review, collation of comments, etc which leaves two weeks for the successful tenderer to amend final report and re-submit.

7 PUBLICATION It is the intention of Defra to publish the results of the work through one or more routes:

Non-technical summary report for decision-makers containing headline results and recommendations.

A final report of no more than 50 pages covering the policy and scientific background to the work, the methodologies employed, results, conclusions and recommendations suitable for publication on the Internet. The report will contain an executive summary of not more than three pages and should be written in Plain English. If appropriate, papers for referred scientific journals may also be prepared.

In addition, the contractor shall provide an Executive Summary (no more than 2 sides A4) in the format provided in SID 5 at http://www.defra.gov.uk/science/documents/funding/sid5.doc

Following peer review, the approved final report suitable for publication must be provided by the contract end date. Further details on publications are given in Annex A. Discussions on these arrangements, including costs and dissemination, would take place towards the end of the contract and may require a variation to the contract to cover any additional costs. Tenderers should therefore indicate their willingness and ability to undertake responsibility for publishing the final report to Departmental design standards on this basis.

Interim reports (maximum 5 copies) to include a summary of progress towards achieving objectives against the timetable and identifying any proposed changes to the programme of work.

8 QUALITY ASSURANCE Tenderers should be aware that an application cannot be accepted unless you have read ’The Joint Code of Practice for Research’. Please confirm that you are aware of the Code and that you will use your best efforts to work towards full compliance with it. Further details are available at: www.defra.gov.uk/science/publications/2003/QACoP_V8.pdf

Tenderers must display a good understanding of the issues involved. They should also have the ability to edit and present written material in a clear, concise and informative style. Tenderers will provide details of their quality assurance procedures to demonstrate how the quality of inputs and outputs will be ensured. The final report will be subject to peer review and the contractor will be expected to respond in detail to reviewers comments and amend the final report as appropriate.

6 Tenderers should provide an assessment of risks, together with mitigation dn contingency proposals.

9 PROJECT MANAGEMENT

The Contract will be managed in accordance with the Department’s ‘Standard Terms and Conditions for Research and Development Contracts’.

The contractor will be managed by an official of the Department who will act as Contract Manager responsible for the day to day management of the contract. The contractor will appoint a project manager who will act as the principal point of contact for the Department.

The nominated official of the Department will be able to contribute to the management of the project through a series of informal and steering group meetings with the contractor during the course of the project.

The Department will establish a small Steering Group that will include representatives from the Department, Natural England, Environment Agency, Joint Nature Conservation Committee, selected members of the EBS Towns, Cities and Development Special Interest Group. The Steering Group will monitor progress and provide guidance on objectives; output, information needs on technical and analytical matters, and will be chaired by the Contract Manager at times to be agreed. Steering group meetings will be held at approximately three month intervals. The contractor will be responsible for organising and providing the secretarial and administrative support for these meetings. The Contract Manager will assist with booking meeting rooms, video or telephone conference links.

Before the end of the contract, the contractor may be requested to attend a meeting with the Department to discuss the management and performance of the contract with a view to informing each other of any strengths and weaknesses exposed.

As already outlined, regular contact via telephone calls or emails is expected between the Defra contract manager and the successful tenderer in order to ensure any emerging issues can be addressed to minimise any risk to non-delivery.

Tenderers are also requested to note the tender evaluation criteria given in this project specification. It includes an assessment of any opportunities for information dissemination identified and described in your tender.

10 TIMING

The contract will be expected to last twelve months. The anticipated start date will be shortly after the tender submission date, pending the results of the tender review process, with the commencement of a start up meeting. In addition to the key milestones, regular contact and updates (in the form of emails, telephone calls or meetings) is expected with the Defra Contract Manager during the course of the contract. These updates should also highlight any problems or anticipated difficulties and give accounts of how these will be resolved.

All submissions must include a detailed work programme based on milestones, which will be linked to the payment schedule.

7 10.1 PROGRAMME OF WORK AND MILESTONES Tenderers are invited to propose a work programme designed to meet the objectives, requirements and timetable. Tenders should include a time schedule for the work that identifies the main tasks and key milestones, and key outputs that will be used to monitor progress (see enclosed ‘Guidance on Submitting a Tender for Defra Research’ note for further details). The timetable will need to accommodate the review of outputs, attendance to project meetings and regular contact with the Contract Manager.

11 COSTING AND PAYMENT SCHEDULE

A fixed fee must be given as part of the submission. Transparent costings (including staff, grading, number of days, daily charge out rate, overheads) should be provided for each task outlined in the project specification. Meetings should be assumed to be held in Defra meeting rooms in Bristol or London and costed accordingly. Payment will be proportioned through the contract length and paid on milestones. The successful tenderer should submit a payment schedule using the milestones A full work programme will also need to be provided in the tender submission and must include all reporting milestones.

It is expected that all costs associated with the production and publication of the final reports for Phase 1 (which will include the proposal and estimated costs for Phase 2) form part of the fixed cost provided within the tender submission. Any maps will need to be produced using a GIS format agreed by Defra to ensure digitised information can be used for other Government purposes.

It is important to the aims of the project that a comprehensive overview is produced of the BAP habitat area that may be lost around the entire English coast. However, given that available funds are finite, it would help if contractors could provide a breakdown of costs based on cost per Shoreline Management Plan unit. This would help in reducing the geographical scope of the project if necessary.

12 PROJECT TEAM (INCLUDING SUB CONTRACTORS) Details of the project team (including CVs) should be supplied indicating the experience of the individuals and their role and responsibility in the delivery of the project outputs. The organisation of the project team should be linked to the work programme, indicating the grade of staff and number of days allocated to specific work area/task outlined in order to deliver the project aims and objectives (see ‘Guidance on Submitting a Tender for Defra Research’ note for further details). It is important to demonstrate project management and each persons role, suitability and value added to the project.

Any substitution or change to the project team will need to be agreed by Defra after submission of the proposal and award of contract.

13 FORMAL PROJECT REVIEW

The Department may formally review the project within 3 months of the start date. Progress to date and the detailed work programme for the remainder of the project will form part of the review, which is designed to ensure that the project continues to meet the Department's needs and provides value for money.

8 14 CONTRACT TERMS AND CONDITIONS

The contractor is expected to have read and agreed to the contract terms and conditions attached to the project specification.

15 ELECTRONIC SECURITY

Electronic media of any type or format supplied to the Department by the Contractor must be checked for viruses before shipment. The Contractor must provide details of the computer virus detection and virus eradication software (or hardware) that is used to prevent infection and the frequency at which it is updated.

16 EVALUATION CRITERIA

Tenders will be assessed against the criteria set out below. It is worthwhile trying to assess your own proposal against these criteria before you submit it. It is important to realise that the Panel will score proposals against each of these criteria. For example, if your proposal is of high quality, but does not provide an adequate description of how the results will be transmitted to the appropriate audience, it will probably be unsuccessful.

weighting, as % within Max Score category

1. Quality of proposal, (45% of the total for the four assessment categories)

Clarity of proposal (particularly 20 10 work plan and deliverables) Understanding of, and relevance 20 10 to, Defra requirements (in particular, the adequacy of outputs and understanding of any sampling and/or statistical analysis) Soundness and logicality of 10 5 methods Degree of scientific merit and, 10 4 where appropriate, innovation Realism and measurability of 10 4 milestones Identification and proposed 10 4 solutions to potential problems/risks Serious weaknesses which 10 4 threaten success Probability of success 10 4 Sub Totals 100 45 2. Details of contractor (20 % of the four assessment categories) Expertise, experience and 30 6 balance of team

9 Defra’s previous experience of 20 4 using the team/ team members (if any) Risks if important team members 20 4 drop out Adequacy of subcontractors (if 30 6 any) Sub Totals 100 20 3. Cost (20% of the total for the four assessment categories) Transparency and correctness of 25 5 presentation Fairness/reasonableness for the 25 5 level of work and expertise required Appropriateness of ratio of senior 25 5 to junior staff time Clarity of each team member’s 25 5 contribution and value added Sub Totals 100 20 4. Long-term (15% of the total for the four assessment categories) Adequacy of plans for the 33 5 dissemination of results Prospects for technology transfer 13 2

Prospects for exploiting 13 2 intellectual property Likely long-term relevance of the 41 6 work Sub Totals 100 15 Summary Total Score 400 100

10 Appendix 1 The possible objectives for Phase 2

Targeted locations for strategic habitat creation Overall objective: Produce a shortlist of recommended locations where there are feasible and sustainable opportunities for large-scale wetland habitat replacement to meet biodiversity requirements.

A methodology or decision-making tool for producing the opportunities shortlist should be developed so that the decision-making process is logical, scientifically robust and transparent. It will involve establishing selection criteria, and accommodating practical considerations such as limitations of available data. These opportunities should be based on (among others): • Wetland Vision national maps. • Published Regional BAPs and other regional/local Visions or programmes identified under wetland Vision. • Wider discussions with Regional BAP coordinators and Wetland Vision regional partners. • Criteria for selecting habitat replacement / recreation to meet other biodiversity objectives – eg bittern habitat replacement criteria • Targeting criteria for wetland creation options under agri-environment schemes (HLS) • Any principles derived from Natural England’s JCA climate change adaptation pilot studies • Any other reliable, recognised sources of information

It will be important to: • Confirm feasibility of these options with partners at England and regional level under the England Biodiversity Strategy Biodiversity Integration Group (BIG). • Identify any barriers to delivery posed by regional development plans, Catchment Abstraction Management plans, River Basin Management Plans or other alternative land-use plans. • Identify any potential barriers to delivery posed by existing land use constraints, eg aircraft safeguarded zones. • Identify any synergies with other BAP programmes or targets at the UK, national or regional level – e.g. woodland BIG, coastal BIG - or other relevant programmes, such as River Basin Management Plans. • Indicate where large-scale opportunities exist for coastal systems to adapt and thereby enable biodiversity needs to be met progressively and in a timely fashion. • Indicate the major advantages and disadvantages of each recommended location. • Demonstrate that the locations identified are likely to be sustainable in the face of predictions of both climate and coastal change.

The primary objective of identifying location opportunities is to meet requirements for legally-required habitat compensation and habitat restoration/creation requirements under the UK BAP. However, it will also be important to identify the opportunities and constraints within each of the short-listed locations for achieving multiple benefits and provision of ecosystem services through: • Discussions with the Environment Agency and Defra to determine wider flood risk management opportunities. • Discussions with relevant water companies and Environment Agency to determine opportunities for contributing to water quality and water resource management (e.g. diffuse pollution, aquifer re-charge) objectives (including

11 review of options and strategies identified by water companies in their Water Resource Management Plans and Water Safety Plans). • Discussions with relevant leads on archaeological heritage, recreation, landscape and access to determine opportunities for these societal benefits (including options identified in existing visions and strategies).

A final component of Phase 2 of the project will involve the estimation of costs and the identification of potential delivery and funding mechanisms: • Broad estimates of costs of land purchase, capital works and ongoing management over timescale bands. • A short cost-benefit assessment. • Programme fit with priorities for objectives of funding streams from statutory partners – Environment Agency flood risk management, Natural England BAP and Environmental Stewardship. • Programme fit with external funding sources, including national (Heritage Lottery Fund, Big Lottery Fund, independent funding bodies) and international (Interreg and LIFE funds).

Appendix B Project Organisation

A steering group oversaw this project. The steering group members comprised:

• Rob Cathcart (Natural England, steering group leader);

• Helen Pontier (Defra project manager);

• Alastair Burn, Iain Diack, Tim Collins, Jon Webb and Jon Curson (Natural England); and

• Amy Shaw, nee Parrott (Environment Agency).

The consultant team comprised the following key members:

• John Pomfret and Andy Brooks (Entec UK Ltd, Entec project director and manager respectively) with support from Graham Morgan;

• Ben Gouldby and Valerie Bain (HR Wallingford project director and manager respectively) with support from Gordon Glasgow and others;

• Owen Mountford (CEH).

Appendix C Sources of Mapping Data and GIS Process Undertaken to Derive Lakes and Ponds Datasets

Data sources

Designated sites

Mapping of sites with national and international designations was obtained from www.gis.naturalengland.org.uk on 11 December 2009. The data obtained comprised Local Nature Reserves, SSSI, SAC, SPA and Ramsar and all datasets are dated 18/06/09.

The steering group also requested that the team consider County Wildlife Sites. However no nationally-based mapping of these sites could be located and these are therefore not considered further in this study.

National-scale mapping

National scale habitat mapping is available from Natural England’s website (www.gis.naturalengland.org.uk) for all the habitats listed included in the study apart from the freshwater open-water habitats. The GIS layers for coastal and floodplain grazing marsh, saline lagoons, lowland fens, reedbeds, wet woodland, lowland raised bog, purple moor grass and rush pastures were downloaded from www.gis.naturalengland.org.uk/pubs/gis/gis_register.asp on 23/7/09. Data and versions were:

• DRAFT Coastal floodplain and grazing marsh v1.1;

• DRAFT Fens v1.2;

• DRAFT Lowland raised bog v1.2;

• Purple moor grass and rush pastures v2.01;

• DRAFT Reedbeds v1.2;

• DRAFT Saline lagoons v1.1;

• DRAFT Wet woodland v1.1.

Note: The wet woodland dataset has now been withdrawn by Natural England and replaced by a composite deciduous woodland BAP dataset, which includes “Lowland mixed deciduous woodland, lowland beech and yew woodland, wet woodland, upland oakwoods, upland mixed ashwood and upland birchwood”. It is the deciduous woodland dataset that has been used in the modelling and analysis of extent of habitat at risk of loss due to climate change however the decision to use the deciduous woodland dataset was only taken following the interrogation of the wet woodland dataset as part of the habitat verification process described below.

Regional-scale mapping

Updated regional datasets were obtained, where available and complete, from the following organisations (data supplied)15:

• Natural England – North East Coastal floodplain and grazing marsh (last modified: 20/02/09), Fens (last modified: 24/02/09), Lowland raised bog (last modified: 27/10/03), Purple moor grass and rush pasture (last modified: 24/02/09), Reedbeds (last modified: 24/10/08), Saline lagoons (last modified: 03/10/08), Wet woodland (last modified: 20/02/09)) and North West (Cumbria Lowland fens (last modified: 17/04/09), north west Lowland Fens (last modified: 06/05/09);

• Norfolk County Council – Coastal and Floodplain Grazing Marsh (last modified: 24/11/09), Lowland Fens (last modified: 11/12/09) and Reedbeds – Norfolk and Suffolk (last modified: 09/12/09);

• Sussex Wildlife Trust – Sussex Reedbeds (last modified: 15/04/08);

• Thames Valley Environmental Records Centre – Coastal and floodplain grazing marsh (v.5 - Jan 2009), Eutrophic standing waters (v.5 - Jan 2009), Lowland fens (v.5 - Jan 2009), Lowland fens and Coastal and floodplain grazing marsh (unknown version), Ponds (January 2009), Purple moor grass and rush pasture (v.5 - Jan 2009), Reedbeds (v.5 - Jan 2009), Saline lagoons (unknown version) and Wet woodland (v.5 - Jan 2009).

Entec was not made aware of any other updated datasets.

New habitat mapping

When this project commenced there was no existing GIS shapefile for eutrophic standing waters and no shapefile or spreadsheet listing for ponds in England. A GIS shapefile was required for each to enable an assessment of the area of habitat at risk to be quantified during later modelling.

For eutrophic standing waters, the Environment Agency supplied a spreadsheet (Eutrophic Lakes 28_09_09.xls) that listed 3919 eutrophic standing water bodies in England. Data provided include name where available, easting and northing, national grid reference, SSSI name where applicable and SAC name where applicable. A GIS shapefile was derived from this point data by matching and filtering OS Mastermap data. Before analysing the lake points, the Mastermap data required some pre-processing to remove non-essential features. In order to remove rivers, streams and drains, the thickness of each polygon was calculated, and used to filter non-standing waterbodies. The resulting output was then dissolved to remove overlaps and amalgamate the Mastermap THEME classes to form whole waterbodies. The final dataset was matched against the Eutrophic Lakes 28_09_09.xls

15 These were datasets available at the time the habitat mapping element of this project was undertaken. These datasets may now have been audited by Natural England and/or new regional datasets may now have become available. However they have not been gathered for this project.

spreadsheet. Due to issues of accuracy with the grid references within the spreadsheet and the physical shape of certain waterbodies or clusters of waterbodies (e.g. where there are many waterbodies in close proximity but the data point misses all of them), it was not possible to match all 3919 eutrophic waterbodies. Following a discussion with the Environment Agency, a decision was taken to select only waterbodies that contained the lake points, rather than including potential non-eutrophic waterbodies in the final output. The final output maps 3051 unique, eutrophic waterbodies.

To derive a shapefile indicating the distribution of ponds in England, following the removal of non-essential Mastermap features in the lakes analysis, the waterbodies were filtered by size and thickness to produce a ponds dataset. First, polygons with an area less than 25 m2 and greater than 2 ha were removed. Second, the polygons were filtered on thickness to remove ‘artefacts’ from drains or stream curves. The next step was to dissolve the ponds, ensuring no overlaps or duplicates remained. The resulting dataset was then compared against the ponds dataset provided by South East Local Records Centre and measured for accuracy and to test methodology. Out of the 105 ponds in the SE LRC dataset, there were 100 derived polygons, with the remaining 5 ponds being either uncertain as to their current status or drains. The final ponds dataset consists of approximately 388,000 unique waterbodies. It is common for clustered groups of waterbodies to be defined as one entity. However due to the lack of adequate name metadata, this grouping was not undertaken in this analysis.

It should be noted that whilst a GIS shapefile has been derived indicating the distribution of ponds in England, the coverage includes all ponds (extracted from OS Mastermap at least) and not just BAP priority ponds, which are defined as permanent and seasonal standing waterbodies up to 2 ha in extent which meet one or more of five criteria. It was beyond the scope of the project to screen all the ponds in the GIS shapefile for their priority status. In an attempt to assess the likelihood that any of the ponds included in the shapefile is a priority pond, Jeremy Biggs of Pond Conservation supplied the following useful information:

• Ponds without inflows and with a buffer of 100 m or more of semi-natural habitat around them (e.g. non-intensive grazing marsh grassland) have an 85% chance of being priority ponds;

• Ponds with inflows have a much lower likelihood of being priority ponds, even with a 100 m buffer of semi-natural land around them. For these ponds there is only a 50% probability that they will be priority ponds.

In the context of this project it was still not easy to use these points to define which of the ponds mapped should be priority ponds because the project only looked at open-water and wetland BAP habitats and not at all semi-natural habitats. Following discussion with Jeremy Biggs, the approach adopted for the purposes of this project was to assume that any pond located within another of the BAP habitats being considered was a priority pond and those outside were not. Whilst this will underestimate the number of priority ponds outside of existing wetland BAP habitats, it will also probably over-estimate the number of priority ponds within the BAP habitats. Although it is not clear, without further detailed GIS analysis, whether these would balance out, the adopted approach was considered to be the most pragmatic and straightforward for the purposes of this project.

Coastal Habitat Management Plans and Shoreline Management Plans

Natural England’s seven Coastal Habitat Management Plans (CHaMPs) were examined for more recent data mapping. It was concluded f the review that the documents covered limited areas of the coastline and add little to the mapped habitat resource of potential use for this project.

A number of Shoreline Management Plans were examined. These cover a much greater extent of the coastline but do not present mapping of habitats inland of the natural and defended coastline. There was a high-level representation of saltmarsh extent in some of the documents, but saltmarsh was not included in this project.

Appendix D Details of the Habitat Verification Process

Review of the nationally mapped data attributes

Habitat extents

The UK BAP Priority Habitat Descriptions (http://www.ukbap.org.uk/library/UKBAPPriorityHabitat DescriptionsfinalAllhabitats20081022.pdf) provide an indication of the extent of BAP habitats in the UK. These are presented in Table D.1 along with the extent of habitats represented by the national mapped data.

Table D.1 Comparison of the UK BAP Published Habitat Extents/Estimates with the extents in the habitat inventory for England

Habitat UK BAP published extent Inventory extent for England (ha)/No. (ha)/estimate/No.

Coastal and floodplain grazing marsh UK ca 300,000 ha, England 200,000 ha 229,762 ha

Saline lagoons Not stated 1,479 ha

Eutrophic standing waters (lakes) England estimate 54,000 ha, 3,919 lakes* 22,287 ha, 3,051 matching polygons

Ponds No area quoted/80,000 outside curtilage 25,589 ha/388,197 ponds nationally, 77,639 (gardens) priority ponds assuming 20% of the total

Lowland fens 3,000 ha in Broadland. No national figure 11,7991 ha given

Reedbeds UK 5,000 ha 66,365 ha

Wet woodland UK 50-70,000 ha (crude estimate) 15,8437 ha

Lowland raised bog Ca 500 ha 9,964 ha

Purple moor grass and rush pastures UK ca 56,000 ha, England ca 5281 ha 22,057 ha

* Note that the estimated extent of eutrophic standing waters comes from the UK BAP Priority Habitat Description whilst 3,919 is the number of waterbodies included in the Environment Agency sourced data.

The uncertainties in the mapping, compared to the published estimated resources are clearly illustrated in Table D.1, with the greatest over-estimates being reedbeds, potentially over-estimated by 1,300%, and lowland raised bog, over-estimated by 900-1,000%.

Total mapped areas of these habitats located within the Environment Agency’s coastal floodplain 16 are presented in Table D.2 below, along with an indication of the percentage that these areas represent of the total mapped resource.

16 The Environment Agency’s flood zone 2 extent indicates areas likely to be affected by a major flood, with up to a 0.1 per cent (1 in 1,000) chance of occurring each year. The extents are defined on the basis of the risk of flooding from fluvial, tidal or tidal/fluvial sources.

Table D.2 Comparison of the published habitat extents/ estimates with the extent of the selected BAP habitats located within the coastal floodplain

Habitat Inventory extent for England (ha)/No. Percentage of total

Coastal and floodplain grazing marsh 103,734 ha 43%

Saline lagoons 810 ha 54.5%

Eutrophic standing waters 1,972 ha/289 No 8.8% in terms of area

Ponds 2,109 ha, 18,174 No, 3,634 priority assuming 5.2% area/3% number 20% of the total

Lowland fens 11,188 ha 9.5%

Reedbeds 32,122 ha 47.2%

Wet woodland 143 ha <0.1%

Lowland raised bog 3,501 ha 35.1%

Purple moor grass and rush pastures 4,136 ha 18.7%

Note: This is based on the Nationally Mapped Habitat Datasets available from www.gis.naturalengland.org.uk. These are not the datasets that were used in the analysis of possible habitat losses.

Analysis of data attributes

Analysis of the attributes allocated to the GIS polygons for these habitats provide a further indication of the degree of uncertainty inherent in the mapping. Each polygon is assigned one of the following ‘PRIDET17’ values:

• ‘Definitely is’ (i.e. definitely is the habitat across the entire polygon);

• ‘Definitely present within polygon but not mappable’ (i.e. the habitat is present in the polygon but specific distribution data were not available from which to map the habitat distribution);

• ‘Probably the priority habitat but some uncertainty of interpretation’; and

• ‘Probably the priority habitat but some uncertainty of interpretation and mapping’.

The percentages of the polygons for each habitat allocated to the ‘PRIDET’ values are presented in Table D.3.

17 Entec is not aware of what ‘PRIDET’ is short for but the database entries associated with the ‘PRIDET’ label appear to indicate the degree of confidence that the associated polygon reflects the habitat to which it has been assigned.

Table D.3 Analysis of the attributes allocated to the GIS polygons of the nationally mapped habitat data

Habitat Polygon PRIDET Value

Definitely is (%) Definitely present Probably the Probably the within polygon but priority habitat but priority habitat but not mappable (%) some uncertainty of some uncertainty of interpretation (%) interpretation and mapping (%)

Coastal and floodplain grazing 0 0 100 0 marsh

Lowland fens 3.4 44 52.6 0

Lowland raised bog 79.5 2 18.4 0

Purple moor grass and rush 7.9 55 36.5 0.5 pastures

Reedbeds 1.9 63.9 34.2 0

Saline lagoons 88.3 7.3 4.3 0

Wet woodland 0 0 100 0

Eutrophic standing waters* n/a n/a n/a n/a

Ponds* n/a n/a n/a n/a

* The extents for eutrophic standing waters and ponds have been extracted from recent OS Mastermap data and hence do not have PRIDET values although they are as accurate as OS Mastermap allows.

The relatively low values in the ‘Definitely is’ category illustrate the high level of uncertainty inherent in the mapping available, with coastal and floodplain grazing marsh, reedbeds and fens apparently the most uncertain based on this analysis. An example that puts this issue into context is that the published extent for reedbed is 5,000 ha in the UK but in the mapping there is one 4,835 ha reedbed polygon alone that covers the whole of Stanford Training Area SSSI, and which actually primarily comprises Breckland grassland and heath, both of which are dry habitats. This is because a small area within that polygon is in fact reedbed, but mapping does not differentiate a boundary between the habitat types within the polygon. An example of where reedbed area is over-estimated compared to the extent on the ground is illustrated in Figure 2.1. However, on the same figure there is good comparison between the nationally mapped extent of saline lagoon and the site habitat map.

Analysis was undertaken of the GIS attributes for the habitats located in the coastal floodplain to determine whether they suggest less uncertainty in these areas and, although generally better, are only slightly so (see Table D.4).

Table D.4 Analysis of the attributes allocated to the GIS polygons of the nationally mapped habitat data in the coastal floodplain

Habitat PRIDET Value

Coastal and floodplain grazing 0 0 100 0 marsh

Saline lagoons 82.6 10.8 6.6 0

Eutrophic standing waters* n/a n/a n/a n/a

Ponds* n/a n/a n/a n/a

Lowland fens 3.7 40.8 55.5 0

Reedbeds 1.9 59.8 38.3 0

Wet woodland 0 0 100 0

Lowland raised bog 90.9 0 9.1 0

Purple moor grass and rush 7.9 40 52.1 0 pastures

* The extents for eutrophic standing waters and ponds have been extracted from recent OS Mastermap data and hence do not have PRIDET values although they are as accurate as OS Mastermap allows. Note: This is based on the Nationally Mapped Habitat Datasets available from www.gis.naturalengland.org.uk. These are not the datasets used in the analysis of possible habitat losses.

Analysis was also undertaken of the PRIDET values for the updated regional data layers and Table D.5 presents the values. It is notable that a number of the south-east datasets either did not have any PRIDET value or there were many gaps, which therefore appear in Table D.5 as ‘unknown/unspecified’. This has made it difficult to comment, from this analysis, on the level of confidence that the data originators had in the data, and therefore whether there is greater confidence in these data than the national data. However, comparison at this level was possible for the north-east, north-west and Norfolk/Suffolk datasets, and for some of the south-east data. The analysis indicated that although there was apparent increased certainty that the mapping represents the features more accurately for some habitats at the regional compared to a national level (e.g. coastal and floodplain grazing marsh and purple moor grass and rush pastures in the North East, lowland fens in Norfolk/Suffolk and reedbeds (‘definitely is’ value) in the South East), this was not always the case. For example, there is a lower value for the ‘definitely is’ category of lowland raised bog in the North East compared to the national dataset. Overall the picture based on this analysis was mixed. There was therefore a need for some verification of the data themselves by comparison with site-specific data.

Table D.5 Analysis of the attributes allocated to the GIS polygons of the regionally mapped habitat data

Habitat Polygon PRIDET Value

Definitely is Definitely present Probably the Probably the priority (%) within polygon but priority habitat but habitat but some not mappable (%) some uncertainty uncertainty of of interpretation interpretation and (%) mapping (%)

North East

Coastal and floodplain grazing marsh 24.5 0 75.5 0

Lowland fens 1.86 6.8 91.3 0

Lowland raised bog 56.4 0 43.6 0

Purple moor grass and rush pastures 25.8 25.9 48.3 0

Reedbeds 33.5 63.5 2.9 0

Saline lagoons 91.6 8.4 0 0

Wet woodland 0.3 0 99.7 0

North West

Lowland Fens 8.3 71.3 20.4 0

Norfolk/Suffolk

Coastal and floodplain grazing marsh 0 0 100 0

Lowland Fens 11.6 11.1 76.9 Unknown/unspecified - 0.5

Reedbeds 1 61.4 37.5 0

South East

Coastal and floodplain grazing marsh 15.9 0 0 Unknown/unspecified – 84.1

Lowland fens 17.9 6.9 29.8 Not present but close to definition - 1.3 Unknown/unspecified - 44.2

Fens and Coastal and floodplain 0 0 0 Unknown/unspecified - 100 grazing marsh

Lowland raised bog 0 0 0 Unknown/unspecified - 100

Purple moor grass and rush pastures 7.8 29.0 23.8 Unknown/unspecified - 33.4

Reedbeds 13.4 1.3 8.5 Unknown/unspecified - 76.6

Saline lagoons 0 0 0 Unknown/unspecified - 100

Wet woodland 21.8 5.8 34.7 Unknown/unspecified - 37.7

Analysis of habitat overlaps

Analysis of the habitat layers indicated that there is significant overlap between assignation of mapped areas for some habitats within a given polygon (see Table D.6).

Table D.6 Overlaps between mapped habitats (%) within the nationally mapped habitat datasets

Habitat CFGM Lfens LRB PMGRP Reedbeds SL Woods

CFGM 4.62 5.41 20.36 24.53 3.30 0.01

Lfens 2.37 88.75 16.85 19.08 0.16 4.32

LRB 0.23 7.50 0.82 1.04 - 0.02

PMGRP 1.95 3.15 1.80 5.77 0.04 0.05

Reedbeds 7.08 10.73 6.92 17.37 21.25 0.11

SL 0.02 0.00 - 0.00 0.47 0.00

Wwoods 0.01 5.80 0.25 0.35 0.25 0.03

Note: Percentages in each column relate to the area of habitat type denoted at the head of the column. For example 7.08% of CFPGM polygons are overlapped by reedbed polygons whilst 24.53% of reedbed polygons are overlapped by CFPGM polygons. Codes for habitats are: CFGM – coastal and floodplain grazing marsh, Lfens – lowland fens, LRB – lowland raised bog, PMGRP - purple moor grass and rush pasture, SL – saline lagoons, Wwoods – wet woods.

As an example, for the reedbed polygons, the greatest overlaps are with coastal and floodplain grazing marsh and lowland fens. The degree of overlap indicated in these tables is perhaps not surprising when the habitat definitions are referred to. Extracts from the BAP Priority Habitat Statements are presented in Appendix E, which provides text and tables on the correspondence of the BAP habitats with existing habitat classifications. The National Vegetation Classification (NVC) elements are summarised in Table D.7 to show the degree of overlap possible when NVC level data are used. Based on the comparison in this table a site containing, for example, the M22 Juncus subnodulosus – Cirsium palustre fen meadow community could be included in the coastal and floodplain grazing marsh, lowland fen and/or purple moor grass and rush pasture BAP habitats. Likewise, a site containing wet woodland communities W1-W6 could be included in wet woodland and lowland fens.

Table D.7 Comparison of NVC communities considered to represent the selected priority BAP habitats

Community Group CFGM Lowland Fen Reedbed Purple Moor Lowland Wet Grass and Rush Raised Bog Woodland Pasture

Mesotrophic MG4-MG13 grassland

Mire M22-M25 M1-M14, M21-M29 M22-M26 M1-M3, M15, M18, M19, M20, M25 may be found

Swamp S5-S7, S22 S1-S20, S22, S24, S4, S24-S27 W4 S25, S27, S28

Woodland W1-W6 W2 W1-W7

Note: These NVC communities have been extracted from the respective BAP Priority Habitat Statements.

Summary

The uncertainty in habitat distribution and over-estimation of the habitat extents in the available mapped data are, at least partly, caused by the tendency in BAP policy and planning (e.g. BAP targets inter alia) to work at the “habitat level”. Although habitat definitions derive from the key environmental features related to the distribution of a species or community, it has increasingly been (mis-)used as though it corresponded to vegetation classification. In the context of the present project, adoption of the “habitat level” leads to the combining of vegetation communities (e.g. lowland wet grassland types MG4, MG5, MG8, MG12 and MG13) that each have distinct eco-hydrological requirements and tolerances to salinity (see Gowing in Wheeler et al. 2004). Hence, the apparent tolerances of “coastal and floodplain grazing marsh” (itself strictly a landscape type, rather than a habitat or a vegetation type) are confounded with the component tolerances of the NVC types that make up this BAP category. Clearly, the ideal situation would be to have access to maps of NVC communities for all areas prone to coastal and riverine flooding, but such detailed data are as yet only present for a limited number of sites.

The problem is further compounded by the overlap in the definitions of the habitats and the resulting allocation of mapped habitat areas to more than one BAP habitat. The overlaps in the habitat mapping are therefore to be expected, with resultant imprecision in terms of their extent, and the predicted impacts of flooding with saline water.

A consequence of the degree of uncertainty and over-estimation of the habitat extents in the available mapped data indicated above is that the modelling of the extents of habitat at risk from sea level rise may over-estimate the potential habitat losses. The potential for this to occur has however been reduced by the derivation of alternative BAP datasets.

Comparison of the national data with other data sources

Verification methodology - Comparison of nationally mapped UKBAP habitat dataset with site specific data

Site-specific information on the occurrence of the selected habitats was collated from published material and research or survey reports, especially those containing National Vegetation Classification survey maps for various sites across England. These were compared with national and regional BAP habitat datasets.

A sample of 92 sites (entire SSSIs, or component parts of SSSIs) was selected for which the accuracy of the national dataset could be assessed by comparison with site specific data. The sites were chosen with the aim of representing as wide a geographical coverage of England as possible, allowing for the availability of site-specific data and time available.

For each site, the spatial extent, distribution and type of habitat or habitats as shown in the national (and where available, regional) datasets were systematically compared with site-specific survey data, and the corresponding accuracy assessed.

Observations on the level of agreement between national, regional and site specific habitat data were tabulated, based on a visual comparison and using a qualitative score on the following scale:

• Total agreement (habitat types and extent match 95-100%);

• High agreement (habitat types and/or extent match 70-94%);

• Some agreement (significant mismatch in either habitat types and/or extent - 40%-69% correlation);

• Low agreement (the vast majority of habitat types and/or extent are wrong - <40% correlation).

Verification results - comparison between nationally mapped UKBAP habitat dataset with site- specific data

The data obtained from the verification process are presented in Appendix D.1 and a summary of results presented in Tables D.8, D.9 and D.10 below. A total of 157 correspondences were assessed across 92 sites. In summary, of the 92 sites assessed, at least one ‘low’ or ‘some’ agreement was assigned to 44 sites and at least one ‘high’ agreement score was assigned to 55 sites. This indicates that there is a broadly even split between sites with poor habitat mapping agreement and those with greater habitat mapping agreement.

There is some variation in mapped agreement between datasets across the regions. Mapped agreement was greatest (82% of agreement scores assigned were ‘high’) for sites in Somerset, whereas the East region has the poorest mapped agreement (96% of agreement scores assigned were ‘low’ or ‘some’). Overall, for sites in 4 of the 5 regions covered, at least 50% of the agreement scores assigned were ‘low’ or ‘some’. For habitats, the majority (68%) of habitats correspondences assessed were assigned a score of ‘low’ or ‘some’ agreement.

Table D.8 Comparison of nationally mapped habitat datasets for sites with site-specific data

Total no. of sites assessed No. of sites assigned at No. of sites assigned at No. of with no data least one ‘low’ or ‘some’ least one ‘high’ agreement agreement score score

92 44 55 6

Notes: Multiple scores were assigned to many sites if more than one habitat type was assessed for that site and therefore the number of scores allocated (105) as shown in this table does not tally with the total number of sites assessed (92).

Table D.9 Comparison of regionally mapped habitat datasets for sites with site-specific data

Region No. of No. and % of ‘low’ or No. and % of ‘high’ or No. and % no data correspondences ‘some’ agreement ‘total’ agreement assessed scores scores

North West 10 5 (50%) - 5 (50%)

East 24 23 (96%) - 1 (4%)

South East 61 46 (75%) 14 (23%) 1 (2%)

South (only Somerset sites 56 10 (18%) 46 (82%) - checked)

West 6 3 (50%) - 3 (50%)

Total 157 87 (55%) 60 (38%) 10 (18%)

Table D.10 Comparison of nationally mapped habitat datasets with site-specific habitat data

UK BAP habitat Total no. of habitat No. and % assessed No. and % assessed Other (no data) assessed correspondences as ‘Low’ or ‘Some’ as ‘high’ or ‘total’ assessed agreement agreement

CFGM 58 10 (21%) 52 (90%) -

Fen 26 20 (77%) 1 (4%) 5 (19%)

LRB 8 7 (88%) - 1 (12%)

PMGRP 12 7 (58%) 4 (8) 1 (33%)

Reedbed 27 21 (78%) 3 (11%) 3 (11%)

Wet woodland 26 26 (100%) - -

Total 157 85 (68%) 30 (24%) 10 (8%)

More specific observations on the accuracy of the BAP habitat mapping are provided below:

• There is clearly significant “double-recording” or confounding of habitats i.e. polygons frequently allocated to more than 1 habitat. For example, this is particularly prevalent in East Anglia where some sites are mapped as both all fen and all reedbed. There needs to be critical examination of the metadata in order to see what levels of confidence the approach can have in the national GIS maps;

• The reedbed habitat in particular seems to be markedly over-recorded, with large blocks ascribed to this habitat when clearly most of the land-cover is of other types e.g. Grafham and Rutland Waters and the Stanford Training Area;

• Fen and lowland raised bog are often confused and both allocated to the same place with the same extent on the basis of the peat soils, a history of peat-digging and the fact that the habitats often exist adjacent to one another as part of a peatland complex;

• Wet woodland seems to be mapped poorly, with the broad habitat map entirely focusing on moist clay woodlands on higher-lying ground, whilst ignoring even designated wet woodlands on the floodplains. The very poor representation of wet woodland resulted in the subsequent use of Natural England’s ‘deciduous woodland’ in the analysis of extent of habitat at risk of loss due to sea level rise, as referred to earlier, and also below;

• Coastal and floodplain grazing marsh is generally well mapped throughout the national dataset, although at higher altitudes (>20 m AOD) some polygons of other wet grasslands may be misallocated to coastal and floodplain grazing marsh;

• In some areas, notably the Somerset Moors, purple moor-grass and rush pasture is well-mapped, but in other areas this habitat suffers from confounding, either with fen or with coastal and floodplain grazing marsh;

• In addition to the above, a small sample of correspondences between national dataset polygons with the ‘definitely is’ PRIDET value and site-specific data were assessed covering fen, reedbed, purple moor-grass and rush pasture and lowland raised bog. Of these 10 were assigned a value of ‘low’ or ‘some’ and only two a value of ‘high’. This suggests that some uncertainty exists even within data having the ‘definitely is’ category.

Summary

On the basis of this limited sample there was relatively low agreement between national and site specific data. Apart from certain localities such as Somerset, there can therefore be relatively low confidence that the national datasets reflect the true extent, distribution and composition of the wetland BAP habitats that are the subject of this study.

Appendix D1 Habitat Verification Data

Accuracy of UKBAP habitat Dataset Accuracy of PRIDET 'definitely is' mapping 4.Verification 6.NE dataset 7.Regional or 8.Qualitative Qualitative information BAP Habitats national assessment PRIDET 'definitely assessment of 1.Region 2.County 3.Site/site unit/area checked type used 5.Verification information metadata checked dataset used of agreement 9.Other observations Observations is' habitat 'definitely is' Entire site is shown by the national data set to be fen, however based upon the NVC map the site contains 5 other habitats in addition to fen (carr, open water, dry grassland, ruderal, and fen meadow) of varying extents and PRIDET shows entire site to be fen - 1 East Yorkshire Newbald Becksies NVC Meade, R. (2008) NVC map Fen National Some/low distribution. The predominant habitat is carr however see opposite for correspondence Fen Some/low East Yorkshire Newbald Becksies NVC Meade, R. (2008) NVC map Fen Regional No data - The site is shown by the national data set to be predominantly reedbed interspersed with localised fragments of fen partially coincident with pools present at the site. However the NVC map shows 5 other habitats in addition to fen (carr, dry woodland and dry grassland, swamp, and valley mire habitats), and that the predominant habitat is dry PRIDET shows localised areas of fen woodland and carr. Localised patches of tall herb fen in the north of the site shown on the NVC map are coincident throughout the site - however see opposite 2 West Shropshire Brown Moss NVC Whild Associates (2003) NVC map Fen National Some with fen shown in the national dataset. for correspondence Fen Some The site is shown by the national data set to be predominantly reedbed interspersed with localised fragments of fen partially coincident with pools present at the site. However the NVC map shows 5 other habitats in addition to fen (carr, dry woodland and dry grassland, swamp, and valley mire habitats), and that the predominant habitat is dry woodland and carr. Localised patches of tall herb fen in the north of the site shown on the NVC map are coincident West Shropshire Brown Moss NVC Whild Associates (2003) NVC map Reedbed National Low with fen shonw in the national dataset. West Shropshire Brown Moss NVC Whild Associates (2003) NVC map Fen Regional No data - West Shropshire Brown Moss NVC Whild Associates (2003) NVC map Reedbed Regional No data - Entire site is shown by the national data set to be reedbed, however based upon the NVC map the site contains 5 other habitats in addition to reedbed (carr, open water, fen, swamp, dry woodland/scrub) of varying extents and distribution. Nonetheless, the predominant habitat shown on the NVC is reedbed which tallies well with the national 3 South East Suffolk Cornard Mere NVC RMA (2009) NVC map Reedbed National High/some data set None - South East Suffolk Cornard Mere NVC RMA (2009) NVC map Reedbed Regional No data - Entire site is shown by the national data set to be reedbed, however based upon the NVC map the site contains carr, swamp, and dry woodland/scrub and open water of varying extents and distribution. There is no reedbed shown by 4 South East Norfolk Dillington Carr NVC RMA (2009) NVC map Reedbed National Low the NVC map None - Entire site is shown by the regional data set to be reedbed, however based upon the NVC map the site contains carr, swamp, and dry woodland/scrub and open water of varying extents and distribution. There is no reedbed South East Norfolk Dillington Carr NVC RMA (2009) NVC map Reedbed Regional Low shown by the NVC map National data set shows the site dominanted by CFGM and reedbed with considerable overlap bewteen the two habitats, and no overlap for localised areas around the periphery to the west, south and east where there is just reedbed. However the NVC maps shows many habitats with varying extents and distribution, with no predominant 5 South East Norfolk Castle Acre NVC RMA (2009) NVC map CFGM National Low habitat prevailing None - National data set shows the site dominanted by CFGM and reedbed with considerable overlap bewteen the two habitats, and no overlap for localised areas around the periphery to the west, south and east where there is just reedbed. However the NVC maps shows many habitats with varying extents and distribution, with no predominant South East Norfolk Castle Acre NVC RMA (2009) NVC map Reedbed National Low habitat prevailing Regional data set shows the site dominanted by CFGM and reedbed with considerable overlap bewteen the two habitats, and no overlap for localised areas around the periphery to the west, south and east where there is just reedbed. However the NVC maps shows many habitats with varying extents and distribution, with no predominant South East Norfolk Castle Acre NVC RMA (2009) NVC map CFGM Regional Low habitat prevailing Regional data set shows the site dominanted by CFGM and reedbed with considerable overlap bewteen the two habitats, and no overlap for localised areas around the periphery to the west, south and east where there is just reedbed. However the NVC maps shows many habitats with varying extents and distribution, with no predominant South East Norfolk Castle Acre NVC RMA (2009) NVC map Reedbed Regional Low habitat prevailing National data set shows a central area of fen only. However the NVC maps shows a site dominated by carr with a PRIDET shows a central area of fen only - 6 West Shropshire Brownheath Moss NVC Whild Associates (2003) NVC map Fen National Low sedge understorey, with drier woodland around the periphery, and a small area of swamp in the south. however see opposite for correspondence Fen Low West Shropshire Brownheath Moss NVC Whild Associates (2003) NVC map Fen Regional No data - National data set shows a site dominated by fen or bog with almost total overlap between the two habitats The NVC map actually shows a site dominated by bog woodland with very localised areas of bracken, carr and mire and bog 7 Northwest Cheshire Danes Moss NVC Whild Associates (2003) NVC map Fen National Low pool habitats which Northwest Cheshire Danes Moss NVC Whild Associates (2003) NVC map Fen Regional No data - National data set shows a site dominated by fen or bog with almost total overlap between the two habitats The NVC PRIDET shows almost entire site to be map actually shows a site dominated by bog woodland with very localised areas of bracken, carr and mire and bog LRB - however see opposite for Northwest Cheshire Danes Moss NVC Whild Associates (2003) NVC map LRB National Some/low pool habitats which correspondence LRB Some/low Northwest Cheshire Danes Moss NVC Whild Associates (2003) NVC map LRB Regional No data National data set shows PMGRP in the west, and the remainder of the site is dominated by fen and reedbed with some considerable overlap between the two except in the area occupied by the central mere. There is some 8 Northwest Cheshire Aqualate Mere NVC Whild Associates (2003) NVC map Fen National Some/low localise bands of tall herb fen around the periphery of the mere which coincides with the dataset None - National data set shows PMGRP in the west, and the remainder of the site is dominated by fen and reedbed with some considerable overlap between the two except in the area occupied by the central mere. There is some Northwest Cheshire Aqualate Mere NVC Whild Associates (2003) NVC map Reedbed National Some/low localised bands of reedbed around the periphery of the mere which coincides with the dataset National data set shows PMGRP in the west, and the remainder of the site is dominated by fen and reedbed with some considerable overlap between the two except in the area occupied by the central mere. There are several Northwest Cheshire Aqualate Mere NVC Whild Associates (2003) NVC map PMGRP National Some localised areas of PMGRP to the west which coincide with the dataset Northwest Cheshire Aqualate Mere NVC Whild Associates (2003) NVC map Fen Regional No data - Northwest Cheshire Aqualate Mere NVC Whild Associates (2003) NVC map Reedbed Regional No data - Northwest Cheshire Aqualate Mere NVC Whild Associates (2003) NVC map PMGRP Regional No data - National data set shows site dominated by fen or reedbed with almost total overlap between the two. Also CFGM is shown in the north of the site. However The Broads Characterisation Study shows the site to be dominated by wet 9 South East Norfolk Calthorpe Broad Other Natural England (c.2004) Broad Characterisati Wet woodland National Low woodland None - Regional data set shows site dominated by fen or reedbed with almost total overlap between the two. Also CFGM is shown in the north of the site. However The Broads Characterisation Study shows the site to be dominated by wet South East Norfolk Calthorpe Broad Other Natural England (c.2004) Broad Characterisati Wet woodland Regional Low woodland National data set shows site dominated by fen or reedbed with almost total overlap between the two. However The 10 South East Norfolk Broad Fen Other Natural England (c.2004) Broad Characterisati Wet woodland National Low Broads Characterisation Study shows wet woodland within peripheral areas of the site None - Regional data set shows site dominated by fen or reedbed with almost total overlap between the two. However The South East Norfolk Broad Fen Other Natural England (c.2004) Broad Characterisati Wet woodland Regional Low Broads Characterisation Study shows wet woodland within peripheral areas of the site National data set shows site dominated by fen or reedbed with almost total overlap between the two. However The 11 South East Norfolk Smallburgh Fen Other Natural England (c.2004) Broad Characterisati Wet woodland National Low Broads Characterisation Study shows a site dominated by wet woodland None - Regional data set shows site dominated by fen or reedbed with almost total overlap between the two. However The South East Norfolk Smallburgh Fen Other Natural England (c.2004) Broad Characterisati Wet woodland Regional Low Broads Characterisation Study shows a site dominated by wet woodland National data set shows site predominantly containing fen and reedbed with considerable overlap between the two, PRIDET shows 4 localised areas of there are very localised areas of PMGRP and CFGM. However The Broads Characterisation Study shows extensive PMGRP - the Broads Characterisation 12 South East Norfolk Ant Broads and Marshes Other Natural England (c.2004) Broad Characterisati Wet woodland National Low areas of wet woodland distributed throughout the site. Study shows two correspond to purple PMGRP Some Regional data set shows site predominantly containing fen and reedbed with considerable overlap between the two, there are very localised areas of CFGM. However The Broads Characterisation Study shows extensive areas of wet South East Norfolk Ant Broads and Marshes Other Natural England (c.2004) Broad Characterisati Wet woodland Regional Low woodland distributed throughout the site.

H:\Projects\Ea-210\24903 Coastal Biodiversity and Climate Change\Docs\Outputs - deliverables\1st Interim Report\Appendix D\Habitat verification notes i2.xls Verification Results Page 1 of 4 4.Verification 6.NE dataset 7.Regional or 8.Qualitative Qualitative information BAP Habitats national assessment PRIDET 'definitely assessment of 1.Region 2.County 3.Site/site unit/area checked type used 5.Verification information metadata checked dataset used of agreement 9.Other observations Observations is' habitat 'definitely is' National data set shows site predominantly containing CFGM and PMGRP with considerable overlap between the PRIDET shows 2 localised areas of two. However The Broads Characterisation Study shows a small area of wet woodland in the north of the site PMGRP in the northeast of the site - this 13 South East Norfolk Ludham-Potter Heigham Marshes Other Natural England (c.2004) Broad Characterisati Wet woodland National Low coincident with an area shown as blank in the dataset. broadly corresponds with an area of purple PMGRP High Regional data set shows site predominantly containing CFGM with localised areas of reedbed to the nroth and south. However The Broads Characterisation Study shows a small area of wet woodland in the north of the site South East Norfolk Ludham-Potter Heigham Marshes Other Natural England (c.2004) Broad Characterisati Wet woodland Regional Low coincident with an area shown as blank in the dataset. National data set shows site predominantly containing PMGRP or reedbed with almost total overlap between the PRIDET shows 2 localised areas of two, with a localsied area of CFGM in the southeast. However The Broads Characterisation Study shows extensive PMGRP in the northeast of the site - 14 South East Norfolk Bure Broads and Marshes Other Natural England (c.2004) Broad Characterisati Wet woodland National Low areas of wet woodland distributed througout the site however the Broads Characterisation PMGRP Some/low Regional data set shows a site containing predominantly containing fen and reedbed with considerable overlap between the two, with a localised area of CFGM in the southeast. However The Broads Characterisation Study South East Norfolk Bure Broads and Marshes Other Natural England (c.2004) Broad Characterisati Wet woodland Regional Low shows extensive areas of wet woodland distributed througout the site National data set shows site predominantly containing CFGM and fen with considerable overlap between the two. However The Broads Characterisation Study shows a localised area of fen in the north of the site coincident with 15 South East Norfolk Geldeston Meadows Other Natural England (c.2004) Broad Characterisati Wet woodland National Low fen. Regional data set shows site predominantly containing CFGM and fen with considerable overlap between the two. However The Broads Characterisation Study shows a localised area of fen in the north of the site coincident with South East Norfolk Geldeston Meadows Other Natural England (c.2004) Broad Characterisati Wet woodland Regional Low fen. National data set shows site predominantly containing fen or reedbed with almost total overlap between the two. 16 South East Norfolk Stanley and Alder Carr Other Natural England (c.2004) Broad Characterisati Wet woodland National Low However The Broads Characterisation Study shows the majority of the site dominated by wet woodland None - Regional data set shows site predominantly containing fen or reedbed with almost total overlap between the two. South East Norfolk Stanley and Alder Carr Other Natural England (c.2004) Broad Characterisati Wet woodland Regional Low However The Broads Characterisation Study shows the majority of the site dominated by wet woodland National datasets for Fen, PMGRP and Reedbed each depict total cover of the NNR by that habitat - no indication of 17 Cambridgeshire Wicken Fen NVC National Trust and CEH NVC map (2004) Fen National Some South East the pattern/mosaic is given, though the layout of compartment polygons is clear South East Cambridgeshire Wicken Fen NVC National Trust and CEH NVC map (2004) PMGRP National Some [As latter] South East Cambridgeshire Wicken Fen NVC National Trust and CEH NVC map (2004) Reedbed National Some [As latter] NO wet woodland is depicted for Wicken by the National dataset, though significant areas remain (after clearance) Cambridgeshire Wicken Fen NVC National Trust and CEH NVC map (2004) Wet woodland National Low South East in the west, northern fringe and on St Edmunds Fen 18 Cambridgeshire Chippenham Fen Habitat map CEH broad habitat survey (JOM) Fen National Some Fen is depicted for the northern fringe and the southern corner, where at least some of the areas should be PMGRP South East Southern 2/3 depicted as reedbed - should in fact be a mix of fen (recorded) and wet woodland (not noted in the Cambridgeshire Chippenham Fen Habitat map CEH broad habitat survey (JOM) Reedbed National Low South East National dataset) South East Cambridgeshire Chippenham Fen Habitat map CEH broad habitat survey (JOM) Wet woodland National Low Not depicted as present, when approaching half of the NNR area is wet woodland or scrub South East Cambridgeshire Chippenham Fen Habitat map CEH broad habitat survey (JOM) PMGRP National Low Not depicted, though the fen-meadows of the north fringe could be classified as this (or fen) Accurate in the main (though identical to PMGRP map) showing fen/fen-meadow for most of the NNR except the 19 Cambridgeshire Woodwalton Fen Habitat map NE habitat map and CEH survey (JOM) Fen National Some South East central west Accurate - showing reedbed as occupying the northern compartments (though these areas are also mapped as fen Cambridgeshire Woodwalton Fen Habitat map NE habitat map and CEH survey (JOM) Reedbed National High South East and PMGRP!) Accurate in the main (though identical to fen map) showing fen/fen-meadow for most of the NNR except the central Cambridgeshire Woodwalton Fen Habitat map NE habitat map and CEH survey (JOM) PMGRP National Some South East west South East Cambridgeshire Woodwalton Fen Habitat map NE habitat map and CEH survey (JOM) Wet woodland National Low Not depicted for the NNR, though significant areas in the west and south are indeed carr or wet woodland RSPB management map and Fen Flora 20 Cambridgeshire Nene Washes Habitat map PMGRP National Some Majority of area depicted as both PMGRP and CFGM (entirely overlapping) South East survey (JOM) RSPB management map and Fen Flora Cambridgeshire Nene Washes Habitat map CFGM National Some Majority of area depicted as both PMGRP and CFGM (entirely overlapping) South East survey (JOM) Reason behind why these washes are not also depicted as PMGRP (as the Nene washes are) is not entirely clear, 21 Cambridgeshire Ouse Washes Habitat map Fen Flora surveys (JOM) CFGM National High South East though the Ouse Washes are less varied and with fewer meadows. Despite being the largest birch woodland on fen/bog peat in the UK, this site is NOT included within the wet 22 Cambridgeshire Holme Fen Habitat map NE habitat map and CEH survey (JOM) Wet woodland National Low South East woodland layer! South East Cambridgeshire Holme Fen Habitat map NE habitat map and CEH survey (JOM) Fen National Low No fen is mapped for the NNR either - admittedly it is fragmentary South East Cambridgeshire Holme Fen Habitat map NE habitat map and CEH survey (JOM) LRB National Low Bog (as latter) LCM interpreted imagery and CEH survey Areas south and east of the NNR are mapped as grazing marsh - actually a mixture of arable, improved grassland Cambridgeshire Holme Fen Habitat map CFGM National Some South East (JOM) and some reverting arable NVC and Nature reserve is actually a mosaic of open water, wet woodland, reedbed and fen, with some areas of lowland wet 23 Cambridgeshire Bassenhally Pit LNR CEH broad habitat survey (JOM) PMGRP National Low South East Habitat map grassland that do not correspond with PMGRP, but might very loosely be included within CFGM Entire polygon referred to this habitat, although eutrophic standing water and/or lake would be more appropriate for 24 East Rutland Rutland Water Habitat map CEH broad habitat survey (JOM) Reedbed National Some most of the reservoir Entire polygon referred to this habitat, although eutrophic standing water and/or lake would be more appropriate for 25 Cambridgeshire Grafham Water Habitat map CEH broad habitat survey (JOM) Reedbed National Low South East most of the reservoir 26 East Lincolnshire Baston Fen NR Habitat map CEH broad habitat survey (JOM) Reedbed National Some Entire polygon referred to this habitat, although some areas of the NR should be depicted as Fen or wet woodland Aerial photographic imagery and CEH field 27 South East Kent Romney Marsh Habitat map CFGM National High Good correspondence between existing grazing marsh habitat and the national data survey (JOM) Aerial photographic imagery and CEH field 28 South East Kent Denge Marsh Habitat map CFGM National High Good correspondence between existing grazing marsh habitat and the national data survey (JOM) Aerial photographic imagery and CEH field 29 South East Kent Walland Marsh Habitat map CFGM National High Good correspondence between existing grazing marsh habitat and the national data survey (JOM) Aerial photographic imagery and CEH field Reedbeds are locally present along the main sewers (drainage channels) and as a result of restoration, but the South East Kent Walland Marsh Habitat map Reedbed National Some survey (JOM) depicted area is exaggerated and overlaps with CFGM Aerial photographic imagery and CEH field 30 South East Kent Midrips Habitat map CFGM National High Good correspondence between existing grazing marsh habitat and the national data survey (JOM) Aerial photographic imagery and CEH field South East Kent Midrips Habitat map Reedbed National Some Reedbeds occupy significant areas here, but the depicted area is exaggerated and overlaps with CFGM survey (JOM) Aerial photographic imagery and CEH field 31 South East Kent The Wicks Habitat map CFGM National High Good correspondence between existing grazing marsh habitat and the national data survey (JOM) Aerial photographic imagery and CEH field South East Kent The Wicks Habitat map Reedbed National Some Reedbeds occupy significant areas here, but the depicted area is exaggerated and overlaps with CFGM survey (JOM) Aerial photographic imagery and CEH field 32 South East Kent The Dowels Habitat map CFGM National High Good correspondence between existing grazing marsh habitat and the national data survey (JOM) Aerial photographic imagery and CEH field Reedbeds are only very locally present along the main sewers (drainage channels) and as a result of restoration, South East Kent The Dowels Habitat map Reedbed National Low survey (JOM) but the depicted area is exaggerated and overlaps with CFGM Aerial photographic imagery and CEH field 33 South East Kent Shirley Moor Habitat map CFGM National High Good correspondence between existing grazing marsh habitat and the national data survey (JOM) Aerial photographic imagery and CEH field 34 South East Kent/Sussex Rother Levels Habitat map CFGM National High Good correspondence between existing grazing marsh habitat and the national data survey (JOM) Aerial photographic imagery and CEH field 35 South East Sussex East Guldeford Level Habitat map CFGM National High Good correspondence between existing grazing marsh habitat and the national data survey (JOM)

H:\Projects\Ea-210\24903 Coastal Biodiversity and Climate Change\Docs\Outputs - deliverables\1st Interim Report\Appendix D\Habitat verification notes i2.xls Verification Results Page 2 of 4 4.Verification 6.NE dataset 7.Regional or 8.Qualitative Qualitative information BAP Habitats national assessment PRIDET 'definitely assessment of 1.Region 2.County 3.Site/site unit/area checked type used 5.Verification information metadata checked dataset used of agreement 9.Other observations Observations is' habitat 'definitely is' Aerial photographic imagery and CEH field Reedbeds are only very locally present along the main sewers and as a result of restoration, but the depicted area is South East Sussex East Guldeford Level Habitat map Reedbed National Some survey (JOM) exaggerated and overlaps with CFGM 36 South East Sussex Pevensey Levels Habitat map CEH broad habitat survey (JOM) CFGM National High Good correspondence between existing grazing marsh habitat and the national data Apparently good correspondence between regional data for Sussex and the linear reedbeds present along some South East Sussex Pevensey Levels Habitat map CEH broad habitat survey (JOM) Reedbed Regional High havens (drainage channels) The depicted area of reedbed includes all the Fen and PMGRP, as well as some of the CFGM. Reed-dominated 37 South Somerset Gordano Habitat map CEH broad habitat survey (JOM) Reedbed National Some areas are present but the impression given by the reedbed data layer exaggerates their cover South Somerset Gordano Habitat map CEH broad habitat survey (JOM) Fen National High Precisely the same area is mapped as Reedbed and as Fen South Somerset Gordano Habitat map CEH broad habitat survey (JOM) PMGRP National High More precise mapping in the Fen/Reedbed area of Gordano (specifically the western peaty portion) Reasonably accurate correspondence with the situation, showing the main area of CFGM to be in the centre and South Somerset Gordano Habitat map CEH broad habitat survey (JOM) CFGM National High east of Gordano, where groundwater gleys predominate Avon Levels (Nailsea, Kenn, 38 South Somerset Habitat map CEH broad habitat survey (JOM) CFGM National High Generally good correspondence between grazing marsh habitat and the national data Tickenham moors etc ) Somerset Levels in the strict sense (e.g. Bleadon Level, 39,40,41,4 Habitat and South Somerset Huntspill Level, Mark Moor, CEH broad habitat survey (JOM) CFGM National High Generally good correspondence between grazing marsh habitat and the national data 2,43,44 Land-cover map Allerton Moor, Pawlett Hams, Steart etc) The polygon depicts as ONLY reedbed a very mixed habitat mosaic in and near the Golf Course which includes dry 45 South Somerset Berrow dunes Habitat map CEH broad habitat survey (JOM) Reedbed National Low dune grassland, Hippophae scrub, duneslacks, Bolboschoenus swamp, mixed rush marsh (Include Juncus subulatus ) as well as some limited reedbed - the extent greatly exaggerated 46 South Somerset Lox Yeo valley Habitat map CEH broad habitat survey (JOM) CFGM National High Generally good correspondence between grazing marsh habitat and the national data Axe valley moors (Knowle, 47,48,49,5 South Somerset Westbury, Stoke, Wedmore and Habitat map CEH broad habitat survey (JOM) CFGM National High Generally good correspondence between grazing marsh habitat and the national data 0,51 Cheddar moors) Brue valley peat moors (Aller, 52,53,54,5 Tealham, Tadham, Westhay, South Somerset Habitat map CEH broad habitat survey (JOM) CFGM National High Generally good correspondence between grazing marsh habitat and the national data 5,56,57,58 Godney, Shapwick, Catcott moors) Brue valley peat moors (Aller, Areas of high quality fen-meadow ( and dominated) are scattered through these moors - the depicted South Somerset Tealham, Tadham, Shapwick, Habitat map CEH broad habitat survey (JOM) PMGRP National High Molinia Juncus extent appears accurate, though gaps in the east (Godney/Westhay) are apparently an error Catcott moors) Fen polygons are located within a larger block allocated to LRB. Fen and CFGM seem mutually exclusive here, but 59 South Somerset Westhay Moor etc Habitat map CEH broad habitat survey (JOM) Fen National Some there is double accounting of fen and bog, and none of the area is mapped as wet woodland, despite some birch/willow woodland surviving around the site perimeter (much of the rest cleared as part of the bog restoration) Probably somewhat over-recorded or confounded with Fen - in practice all the moor mapped as on Godney series South Somerset Westhay Moor Habitat map CEH broad habitat survey (JOM) LRB National Some peats are mapped as LRB 60 South Somerset Shapwick Habitat map CEH broad habitat survey (JOM) Reedbed National Some Reasonable correspondence with abandoned diggings colonised by reed Brue valley turbary moors Some discrepancies - significant areas of raised bog and wet woodland are NOT mapped, and some polygons are 61,62,63 South Somerset (Shapwick, Westhay, Ashcott, Habitat map CEH broad habitat survey (JOM) Fen National Some recorded as CFGM and PMGRP. Sharpham heaths) Brue valley turbary moors Wet woodland is quite extensive in parts of these moors, notably at Shapwick and Canada Farm, but no attempt has South Somerset (Shapwick, Westhay, Ashcott, Habitat map CEH broad habitat survey (JOM) Wet woodland National Low been made to map this on the national GIS datasets Sharpham heaths) Upper Brue moors (Queen's 64,65,66 South Somerset Sedgemoor, Kennard and South Habitat map CEH broad habitat survey (JOM) CFGM National High Generally good correspondence between grazing marsh habitat and the national data Moors) Parrett and Cary Moors (lower and middle e.g. Somerton, 67,68,69,7 Butleigh, King's Sedgemoor, 0,71,72,73 South Somerset Habitat map CEH broad habitat survey (JOM) CFGM National High Generally good correspondence between grazing marsh habitat and the national data Stan, Southlake, Earlake, Aller ,84,75 moors, Moorlinch and the Weston Level) Areas of high quality fen-meadow ( and dominated) are scattered through Moorlinch - apparently 76 South Somerset Moorlinch Habitat map CEH broad habitat survey (JOM) PMGRP National High Molinia Juncus mapped accurately Upper Parrett (Yeo/Ivel) Moors 7,78,79,80 South Somerset Habitat map CEH broad habitat survey (JOM) CFGM National High Generally good correspondence between grazing marsh habitat and the national data (King's, West and Wet moors) 81 South Somerset Out Moor (Wet Moor) Habitat map CEH broad habitat survey (JOM) PMGRP National Some One fragment of PMGRP mapped - apparently corresponding to the most species-rich portion of Wet Moor RSPB management map and CEH broad 82 South Somerset West Sedgemoor Habitat map CFGM National High Generally good correspondence between grazing marsh habitat and the national data habitat survey (JOM) RSPB management map and CEH broad Areas of high quality fen-meadow ( and dominated) are scattered through the moor - apparently South Somerset West Sedgemoor Habitat map PMGRP National High Molinia Juncus habitat survey (JOM) mapped accurately Tone moors (North, Curry, Hay Generally good correspondence between grazing marsh habitat and the national data (some very scattered PMGRP - 83,84,85 South Somerset Habitat map CEH broad habitat survey (JOM) CFGM National High and West Moors) could not assess) Wet woodland covers a considerable part of the Waste, but all the area is allocated to either lowland raised bog or 86 East Lincolnshire Crowle Waste Habitat map CEH broad habitat survey (JOM) Wet woodland National Low fen and (except around the margins) to both these habitats Abandoned peat workings classified as both fen and bog, and often with significant areas of wet woodland that was East Lincolnshire Crowle Waste Habitat map CEH broad habitat survey (JOM) Fen National Some not included in the national datasets Abandoned peat workings classified as both fen and bog, and often with significant areas of wet woodland that was East Lincolnshire Crowle Waste Habitat map CEH broad habitat survey (JOM) LRB National Some not included in the national datasets Whole polygon allotted to Fen, to Bog & to Reedbed - no attempt made in national data to delineate which parts of LWT information and CEH broad habitat 87 East Lincolnshire Epworth Turbary Habitat map Reedbed National Some LNR should be allocated to which habitat. Wet woodland not mapped, though still present despite restoration efforts survey (JOM) to reduce extent of birch Whole polygon allotted to Fen, to Bog & to Reedbed - no attempt made in national data to delineate which parts of LWT information and CEH broad habitat East Lincolnshire Epworth Turbary Habitat map LRB National Some LNR should be allocated to which habitat. Wet woodland not mapped, though still present despite restoration efforts survey (JOM) to reduce extent of birch Whole polygon allotted to Fen, to Bog & to Reedbed - no attempt made in national data to delineate which parts of LWT information and CEH broad habitat East Lincolnshire Epworth Turbary Habitat map Fen National Some LNR should be allocated to which habitat. Wet woodland not mapped, though still present despite restoration efforts survey (JOM) to reduce extent of birch LWT information and CEH broad habitat Wet woodland not mapped for here in national dataset, though still present despite restoration efforts to reduce East Lincolnshire Epworth Turbary Habitat map survey (JOM) extent of birch Wet woodland covers a considerable part of the Moor, but all the area is allocated to either lowland raised bog or 88 East South Yorkshire Thorne Moor Habitat map CEH broad habitat survey (JOM) Wet woodland National Low fen and (except around the margins) to both these habitats Abandoned peat workings classified as both fen and bog, and often with significant areas of wet woodland that was East South Yorkshire Thorne Moor Habitat map CEH broad habitat survey (JOM) Fen National Some not included in the national datasets. Bog and wet heath more extensive than true fen

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Appendix E Extracts from BAP Priority Habitat Statements

Appendix F1 Details of Consultations Undertaken to Inform the Sensitivity Matrices

The scientific literature on the sensitivities of species and communities to saline inundation failed to provide the basis for a critical analysis of a range of salinity exposure scenarios as it tended to describe general tolerances to certain non-quantified levels of salinity. As an alternative approach, a wide range of consultees were contacted to obtain empirical observations of the effects of saline inundation of lowland open-water and wetland BAP habitats.

A brief summary of the key observations noted during the consultations is presented below:

• A few reports are available that make observations of the effects of inundation of coastal sites and/or the requirements of the habitat types. These include:

- English Nature Research Report 629 – Flood Defence Standards for Designated Sites (RPA, 2006);

- A Flood Alleviation Strategy for Broadland – Washland Development (Binnie and Partners, 1992);

- The Aquatic Flora of the RSPB’s Cantley Dyke System – 1996 (George, 1996);

- Saline lagoons – A Guide to their Management and creation (Bamber et al., 2001); and

- A Practical Guide to the Management of Saline Lagoons (Symes and Robertson, 2004).

• There are very few empirical observations of the effects of coastal inundation available. Virtually no information was discovered on the effects of saline inundation on lowland wet woodland, purple moor grass and rush pastures, ponds and lakes. This is likely to be due in large part to the fact that relatively few sites have their inundation history recorded, and where inundation has occurred, there is rarely any monitoring before and after. The majority of the site-based data that do exist are for sites in East Anglia. Sites that flood and for which observations are available include:

- Pakefield to Easton Bavents SSSI (saline lagoons and reedbeds affected);

- Cley and Salthouse Marshes (parts of the North Norfolk Coast SSSI – grazing marsh and reedbed affected);

- Walberswick Marshes (part of Minsmere to Walberswick Marshes SSSI – reedbed affected);

- Upper Thurne Broads and Marshes SSSI (chronic increase in salinity levels affecting open water, such as Hickling Broad, fen and reedbed);

- The Broads (flood events in November 2006 and November 2007 affecting sites such as Limpenhoe Meadows SSSI (grazing marsh and ditches); and Hassingham Broad (part of the Yare Broads and Marshes SSSI – open-water areas inundated);

- Additional information was obtained for Porlock Marsh in Somerset (grazing marsh, reedbed and a small area of wet woodland) and Cors Fochno SSSI (lowland raised bog).

• Factors confounding the assessment of the potential effects of saline events include the presence of saline gradients across many coastal sites and in such cases it is the flora and fauna (notably invertebrates) found along the gradient that are of greatest nature conservation importance.

Additionally, freshwater flushing is important to the maintenance of the interest on many coastal sites and the effects of saline inundation would be greater in the absence of such flushing;

• Buglife has published a report on the quality of grazing marsh ditches as indicated by their invertebrate fauna, macrophytes and water chemistry (Drake et al., 2010, Palmer et al., 2010 and Palmer and Kindemba, 2010 – see http://www.buglife.org.uk/conservation/currentprojects/Habitats+Action/Freshwater/ecologicalstatesof ditchsystems.htm). The Broads Authority hopes to detect the effects of salinity in invertebrate sample data obtained during their recent Fen Resource Survey update.

A summary of the information derived during this consultation and desk-study exercise and used to fill in draft sensitivity matrices is presented in Appendix F2.

Appendix F2 Summary of Evidence Used to Populate Draft Risk Matrices

Appendix F2

Corresponding BAP Habitat/ species described habitat Region Site/area in evidence Evidence of sensitivity to seawater inudation & recovery time Source

Standing water within ditches The Wet Grassland Guide (RSPB, 1997); on coastal levels - outwith Environmental Monitoring in the North Eutrophic standing waters Various these channels range of See evidence marshalled for grazing marsh ditches below Kent Marshes ESA 1993-1996 (ADAS, NVC types may include A1- 1997); English Nature Report RR629 A5, A8-A12, A15 and A19 (2006

Vegetation Communities of British Lakes Eutrophic standing waters National - - freshwater coastal waterboides mean conductivity 434 uS/cm (JNCC, 2006) Flooded in 1976 and 1995. Recovery of the site was rapid on both occassions Burnham Overy Staithe (several months), but future recovery predicted to be from several months, to 5 Eutrophic standing waters East Anglia Ponds English Nature Report RR629 (2006) (North Norfolk Coast) years, even up to 10 years if flooded to 0.5m depth for several weeks and not flushed Vegetation Communities of British Lakes Eutrophic standing waters National - Brackish open water brackish coastal waterbodies mean conductivity 20,000 uS/cm (JNCC, 2006) Relationship to salinity not assessed in a quantitative manner. "Fen" covers a NVC types M9, M13, M18, very wide range of eco-hydrologcial situations and water-supply mechanisms - Rodwell 1991and JOM comment (see Fen National S24 and S25 different fen types are likely to respond to saline flooding in distinct ways (see also Bryan Wheeler review) Bryan Wheeler review)

Cley (part of North Based upon a flood event in Feb 1938, during which seawater was present for Fen East Anglia Common rush English Nature Report RR629 (2006) Norfolk Coast SAC) 3 months, the species died and took between 2 to 4 years to reappear

Based upon a flood event in Feb 1938, during which seawater was present for Cley (part of North Fen East Anglia Sedge 3 months, the species died and took 2 years to begin recovery but still much English Nature Report RR629 (2006) Norfolk Coast SAC) affected

Cley (part of North Based upon a flood event in Feb 1938, during which seawater was present for Fen East Anglia Great spearwort English Nature Report RR629 (2006) Norfolk Coast SAC) 3 months, the species died and did not reappear even after 5 years

Site chronically affected by increased salinity (presuambly from increased Andrea Kelly (Broads Authority) - pers Fen East Anglia Upper Thurne Fen inundation?) comms 2009

There was a quarry on site/near site that was operational since the 1950s until 5/6 years ago. Saline water was being pumped out across a localised area of Thorne and Hatfield the site. Habitat so saline it had glasswort and estuarine invertebrate fauna. Fen East (Lincolnshire) Fen Tim Kohler (Natural England) Moors Pump turned off and in 5 or 6 years the vegetation is now reed-like/fenny. The implication is that even with periodic or regular flooding with saline water, after ~6 years reed/fen vegetation can reestablish

Salinity (conductivity) levels are 650-700 uS/cm reflecting lack of saline Coastal Squeeze and Maintenance of Fen East Anglia Suffolk Coast Tall herb fen intrusion Wetland (White Young Green, 2006)

Grassland and drainage channels - NVC types mainly Grazing marsh is not a habitat but a landscape and is best assessed, as here, Grazing marsh National MG5-13 (grassland) andA2- in terms of the grassland and aquatic components A5, A7-A11, A13-A20 (drainage channels)

Porlock Ridge and Flood defences breached in Jan/Feb 1990 and seawater was present for up to Saltmarsh, part of the 3 months resulting in almost complete 'kill' of all vegetation in the SSSI Improved/semi-improved Sue Rees (Natural England Coastal Grazing marsh South west site was formerly (brackish, brackish lagoon surrounded by saltmarsh, some alder carr, semi- grassland Specialist) - perscomms 2009 Porlock Marsh improved and improved grassland). By May 1991, most of the SSSI, which it (Somerset) is assumed includes the alder carr had reestablished

Cley (part of North 1996 flood event water remained for 4 weeks at 2m depth. Recovery time for Grazing marsh East Anglia Grazing marsh English Nature Report RR629 (2006) Norfolk Coast SAC) future similar events predicted to be 3 to 10 years. Flooded in 1976 and 1995. Recovery of the site was rapid on both occassions Burnham Overy Staithe (several months), but future recovery predicted to be from several months, to 5 Grazing marsh East Anglia Grazing marsh English Nature Report RR629 (2006) (North Norfolk Coast) years, even up to 10 years if flooded to 0.5m depth for several weeks and not flushed

Site flooded regularly in 1940s, flooded in 1953, flooded regularly in 1970s and Cley (part of North Site comprising 1980s and in Feb 1996 there was 2m depth of sea water present for at least a Bernard Bishop (Norfolk Wilsdlife Trust Grazing marsh East Anglia Norfolk Coast SAC) predominantly grazing marsh month. Despite this the site is still considered to be in good condition, albeit Reserve Warden) - perscomms 2009 some areas of the site are a bit more brackish than before.

Flood defences overtopped in Nov 2007. Cley inundated for 2 days, Salthouse Cley and Cley-Salthouse Site comprising inundated for 10 days. Cley - some damage evident initially but after 1 year no Matt Bradbury (Norfolk Wilsdlife Trust Grazing marsh East Anglia (part of North Norfolk predominantly grazing marsh damage evident. Salthouse - habitat damaged initially but two years later little Reserve Warden) - perscomms 2009 Coast SAC) damage

Site comprising At least half of the site was under sea water c.1996 for 2 weeks. The folloiwng Clive Doarks (Natural England) - Grazing marsh East Anglia Cantley Marshes predominantly grazing marsh year there was no obvious species extinction perscomms 2009

Site comprising It was agreed with Natural England that in relation to flood defences, a flood Grazing marsh East Anglia Halvergate Marshes Jeremy Halls (BESL) - perscoms. 2009 predominantly grazing marsh event once every 7 years was unlikley to cause significant damage

North Norfolk Coast Examples of regularly inundated habitats occur at this site and these habitats Roger Morris (formerly Natural England) - Grazing marsh East Anglia Grazing marsh SAC are more robust than we think perscomms 2009 Grazing marsh in dune Grazing marsh North Wales Glas Lyn Marshes Site periodically inundated but seems to be little effect upon habitat Stuart Smith (grassland specialist, CCW) slacks

Dec 1989 the marshes were flooded for 4 weeks up to 1m with salinity values Brackish and freshwater of 35-36 parts per thousand. From this event, many rush stands died. The Flood Alleviation Strategy for Broadland Grazing marsh South (Solent) Keyhaven Marsh marsh document implies that localised erratic flooding in the region of 8-15 ppt (NRA, 1992) appears not to detrimentally affect the marshes.

Salinity (conductivity) levels are 650-700 uS/cm reflecting lack of saline Coastal Squeeze and Maintenance of Grazing marsh East Anglia Suffolk Coast Wet grassland intrusion Wetland (White Young Green, 2006)

Conductivity levels of 0-2 and Na levels of <100mg/L were typical of areas not subject to maritime inundation. Of those areas sampled, NVC community MG6a Lolium perenne-Cynosurus cristatus typical sub community was Soil Nutrient Status and Botanical characterised by soils containing >300mg/L Na and conductivity >level 3; Grazing marsh East Anglia The Broads Grasslands Composition of Grassland in the Broads vegetation and soils representative of past saline inundation. MG11a Festuca ESA (Chambers et al, 1998) rubra-Agrostis stolonifera-Potentialla anserina Lolium perenne subcommunity - vegetation and soils representative of absence of recent maritime influence (<100mg/L Na)

Transitional faunal species will be replaced by saltmarsh/lagoonal species when conductivities >4000 uS/cm. Freshwater plants become stressed Grazing marsh (aquatic - National - - >200mg/L Na, whilst those favouring brackish conditions stable at 1000 mg/L The Wet Grassland Guide (RSPB, 1997) ditches) Na will become stressed if salinity fluctuates between 250 mg/L and 1000 mg/L Na.

ESA endgroup 1 and 2 (strongly brackish conditions) equivalent to English Environmental Monitoring in the North Grazing marsh (aquatic - Nature/NRA endgroup CA2 and CB1 respectively had mean conductivity levels South East North Kent Marshes Grazing marsh Kent Marshes ESA 1993-1996 (ADAS, ditches) of 7860 uS/cm and 3008 respectively. The strongly freshwater ESA endgroup 1997) 5 (equivalent DC2) had mean conductivity of 1815 uS/cm.

Bank breached in 1953, 1963, 1968, 1976, Feb 1993. Feb 1993 - entire site flooded to 1m depth for 3 weeks with salinity of 30 to 47% seawater and conductivity of 24,000 uS/cm. After pumping out seawater, site was flushed Grazing marsh (aquatic - East Anglia Cantley Marshes Ditches with freshwater and after 3rd flush conductivity was 2000-3000 uS/cm. English Nature Report RR629 (2006) ditches) Condutcivity levels fallen back to 1980s levels ~3.5 years after the flood. Majority of ditch endgroups degraded to eutrophic/brackish communities the year after flood (1994), but appeared to be recovering ~3 years later.

Purple moor grass and NVC tyes M22-M26 and National Relationship to salinity not assessed in a quantitative manner. Rodwell 1991 rush pasture MG10

Purple moor grass and Cley (part of North Based upon a flood event in Feb 1938, during which seawater was present for East Anglia Common rush English Nature Report RR629 (2006) rush pasture Norfolk Coast SAC) 3 months, the species died and took between 2 to 4 years to reappear

H:\Projects\Ea-210\24903 Coastal Biodiversity and Climate Change\Docs\Outputs - deliverables\D24iJOM_Sensitivity_criteria.xlsD24iJOM_Sensitivity_criteria.xls - Supporting evidence Page 1 of 2 Appendix F2

Corresponding BAP Habitat/ species described habitat Region Site/area in evidence Evidence of sensitivity to seawater inudation & recovery time Source Based upon a flood event in Feb 1938, during which seawater was present for Purple moor grass and Cley (part of North East Anglia Sedge 3 months, the species died and took 2 years to begin recovery but still much English Nature Report RR629 (2006) rush pasture Norfolk Coast SAC) affected

Based upon a flood event in Feb 1996, during which seawater was present for Purple moor grass and Cley (part of North East Anglia Grassland several weeks up to 2m deep, habitat recovered after 1 year but changes in English Nature Report RR629 (2006) rush pasture Norfolk Coast SAC) sward composition (greater prevalance of maritime grasses) was reported

Purple moor grass and North Wales Glas Lyn Marshes Rush pasture in dune slacks Site periodically inundated but seems to be little effect upon habitat Stuart Smith (grassland specialist, CCW) rush pasture

Infrequent inundation (severe storm event at 2, 5 or 10 year intervals) provided Purple moor grass and Washland grassland ('salty seawater disperses after a few days results in a semi-natural sward Flood Alleviation Strategy for Broadland East Anglia Broadland rush pasture grassland') composition. Salt tolerant/salt marsh species will dominate the sward where (NRA, 1992) seawater flooding occurs at 12 to 15 times per year

Purple moor grass and Salinity (conductivity) levels are 650-700 uS/cm reflecting lack of saline Coastal Squeeze and Maintenance of East Anglia Suffolk Coast Fen Meadow rush pasture intrusion Wetland (White Young Green, 2006)

Reed is able to thrive in brackish water. But intrusion of saltwater into Reedbed Management for Wildlife and Reedbed National - Reedbed freshwater reedbeds can be detrimental, causing die-back which can take Commercial Interest (RSPB, 1996) several years to recover from.

Porlock Ridge and Flood defences breached in Jan/Feb 1990 and seawater was present for up to Saltmarsh, part of the 3 months resulting in almost complete 'kill' of all vegetation in the SSSI Sue Rees (Natural England Coastal Reedbed South west site was formerly Reedbed (brackish) (brackish, brackish lagoon surrounded by saltmarsh, some alder carr, semi- Specialist) - perscomms 2009 Porlock Marsh improved and improved grassland). By May 1991, most of the SSSI, and it is (Somerset) assumed this included reedbed had reestablished

Feb 1996 flood event and water remained for 4 weeks at 2m depth but Cley (part of North Reedbed East Anglia Reedbed recovered. Recovery time for future similar events predicted to be 3 to 10 English Nature Report RR629 (2006) Norfolk Coast SAC) years. Flooded in 1976 and 1995. Recovery of the site was rapid on both occassions Burnham Overy Staithe (several months), but future recovery predicted to be from several months, to 5 Reedbed East Anglia Reedbed English Nature Report RR629 (2006) (North Norfolk Coast) years, even up to 10 years if flooded to 0.5m depth for several weeks and not flushed

Cley (part of North Following the Feb 1996 flood, reed growth was poor in the 1996 growing Bernard Bishop (Norfolk Wilsdlife Trust Reedbed East Anglia Reed Norfolk Coast SAC) season but reed is now in good condition. Reserve Warden) - perscomms 2009

Site flooded regularly in 1940s, flooded in 1953, flooded regularly in 1970s and Cley (part of North 1980s and in Feb 1996 there was 2m depth of sea water present for at least a Bernard Bishop (Norfolk Wilsdlife Trust Reedbed East Anglia Reedbed Norfolk Coast SAC) month. Despite this the site is still considered to be in good condition, albeit Reserve Warden) - perscomms 2009 some areas of the site are a bit more brackish than before.

Based upon a flood event in Feb 1938, during which seawater was present for Cley (part of North 3 months, reed survived inundation but took 2 years after flood before normal Reedbed East Anglia Reed English Nature Report RR629 (2006) Norfolk Coast SAC) growth resumed, but in some areas (the low marshes closer to the sea?) reed growth still poor North Norfolk Coast Examples of regularly inundated habitats occur at this site and these habitats Roger Morris (formerly Natural England) - Reedbed East Anglia Reedbed SAC are more robust than we think perscomms 2009 Site chronically affected by increased salinity (presuambly from increased Andrea Kelly (Broads Authority) - Reedbed East Anglia Upper Thurne Reedbed inundation?) perscomms 2009

Easton Broad (Benacre Reedbed East Anglia Reedbed Historically this was breached regularly, less so now. Reedbed still present Adam Burrows (Natural England) & Easton Bavents SAC)

Benacre (Benacre & Reedbed dying back (presumably from increased inundation) and site more Reedbed East Anglia Reedbed Adam Burrows (Natural England) Easton Bavents SAC) saline in the last 12-15 years than historically

Reedbed (S4 swamp) indicative of mildly brackish conditions/saline intrusion Coastal Squeeze and Maintenance of Reedbed East Anglia Suffolk Coast Reedbed with salinity ranges of 800-2000 uS/cm. Wetland (White Young Green, 2006)

Porlock Ridge and Flood defences breached in Jan/Feb 1990 and seawater was present for up to Saltmarsh, part of the 3 months resulting in almost complete 'kill' of all vegetation in the SSSI Sue Rees (Natural England Coastal Saline lagoons South west site was formerly Saline lagoons (brackish, brackish lagoon surrounded by saltmarsh, some alder carr, semi- Specialist) - perscomms 2009 Porlock Marsh improved and improved grassland). By May 1991, most of the SSSI, which it (Somerset) is assumed includes the saline laggon habitat had reestablished

Cley (part of North 1996 flood event water remained for 4 weeks at 2m depth. Recovery time for Saline lagoons East Anglia Brackish open water English Nature Report RR629 (2006) Norfolk Coast SAC) future similar events predicted to be <2 years.

Salinities should be in the range 15%-40% (35% is considered to be seawater salinity), and should only be outside these ranges for several days at most not several weeks, otherwise an effect will occur. Salinities of ~35% occur where Saline Lagoons A Guide to their Saline lagoons National - Saline lagoons lagoons exchange lagoon water on most tides (e.g. some of the biodiversity Management and Creation (Bamber et al , rich lagoons exchange 35-50% of their water on each tide). Lagoons sensitive 2001) to excessive salinity during summer/autumn due to high rates of evaporation and low rainfall.

Variation outside the preferred salinity range of 15-40% will damage interest A Practical Guide to the Management of Saline lagoons National - Saline lagoons features if it persists for more than a few days Saline Lagoons (RSPB, 2004) Although W5 is described as as occurring where there are tidally-related water NVC types W1, W2, W4, Wet Woodland National fluctuations, no mention of tolerance to saline flooding is given for this or other Rodwell 1991 W5, W6 wet woodland communities

Porlock Ridge and Flood defences breached in Jan/Feb 1990 and seawater was present for up to Saltmarsh, part of the 3 months resulting in almost complete 'kill' of all vegetation in the SSSI Sue Rees (Natural England Coastal Wet woodland South west site was formerly Alder carr (brackish, brackish lagoon surrounded by saltmarsh, some alder carr, semi- Specialist) - perscomms 2009 Porlock Marsh improved and improved grassland). By May 1991, most of the SSSI, which it (Somerset) is assumed includes the alder carr had reestablished

Based upon a flood event in Feb 1938, during which seawater was present for 3 months, ash, alder, willow, horse chestnut and conifer were all killed. Some Cley (part of North survival of poplar and oak particularly young trees. Silver birch relatively Wet woodland East Anglia Trees English Nature Report RR629 (2006) Norfolk Coast SAC) resistant and this species along with horse chestnut survived the flood and took 3 years to recover. Willow - replanted but still many replanted trees died and took 4 years to recover

Salinity (conductivity) levels are 650-700 uS/cm reflecting lack of saline Coastal Squeeze and Maintenance of Wet woodland East Anglia Suffolk Coast Wet woodland intrusion Wetland (White Young Green, 2006)

Notes >450 tidal inundations per year will result in the development of mudflat; between 300 and 450 pioneer saltmarsh, <300 low marsh and upper marsh (RSPB, 2005)

Salt build up in soil exascerbates recovery time (Bernard Bishop, NWT;English Nature Report RR629) Salt prevalance exascerbated by low rainfall following inundation (English Nature Report RR629) Peat wetness at the time of inundation may be important in preventing salt build up - habitat seems to be ok if peat is already saturated with freshwater (Clive Doarks, Natural England) Inundation in late autumn may be ok but inundation in spring means the effects are worse (presumably because spring is the growing season) (Bernard Bishop, NWT) Flushing flows by spring discharges help dilute salinity and enable quicker recovery (Bernard Bishop, NWT) Extent of damage depends upon how quickly the seawater can be drained/pumped off (based upon evidence provided by Matt Bradbury, NWT; English Nature Research Report RR629) Winter flooding is less damaging than summer flooding (presumably because summer flooding is during the growing season, freshwater flushing/dilution from rainfall is less likely) (NRA, 1992) All wetland habitats (reedbed, swamp, tall herb fen, fen meadow, wet woodland, wet grassland) sensitive to saline intusion - typical values in the habitats are 650-700 uS/cm reflecting lack of saline intrusion, and for reedbed 800-2000 suggesting some maritime influence. During extreme storm events salinity goes up to 45,000 uS/cm temporarily (WYG, 2006) Brackish ditches have conductivity of mean 7860 uS/cm and freshwater ditches mean 1815 uS/cm (ADAS, 1997), brackish waterbodies mean 20,000 uS/cm, freshwater coastal ones mean 434 uS/cm (JNCC, 2006) 5% salinity is considred to be 'fresh' at coastal locations, and 35% salinity is considered to be seawater salinity (Bamber et al 2001). Estuarine water is less than 35% (RSPB, 2004)

4000 uS/cm = 2ppt 24000uS/cm=13ppt

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Appendix G Details of the Workshop

A workshop held on 25 January 2010 was attended by a cross-section of invited experts in the requirements of BAP habitats. The main objective of the workshop was to develop matrices describing the sensitivity of the priority BAP habitat considered in this study to saline flooding. Workshop materials comprised a short note providing background information (see Appendix G1) and pre-filled draft matrices.

Importantly, the participants engaged with the proposed approach of using sensitivity matrices to inform the modelling of potential habitat losses resulting from a range of sea-level rise scenarios. The output from the workshop was a series of sensitivity matrices, which the experts agreed, appropriately reflected the sensitivities of the BAP habitats to the range of possible flood events indicated in the matrix template.

Appendix G1 Workshop Materials Circulated in Advance

Developing Tools to Evaluate the Consequences for Biodiversity of Options for Coastal Zone Adaptation to Climate Change

Biodiversity Action Plan (BAP) Habitat Sensitivity and Categorisation of Ease of Habitat Creation Workshop

Entec, HR Wallingford and CEH are working on a project for Defra and Natural England that is aiming to quantify the risks to specific open-water and wetland BAP habitats from saline inundation caused by sea level rise due to climate change. This project is focusing on the effects of inundation with brackish/saline waters1 on BAP habitats behind the natural and defended coastline. The project outputs will provide Natural England and Defra with a more quantitative estimate of habitat creation and climate change adaptation requirements into the future in order to meet national BAP targets.

Two of the key interim outputs from the project will be:

1) An analysis of the sensitivity of habitats to potential increases in brackish/saline flooding events and mapping of risk of habitat loss.

2) A ranking of the ease of creation of the habitats, in the event that replacement is necessary.

As experts in the ecohydrological requirements of these habitats we need your help to develop an analysis of habitat sensitivity to brackish/saline flooding and the resulting rules, and to develop both a method for ranking ease of creation and the ranking itself.

To facilitate this a workshop has been arranged to take place on 22nd January 2010 at Natural England, Ashdown House, 123 Victoria Street. London. SW1E 6DE. The workshop will commence at 10am, with coffee from 9.30am.

Please note that if you find you are unable to make the workshop we would still value your inputs to the sensitivity matrices and habitat creatability criteria. Please send comments/inputs to Andy Brooks ([email protected]) and Gordon Glasgow ([email protected]). Additionally, if you have any questions in advance of the workshop, please contact Andy Brooks in the first instance.

Development of Sensitivity Criteria

The project is using a national flood risk assessment approach to look at the impacts of coastal flooding conditions under climate change scenarios. To inform the model assessment of risk to the BAP habitats we need to produce a set of ‘sensitivity matrices’ – one for each of the habitats in the study (apart from CFGM which will have two: one for the grassland and one for the ditches). These matrices need to reflect the likely response of each habitat to the frequency and duration of saline flooding, and will be used to quantify risk.

The sensitivity matrices are required to express the anticipated probability of loss of habitat, given a particular combination of flood frequency and duration. It is recognised that there may be significant uncertainty associated with the probability estimates.

Example matrices are presented below in Figure 1 and 2.

1 There is a parallel Environment Agency project ‘The Environmental Consequences of Flooding’ that is considering the effects of freshwater flooding of freshwater BAP habitats)

Figure 1: Blank Sensitivity Matrix

Figure 2: Sample Completed Sensitivity Matrix

An expert assessment of the relative likelihood of loss is required for each cell of the matrix (for each BAP habitat). There are several possible definitions of ‘loss’ including significant change in vegetation composition, loss of ecological functionality and complete change in habitat type/complete loss and these can be recoverable or unrecoverable conditions. In this study we are using complete change in habitat type/complete unrecoverable loss as the definition2.

A Microsoft Excel Spreadsheet (BAPHabitat.xls) has been prepared to supplement this introduction and is circulated with this pre-workshop information. The spreadsheet contains additional background information and pre-prepared matrices based on our analysis of the probability of complete habitat loss. During the workshop we would like you to amend these matrices with your knowledge of the specific habitats.

Wherever possible, any evidence or experience that has been used as a basis for judgement should be brought to and/or communicated through the workshop.

As it is important that attendees are able to amend the sensitivity matrices during the workshop, it is highly recommended that you familiarise yourself with these, or even amend these, prior to arrival. Please note that the spreadsheet will autosave amendments to the matrices. Any completed matrices can be returned to [email protected] and [email protected], and they will be used to supplement the information gathered through the workshop.

2 Please note that we are not predicting what the habitat will change to. Example output that would be produced using the matrices and modelled scenarios is presented in Figure 3 below.

Figure 3: Sample Mapping of Habitat Risk

There are limitations in the flood risk modelling and the key assumptions we are making are:

• Flushing with freshwater is a key component to the support of the habitats on many sites in coastal areas and will significantly influence the impacts of any inundation with brackish/saline water to habitats. The modelling cannot however predict the presence and effects of flushing with freshwater. The matrices that you derive will implicitly consider the effects of flushing because they will probably be based on observations from sites that experience flushing. Please could delegates comment on this when completing the matrices.

• Salinity gradients exist across many freshwater sites in coastal environments that affect how a habitat reacts to inundation with brackish/salt water. Modelling cannot take this into account although we can comment on this in the reporting phase. Please could delegates comment on this when completing the matrices.

• There will be variations in the salinity of water that inundate sites, depending on the location of the site relative to the coast. For the purposes of the analysis however we will assume that the inundation is with undiluted sea water.

Ranking of the ease of creation of the BAP habitats

As part of this project we have been asked to develop a ranking of the ease of habitat creation and have developed a series of scoring criteria to do this. The criteria are also circulated within this pre- workshop information pack (D23i4_Habitat_creatibility_tool.xls).

At the workshop you will be asked how this could/should be amended. Therefore please familiarise yourselves with the criteria in advance to enable you to suggest amendments on the day.

Thank you and see you there. The Project Team January 2010 Ease of implementation Parameters Criteria Options Ease of implementation scoring (qualitative) scoring (quantitative) In general, successful creation…. 1 Timescales …requires the following timescales A 5-9 years Achievable on a short (project/management plan) timescale 1 B 10-50 years Achievable on a medium (human 'generation') timescale 2 C 50-100s of years Achievable in a longer (several human 'generations') timescale 5 2 Size (ha) (min.extent) …requires the following minimum area to be ecologically functional A <2ha Achievable with minimum land acquisition 1

(Functional = habitat supports the key characterisitc botanical species, undergoing appropriate natural processes for the habitat e.g. peat acumulation for bogs, able to support typical fauna of that habitat) B 2 to 9 ha Achievable with a small amount of land acquisition 2 C 10-99ha Achievable with a greater extent of land acquisition 5 D 100+ Achievable with extensive land acquisition 15

3 Method of creation …requires the following method of creation A Abandonment of current land use only Achievable with minimum involvement/intervention 1 B Limited land preparation and no/only small-scale engineering/water control Achievable with a greater level of involvement/engineering 2 C Extensive land preparation, significant engineering/water control Achievable with extensive involvement/enginering 5

Tolerates a highly variable or not particularly exacting water regime year round (e.g. tolerates water table several 10s of centimetres below ground level to occasional inundation. Habitats needing standing water - wide variation acceptable relative to water body depth), groundwater Probably achievable with minimum involvement/intervention/management of 4 Hydrological regime …requires/tolerates the following hydrological regime A not specifically required regime 1 Able to tolerate less water table variation / requires more exacting regime (e.g. does not require water table at the surface, tolerates water table around 10-20 centimetres below ground level with specific seasonal requirements. Habitats needing standing water - moderate variation in water depth tolerated relative to water body depth), some groundwater Probably achievable with a greater level of B input required involvement/engineering/management of regime 2

Requires an exacting regime where the water table is at or near (within a few centimetres) the ground surface all year. Habitats needing standing water unable to tolerate variation of more C than a few cm. Significant groundwater input required to maintain the habitat Probably requires extensive involvement/engineering/management of regime 5 5 Trophic status …requires/tolerates the following trophic status A Eutrophic Requires water sources widely available 1 B Eutrophic/mesotrophic Requires water sources less widely available 2 C Mesotrophic Requires water sources with restricted availability 5 D Oligotrophic Requires water sources with very restricted availability 15 6 Substrate availability …requires substrate which A is abundant/widely distributed nationally Substrate is abundant/widely distributed nationally 1 Substrate is generally less abundant/has a more restricted distribution B generally is less abundant/has a more restricted distribution nationality nationality 2

C generally is not abundant/ has a localised distribution nationally Substarte is generally not abundant/ has a localised distribution nationally 5 7 Source of biological material …requires the following source of biological material A Natural succession Achievable with minimum involvement/landscaping 1 B Initial seeding Achievable with a greater level of involvement/landscaping 2 C Involved extensive planting/seeding Achievable with extensive involvement/landscaping 5 8 Management …requires the following management A Low intensity management (every 5 years or greater) Achievable with minimum involvement/management 1 B Moderate intensity management (every 2 years or so) Achievable with a greater level of involvement/management 2 C Continuous/intensive (annual) management Achievable with extensive involvement/management 5

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Appendix H Ease of Habitat Creation Scoring Approach and Ranking Analysis

Table H.1 Criteria and scoring used to rank habitats in order of ease of creation

Parameter Criteria Options Ease of Implementation Scoring (Qualitative) Ease of Implementation In general, successful creation…. Scoring (Quantitative)

Timescales …requires the following timescales A 5-9 years Achievable on a short (project/management plan) timescale 1

B 10-50 years Achievable on a medium (human 'generation') timescale 2

C 50-100s of years Achievable in a longer (several human 'generations') timescale 5

Size (ha) (min. extent) …requires the following minimum area to be A <2ha Achievable with minimum land acquisition 1 ecologically functional

B 2 to 9ha Achievable with a small amount of land acquisition 2

C 10-99ha Achievable with a greater extent of land acquisition 5

Method of creation-recreation …requires the following method of creation A Abandonment of current land use only Achievable with minimum involvement/intervention 1

B Limited land preparation and no/only small-scale engineering/water control Achievable with a greater level of involvement/engineering 2

C Extensive land preparation, significant engineering/water control Achievable with extensive involvement/engineering 5

Hydrological regime …requires/tolerates the following hydrological A Tolerates a highly variable or not particularly exacting water regime year round (e.g. Probably achievable with minimum involvement/intervention/management of regime 1 regime tolerates water table several 10s of centimetres below ground level to occasional inundation. Habitats needing standing water - wide variation acceptable relative to water body depth), groundwater not specifically required

B Able to tolerate less water table variation / requires more exacting regime (e.g. does not Probably achievable with a greater level of involvement/engineering/management of 2 require water table at the surface, tolerates water table around 10-20 centimetres below regime ground level with specific seasonal requirements. Habitats needing standing water - moderate variation in water depth tolerated relative to water body depth), some groundwater input required

C Requires an exacting regime where the water table is at or near (within a few centimetres) Probably requires extensive involvement/engineering/management of regime 5 the ground surface all year. Habitats needing standing water unable to tolerate variation of more than a few cm. Significant groundwater input required to maintain the habitat

Trophic status …requires/tolerates the following trophic status A Eutrophic Requires water sources widely available 1

B Eutrophic/mesotrophic Requires water sources less widely available 2

C Mesotrophic Requires water sources with restricted availability 5

D Oligotrophic Requires water sources with very restricted availability 15

Substrate availability …requires substrate which A Is abundant/widely distributed nationally Substrate is abundant/widely distributed nationally 1

B Generally is less abundant/has a more restricted distribution nationality Substrate is generally less abundant/has a more restricted distribution nationally 2

C Generally is not abundant/ has a localised distribution nationally Substrate is generally not abundant/ has a localised distribution nationally 5

Source of biological material …requires the following source of biological A Natural succession Achievable with minimum involvement/landscaping 1 material

B Initial seeding Achievable with a greater level of involvement/landscaping 2

C Involved extensive planting/seeding Achievable with extensive involvement/landscaping 5

Management …requires the following management A Low intensity management (every 5 years or greater) Achievable with minimum involvement/management 1

B Moderate intensity management (every 2 years or so) Achievable with a greater level of involvement/management 2

C Continuous/intensive (annual) management Achievable with extensive involvement/management 3

Table H.2 Results of the scoring and ranking exercise

Coastal and Floodplain Eutrophic Standing Water Fen Lowland Raised Bog Purple moor grass and Reedbed Saline lagoons Wet woodland Grazing Marsh (lakes and ponds) rush pasture

Option Score Option Score Option Score Option Score Option Score Option Score Option r Score Option Score

Timescales A 1 A 1 B 2 C 5 A 1 A 1 A 1 B 2

Size (ha) (min. extent) B 2 A 1 C 5 C 5 B 2 B 2 A 1 B 2

Method of creation B 2 B 2 C 5 C 5 B 2 B 2 B 2 A 1

Hydrological regime B 2 A 1 C 5 C 5 B 2 A 1 B 2 B 2

Trophic status B 2 A 1 B 2 D 15 C 5 B 2 C 5 B 2

Substrate availability A 1 A 1 C 5 C 5 A 1 B 2 A 1 A 1

Source of biological material B 2 B 2 B 2 B 2 B 2 B 2 A 1 C 5

Management C 5 A 1 B 2 A 1 C 5 B 2 A 1 A 1

Score 17 10 28 43 20 14 14 16

All scores are out of a maximum of 50. Ponds and lakes have not been separated in the scoring exercise. The only difference would be in the score for minimum size, where lakes would have a B (scoring 2). The ease of creating wet woodland has been assessed despite the use of a composite deciduous woodland BAP inventory in the risk analyses.

Appendix I Summary Evidence and References Supporting the Scoring Decisions

Timescales

Habitat Creation timescales Ref. Option Rationale/comments Coastal and Floodplain Grazing Marsh Several years 4 A Grassland (ditches included in eutrophic standing water) Restored grazing marsh grassland has been created at numerous sites around the English coast, with some success in terms of habitat structure and ability to support wetland birds. The time span required for the lowland wet grassland that forms a component of the grazing marsh landscape may be allocated to Option B IF botanically-rich swards are the objective

Eutrophic standing waters Several years 1 and 3 A Ponds/ditches (including those within a grazing marsh landscape) Numerous examples both of ditch creation in grazing marshes and of pond creation (e.g. http://www.pondconservation.org.uk/) exist, where acceptable results have been created in <10 years

Fen Several decades B Some variants of fen habitat may be created in a relatively short time, especially where the fen is essentially a modified reedbed with a larger forb component or where lowland wet grassland is subject to less frequent cutting and grazing. However, for more complex fen habitats with peat development, the evidence from sites such as the Great Fen and the Wicken Vision is that a period of at least a decade is necessary to give any semblance of true fen (see lowland raised bog)

Lowland raised bog At least several decades 5 C Based upon experience at Thorne and Hatfield Palaeoecological evidence and natural recolonisation of cutover raised bogs (e.g. within the Brue valley of Somerset) shows that lowland raised bogs frequently develop through an intermediate seral stage of fen, consistent with allocation of the fen and bog to timescale options B and C respectively

Purple moor grass and rush pasture Several years 1, 6, 7 A Rush pasture/fen created at landfill site Other examples of creating Molinia-Juncus habitat suggest somewhat longer timescales, especially where the measure of success in comparison with high-grade habitat (e.g. NVC type M24)

Reedbed Several years 8, 9, 10 A Reed grows rapidly Numerous examples of reed-bed creation in shallow lagoons, abandoned peat-diggings etc . Some experimental work using either rhizome fragments or from seed. See sources and also http://www.rspb.org.uk/ourwork/conservation/managingreserves/ha bitats/reedbeds/reedbedcreation.asp

Saline lagoons Several years A

Wet woodland 5-13 years to establish 1, 11 B May take up to 40 years if rely on natural succession

References 1 Ecoscope Applied Ecologists (2000) Wildlife Management and Habitat Creation on Landfill Sites 2 Pers.comms with Tim Kohler Natural England 3 Gilbert and Anderson (1998) Habitat Creation and Repair 4 Parker (1995) Habitat Creation a Critical Guide 5 Sutherland and Hill (2005) Managing Habitats for Conservation 6 Adams, W.A., Roughley, G., Young, R.J., (1999). An experimental study to re-establish Molinia–Juncus pasture from improved grassland at Rhos Llawr-cwrt National Nature Reserve. Countryside Council for Wales Contract Science Report No. 355, Bangor. 7 Tallowin, J.R.B., Smith, R.E.N., 2001. Restoration of a Cirsio–Molinietum fen-meadow on an agriculturally improved pasture. Restoration Ecology 9, 167–178. Fermor, P.M., Hedges, P.D., Gilbert, J.C. and Gowing, D.J.G. (2001). Reedbed evapo-transpiration rates in England. 8 Hydrological Processes , 15: 621-631 Gilman, K., Hudson, J.A. and Crane, S.B. (1998). 9 Hydrological evaluation of reedbed re-creation at Ham Wall Somerset. Report to Somerset County Council, RSPB & English Nature. EU Life Project 92-1/UK/026 Hawke, C.J. and José, P.V. (1996). . Sandy: Royal Society 10 Reedbed management for commercial and wildlife interests for the Protection of Birds. R., Gonzáles del Tánago, M., and Mountford, J.O. (In press). Restoring floodplain forests in Europe. Book chapter (#18) 11 in: In P. Madsen, P., Stanturf, J. (eds.). A Goal-Oriented Approach to Forest Landscape Restoration. Springer

Size

Habitat Min. creation size Ref. Option Rationale/comments Coastal and Floodplain Grazing Marsh 2-5 ha 2 B To support wetland birds Smaller areas might be viable for vegetation and invertebrates

Eutrophic standing waters 100m2 1 A Minimum size for great crested newt Again smaller areas may be viable for vegetation and invertebrates, and less mobile vertebrates (e.g . smaller fish)

Tens to hundreds Fen 4, 5 C Estimation of area required based upon tall-herb rich fen ( types of hectares NVC S24 etc ) - the main type of this habitat in landscapes vulnerable to saline floods. Where the fen supports or is intended to support "landscape species" (ref. 5) then larger areas of habitat should be considered as the minimum viable

Viable areas of raised mire may be as little as 1 ha in extent but only Tens to hundreds where buffered by larger areas of degraded habitat and Lowland raised bog 6C of hectares isolated/distinct areas of raised mire are normally well in excess of 50 ha

Purple moor grass and rush pasture Several hectares B Individual fields of this habitat may be as small as 2 ha extent, but tend to occur in complexes were several adjacent fields support this habitat

Reedbed At least 2 ha 2 and 3 B 20 ha to support bittern et al Since the primary conservation value of this habitat lies with the animals (especially vertebrates) that it supports, estimates of minimum creation size for reedbed should be based on the requirements of such "landscape species"

Saline lagoons <2ha A

Wet woodland at least 5 ha 1 B Although areas as small as 1 ha are defined as woodland under agri-environment schemes, the functional habitat (together with its characteristic vertebrates) requires a bare minimum of 5 ha References 1 Ecoscope Applied Ecologists (2000) Wildlife Management and Habitat Creation on Landfill Sites 2 Parker (1995) Habitat Creation a Critical Guide 3 Sutherland and Hill (2005) Managing Habitats for Conservation WCS (2001) The Landscape species approach- a tool for site-based conservation. 4 Wildlife Conservation Society Living Landscapes Program Bulletin 2: 1-4. Hughes, F.M.R., Stroh, P., Mountford, J.O., Warrington, S., Gerrard, C. & Jose, P. (2008) Monitoring large-scale wetland restoration projects: Is there an end in sight? in P. Carey (ed.) Landscape Ecology and Conservation. 5 Proceedings of the 15th Annual Conference of the International Association for Landscape Ecology (UK Chapter), Cambridge, UK, September 8-11th , 2008 p.170-179. 6 Bragg, O.M., Lindsay, R.A., Robertson et al (1984). An historical survey of lowland raised mires, Great Britain. Nature Conservancy Council

Creation Method

Habitat Creation Method Ref. Option Rationale/comments Coastal and Floodplain Grazing Marsh 1, 3, 4 B Likely for some preparation to be needed (e.g. appropriate seed mix, irregular topography, some water control)

Eutrophic standing waters 1 B Hole needs to be dug for water body or ditch as a minimum

Fen 2, 5 C As for bog

Lowland raised bog Very involved 2 C Based upon re-wetting of lowland raised bog at Thorne & Hatfield (pers.comms Tim Kohler Natural England)

Purple moor grass and rush pasture B Natural successional process following abandonment is for habitat to become more rank. Some land preparation and seeding likely to be needed

Reedbed 1 B Reed will readily colonise unaided if right conditions persist and reed is already present. However some ground preparation and plug planting likely to be necessary. Hence option B selected.

Saline lagoons 1 B Hole needs to be dug for lagoon as a minimum

Wet woodland 1 A Natural successional process following abandonment is for habitat to scrub over References 1 Gilbert and Anderson (1998) Habitat Creation and Repair 2 Parker (1995) Habitat Creation a Critical Guide Benstead, P., Drake, M, José, P, Mountford, O., Newbold, C. and Treweek, J. 1997. The Wet Grassland Guide. 3 Sandy: Royal Society for the Protection of Birds.

Manchester, S.J (Unpublished). The potential for the restoration of lowland wet grassland upon ex-arable land. 4 Unpublished Ph.D. thesis, Oxford Brookes University, Oxford. 5 McBride, A., Diack, I., Droy, N., Hamill, B., Jones, P., Schutten, J., Skinner, A. and Street, M. (2010). The Fen Management Handbook. Scottish Natural Heritage. Perth [see Chapter 9 on Creating Fen Habitat]

Hydrology

Habitat Regime Ref. Option MG8 tolerates summer water table several tens of centimetres Coastal and Floodplain Grazing Marsh below ground and occasional inundation 1B

Typically composed of free floating species able to tolerate fluctuations, and even temporary drying out provided substrate Eutrophic standing waters remains damp 1A

S24e supports most rare species and requires water table at or Fen near surface most of the year 1C

Lowland raised bog Pristine bogs have a water table at or near the surface 4C

M24 tolerates summer water table several tens of centimetres Purple moor grass and rush pasture below ground and occasional inundation 1B

Reedbed S4 tolerates a regime from 0.5m agl to 0.15 bgl 1A

Able to tolerate a reasonable amount of fluctuation in water levels Saline lagoons provided salinity ranges are maintained 3B

Other S24 communities tolerates summer water table several tens Wet woodland of centimetres below ground and occasional inundation 1B

Notes Swamp (S24) communities used as surrogates for fen communities based upon workshop outcomes Fen used as surrogate for wet woodland because the main interest with wet woodland is the ground flora which resembles swamp/fen Barsoum et al - no readily usable quantitative evidence

Trophic Requirements

Habitat Trophic status Ref. Option Rationale/comments Coastal and Floodplain Grazing Marsh Mesotrophic B &/or C Option depends on the grassland type - MG8 is more C than B (which would be appropriate for MG13, MG11 and other grazing marsh swards)

Mesotrophic to Eutrophic standing waters eutrophic 1A

S24 communities - mesotrophic to Fen eutrophic 1, 5 B

Lowland raised bog Oligotrophic 4D

M24 - oligotrophic to Purple moor grass and rush pasture mesotrophic 1C

S4 occurs in oligotrophic to Reedbed eutrophic conditions 1 B B as a compromise

Eutrophication is a Saline lagoons threat 3C

S24 communities - mesotrophic to Wet woodland eutrophic 1B

References 1 Wheeler et al (2004) Ecohydrological Guidelines for Lowland Wetland Plant Communities 2 Barsoum et al (2005) Ecohydrological Guidelines for Wet Woodland - Phase 1 3 Bamber et al (2001) Saline Lagoons: A Guide to Their Management and Creation 4 Stoneman and Brooks (1997) Conserving Bogs The Management Handbook 5 McBride, A., Diack, I., Droy, N., Hamill, B., Jones, P., Schutten, J., Skinner, A. and Street, M. (2010). The Fen Management Handbook. Scottish Natural Heritage. Perth [see Chapter 9 on Creating Fen Habitat] Notes Swamp (S24) communities used as surrogates for fen communities based upon workshop outcomes Fen used as surrogate for wet woodland because the main interest with wet woodland is the ground flora which resembles swamp/fen Barsoum et al - no readily usable quantitative evidence

Substrate Requirements

National Coverage Soilscape (England) (%) Texture Habitats Corresponding UK BAP Habitat Rationale Water 0.4 - -- Sub-total 0.4

Base rich pasture and ancient woodlands, lime rich flush vegetation in wetter Fen, grazing marsh, rush pasture, Lime rich loams and clays impeded 5.3 Clayey areas wet woodland, reedbed Sub-total 5.3

Saltmarsh not within the scope of Saltmarsh soils 0.2 Loamy Coastal salt marsh - the study Limestone pastures, pavements and lime rich deciduous Shallow lime rich soils over chalk or 7 Loamy woodlands Grazing marsh, rush pasture Limestone pastures, Free draining would infer that and lime rich deciduous terrestrialised wetland habitat Freely draining lime rich loamy soils 3.7 Loamy woodlands ? would not prevail Neutral and acid pastures, bracken, Free draining would infer that gorse, deciduous terrestrialised wetland habitat Freely draining slightly acid loamy so 15.5 Loamy woodlands - would not prevail Free draining would infer that Base rich pasture and terrestrialised wetland habitat Freely draining slightly acid but base 3.1 Loamy deciduous woodlands ? would not prevail

Wide range of pastures Grazing marsh, rush pasture, wet Slightly acid loams and clays impede 10.6 Loamy and woodlands woodland, reedbed

Grassland and wet carr Grazing marsh, rush pasture, wet Freely draining floodplain soils 0.6 Loamy in old river meanders woodland, reedbed Free draining would infer that Steep upland acid terrestrialised wetland habitat pastures, dry heath and would not prevail, and upland moor, bracken, gorse areas are not within the scope of Freely draining acid loamy soils over 2.6 Loamy and oak woodland - the study Seasonally wet pastures and Grazing marsh, rush pasture, wet Slow permeable seasonally wet acid 7 Loamy woodlands woodland Seasonally wet pastures and Grazing marsh, rush pasture, wet Slow permeable seasonally wet basi 19.9 Loamy woodlands woodland Wet meadows and wet carr in old river Grazing marsh, rush pasture, wet Naturally wet loamy and clayey flood 2.6 Loamy meanders woodland, reedbed Wet brackish coastal Naturally wet loamy and clayey soils 3.7 Loamy flooded meadows Grazing marsh, rush pasture Wet acid meadows and These habitats are not within the Naturally wet loamy soils 1.7 Loamy woodlands - scope of the study These habitats are not within the Restored soils mostly from quarry or 0.4 Loamy Variable - scope of the study Sub-total 78.6

Wet heather, grass Shallow very acid peaty soils over ro 0.4 Peaty moor, bog Lowland raised bog Grass moor and heather moor, flush Upland areas not within the scope Very acid loamy upland soils wet pea 1.6 Peaty and bog - of the study Grass moor and heather moor, flush Upland areas not within the scope Peaty slowly permeable wet very aci 2.9 Peaty and bog - of the study Naturally wet peaty loamy and sandy 1.5 Peaty Wet meadows Grazing marsh, rush pasture Wet heather moor with This habitat is not within the scope Blanket bog peat soils 2.1 Peaty flush and bog - of the study Raised bog peat soils 0.3 Peaty Raised bog Lowland raised bog Fen peat soils 0.7 Peaty Wet fen and carr Fen, wet woodland, reedbed Sub-total 9.5

This habitat is not within the scope Sand dune soils 0.2 Sandy Sand dune vegetation - of the study

Acid dry pastures, acid deciduous and Free draining would infer that coniferous woodland, terrestrialised wetland habitat Freely draining slightly acid sandy so 2.8 Sandy lowland dry heath - would not prevail Free draining would infer that terrestrialised wetland habitat Freely draining slightly acid Brecklan 0.3 Sandy Breckland heathland - would not prevail Free draining would infer that terrestrialised wetland habitat Freely draining very acid sandy and 1 Sandy Lowland dry heath - would not prevail Mixed dry and wet This habitat is not within the scope Naturally wet very acid sandy and loa 1.9 Sandy lowland heath - of the study Sub-total 6.2

TOTALS 100

Notes Data taken from National Soil Research Institute at Cranfield University http://www.landis.org.uk/soilscapes/ It is assumed that texture is a surrogate for a 'high-level' categorisation of the various soil types Reedbed habitat is not mentioned in the Cranfield data and therefore reedbed has been allocated to soil types where wet woodland or fen may occur on peats, clay soils wi Caveat - the data is a national view not a coastal view

% of England soil resource available for the habitat Coastal and Floodplain Grazing Mar 58.2 Fen 6 Lowland raised bog 0.7 Molinia meadows and rush pasture 58.2 Reedbed 19.8 Wet woodland 46.7 Eutrophic standing waters N/A* Saline lagoons N/A*

N/A*: Substrate is not critical as artificial materials could be used

Rank Creatibility category Coastal and Floodplain Grazing Mar 58.2 1 A Eutrophic standing waters N/A* 1 A Fen 6.0 4 C Lowland raised bog 0.7 5 C Purple moor grass and rush pasture 58.2 1 A Reedbed 19.8 3 B Saline lagoons N/A* 1 A Wet woodland 46.7 2 A

Source of Biological Materials

Habitat Material source Ref. Option Rationale/comments Coastal and Floodplain Grazing Marsh 1 and 2 B Initial seeding/other propagules to kick start creation

Eutrophic standing waters B Initial seeding/other propagules to kick start creation

Fen B Initial seeding/other propagules to kick start creation

Lowland raised bog B Initial seeding/other propagules to kick start creation

Purple moor grass and rush pasture 1 and 2 B Initial seeding/other propagules to kick start creation

Reedbed 1 B Reed will readily colonise unaided if right conditions persist and reed is already present, however see comment below. As a result option B has been selected.

Saline lagoons A Characteristic species will readily colonise on the next tide if right conditions persist

Wet woodland C Can be achieved by abandonement but extensive planting/seeding may be needed to achieve cover on reasonable timescales References 1 Gilbert and Anderson (1998) Habitat Creation and Repair

Comment: this criterion is absolutely dependent upon geographical context. The statement made for reedbeds could equally well be made for the other habitats WHERE the area for ecological creation lies directly adjacent to some area of intact habitat. In addition work by CEH [e.g . Mountford, J.O., Roy, D.B., Cooper, J.M., Manchester, S.J., Swetnam, R.D., Warman, E.A. and Treweek, J.R. (2006). Methods for targeting the restoration of grazing marsh and wet grassland communities at a national, regional and local scale. Journal for Nature Conservation 14: 46-66] used co-occurrence maps to assess local species pools for particular habitats/communities and hence the chance that a given community might develop naturally without seeding assuming that the edaphic and hydrological factors were suitable and the right management in place. Note therefore Option B may be a more likely scenario for reedbed creation.

Co-occurrence Map of NVC Community M24 Molinia caerulea-Cirsium dissectum Fen-Meadow

Note: Lighter colours indicate higher co-occurrence of species.

Management Requirements

Habitat Management Ref. Option Rationale/comments Coastal and Floodplain Grazing Marsh Annual cut/grazing necessary 1 C

Eutrophic standing waters Infrequent or none 4 A Unlikely to need vegetation management more frequent than every 5 years

Fen Bi-annual management 2 B Similar to reedbed, as considering tall herb fen.

Periodic sapling removal but little other management necessary of established Lowland raised bog habitat 4A

Purple moor grass and rush pasture Grazing or cutting necessary to maintain struct 4 C Annual management necessary to prevent developing into rank habitat.

Reedbed 2-4 year rotation. 1 and 2 B Frequency depends upon area and/or resources.

Bed-lowering/sluice replacement only every Saline lagoons few decades 3A

Wet woodland Coppicing/thinning every 5 years, otherwise no 1A

References 1 Ecoscope Applied Ecologists (2000) Wildlife Management and Habitat Creation on Landfill Sites 2 Sutherland and Hill (2005) Managing Habitats for Conservation 3 Bamber et al (2001) Saline Lagoons: A Guide to Their Management and Creation 4 Professional judgement

Appendix J1 NaFRA Model - Step-by Step Explanation

The national flood risk assessment (NaFRA)

Assessment of sources

NaFRA includes fluvial flooding as well as coastal flooding. In this project, only the coastal flooding source has been considered, which means that habitats within the 1 in 1000 year coastal floodplain have been considered. This includes the coastal floodplain in estuary locations where it extends up to the tidal limit, so includes the tidal and tidal-fluvial floodplains. The model takes data on offshore waves, tides and currents and propagates these onshore to determine water levels at the coast for given sea conditions. The coastal water level is referred to as the loading condition. The model uses information on the sea conditions from long term data records from offshore monitoring buoys. This gives model inputs of sea conditions for a range of return period events, from the 1 in 2 year event up to the 1 in 1000 year event. The model uses these inputs to calculate the coastal water levels associated with each of the return periods (there are 39 return periods in the model covering the following T-year return periods: 1, 2, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000; see Gouldby et al, 2008). The resulting coastal water levels are the source term loadings in the flood model.

Assessment of pathways

The behaviour of pathways under each coastal loading condition is assessed to understand how much water enters the floodplain. The pathways consist of the defences in the National Flood and Coastal Defence Database (NFCDD: a database owned and maintained by the Environment Agency) and the natural coastline. The NFCDD contains information on where defences are located, their crest height, the defence type (i.e. earth embankment, concrete seawall etc) and condition (based on the latest field inspection). Where there are no defences, the topographical characteristics of the natural coastline are represented by the digital terrain model (DTM).

The amount of water entering the floodplain for each water level condition along the coast is assessed as follows: a) In locations where there are no defences, the level of water is compared to the level of the land and if water levels exceed land levels then water spills into the floodplain. b) In locations where there are defences, two aspects of defence failure are considered: the overtopping of the defence if the water level exceeds the crest height and the breaching of the defence which may happen for water levels higher or lower than the crest height. The overtopping of defences is calculated by comparison of water level with defence crest level (which is related through comparison of the

standard of protection) and the breaching of defences is calculated through use of fragility curves (Gouldby et al., 2008).

Defence fragility curves give the probability of breach for a given water level. A large body of scientific research has considered the physical processes of defence breach, including different failure mechanisms and the relationship between defence failure and loading (water level) conditions. The failure of a defence is influenced by defence type and defence condition as well as the water level. Different defence types have different levels of strength and resilience to water level loads and there are, therefore, different fragility curves for different defence types. The defence condition is expressed as a ‘condition grade’ of 1 to 5, where condition grade 1 is the best condition a defence can be in and condition grade 5 is the worst condition a defence can be in. The likelihood of the defence being abandoned is not included within the model but the model scenarios that include degraded defences, assume defence condition deteriorates to grade 5. The condition grade of defences at present is given in the NFCDD based on the latest field inspection results. For a given defence type, there are also different fragility curves for each condition grade. There are over 600 fragility curves that have been developed and an example of a set of fragility curves for a sea wall is given in Chart J.1.

Chart J.1 Defence fragility curves for a narrow concrete vertical sea wall

1.0

0.9 0.8

0.7

0.6

0.5 0.4

0.3 Probability of failure of Probability 0.2 0.1

0.0 00.511.522.53

Water level - Crest level (m)

Condition grade 1 Condition grade 2 Condition grade 3 Condition grade 4 Condition grade 5

The defence fragility curves are probabilistic, reflecting the fact that there is not necessarily a defined water level giving the threshold of defence breach but more a range of water levels within which a defence has a chance of withstanding and a chance of breaching. This range is sandwiched in between the water levels that the defence definitely can and cannot withstand. Given the probabilistic nature of the response of a line of defences, there are many potential ways in which flooding may occur for a given water level. There may be no breach along the entire length of defence, or a breach in one small location, or a breach in several small locations, or a breach along the entire defence. The NaFRA model takes into account the many possible outcomes and combinations of defence

failure, which is a major advantage over other flood models that cannot consider all the possible flooding scenarios. The fragility curves don’t consider the frequency and timing of flood loading against a defence; if high water levels occur in rapid succession and weaken a defence, the only way of accounting for this is to carry out an inspection and update the NFCDD with the deteriorated defence condition grade.

At this stage, the model is taking into account the probability of the event occurring (i.e. the return period associated with the water level) and the probability of defence failure. The flooding conditions associated with each different pattern of defence failure and each coastal water level therefore have a specific probability associated with them.

Assessment of flood hazard

The assessment of flood hazard is carried out by using the Rapid Flood Spreading Method (RFSM) to spread the flood water over the floodplain. The RFSM is a quick approach that calculates the flood water depth and extent in the floodplain by spreading the flood water volume over the land according to the topography. The main advantage of this approach is that it is a computationally efficient method for calculating flood hazard for the many combinations of water level and defence failure patterns that have been outlined in the sections above. A full, technical description of RFSM is given in Lhomme et al. (2009).

The many combinations of water level and defence failure are modelled using a Monte Carlo technique coupled with the RFSM. The Monte Carlo technique samples possible outcomes from the defence fragility curves and generates a set of around 1000 combinations of defence failure patterns for each water level. The statistical properties of the sample given by the Monte Carlo simulation reflect the statistical properties of the fragility curves. The RFSM is used to spread the flood water for each of the 1000 combinations of flood pattern generated from the Monte Carlo simulation. This is then done for every coastal water level (i.e. every return period) that is modelled. The efficiency of the RFSM technique is central to the practical implementation of this approach.

The RFSM is a simplified hydraulic model that takes the inputs of flood volumes from breached or overtopped defences, spreads the water over the floodplain topography and produces the output of flood depths. The approach divides the floodplain into areas called Impact Zones (IZs) which are topographic depressions where water accumulates in the case of flooding. The RFSM spreads the flood volumes by filling the IZs adjacent to the input points and spilling any excess to the neighbouring IZs. The IZs closest to a defence breach or location of overtopping of a defence or natural ground are filled first and then the flood water spills to IZs further inland.

The outputs of the flood hazard assessment are depth - probability relationships for each grid square of the floodplain. The NaFRA model calculations are based on 50 metre grid squares. The results show the probability of flooding to a range of depths.

Assessment of flood risk to habitats

The assessment of flood risk to habitats combines the flood hazard assessment with the exposure and sensitivity of the receptors. The flood risk to habitats is expressed in terms of area of habitat loss.

The exposure of a receptor is assessed by comparing the locations of the flooding with the spatial distribution of habitats. This simply checks whether the habitat is exposed to flooding under each of the scenarios of flood hazard. The sensitivity of the receptor was assessed with expert-derived sensitivity matrices, giving probability of loss for a range of potential combinations of flood duration and flood frequency. The information from the hazard assessment on probability of flooding to a range of depths was translated using simple rules to duration - frequency data. At the level of each 50 m model cell (or grid square), where there is habitat and flood hazard present, the range of duration-frequencies given by the hazard outputs are combined with the corresponding probabilities of habitat loss and aggregated to give a total probability of habitat loss for the grid square. This is then multiplied by the total area of the grid square (it is assumed that where habitat is present within a 50 m grid square, it fills the square) to give an overall figure for area of habitat loss. The results give the average habitat loss over the full range of possible flood scenarios, from high frequency - low consequence events to low frequency - high consequence events.

Appendix J2 Modelling Calculation: Worked Example

Approach

This section aims to provide a more detailed description of the steps involved in the modelling and is also the subject of a Technical Note released as a complimentary project output (HR Wallingford, 2011). The modelling approach used in this study takes into account the best-available expert understanding of habitat sensitivity to two aspects of coastal flooding; flood duration and flood frequency.

The modelling methodology is outlined, and a simplified worked example is presented for Site X, which supports Habitat X shown in Figure 3.2.

Preparing the results of a NaFRA simulation for use in analysis

The main output of the NaFRA analysis is a table of depth-probabilities for each model grid square (the NaFRA model represents the floodplain as a 50 m × 50 m grid). The depth-probability table gives the probability of exceedence for a number of depths between 0 m and 3.25 m (which is the maximum depth exceedence threshold available from the NaFRA results). Two example depth-exceedence maps for Site X are shown in Figures J2.1 and J2.2. Figure J2.1 shows a relatively low probability of flooding of Site X but a slightly higher probability in the south west area of the map. Figure J2.2 shows a uniformly low probability of flooding over 3.25 metres depth.

Creating 50 m rasters of habitat coverage

To estimate the area of habitat within the flooded model grid squares from the NaFRA simulation, the habitat mapping is converted from vector data (shapefiles that delineate the boundary of an area as a smooth line) to raster data (which overlays a grid over the land and identifies which grid squares have habitat present in them, so each area of habitat has hard, squared edges in line with the raster grid) at the 50 m × 50 m resolution of the model results. The raster layers that are produced are an approximation of the vector layer; a comparison of the vector and raster layers for Habitat X at Site X is shown in Figure J2.3. The raster representation does not exactly match the original vector files and in this example there is slightly more habitat area in the vector outline than in the raster boundary, particularly looking at the northern boundary of the habitat. The implications of this are that the overall habitat loss figures may slightly over- or under-estimate the actual loss for each area of habitat. The inaccuracies introduced by this step of the analysis process are, however, very minor compared to the uncertainties in the habitat mapping itself.

Converting depth exceedence to duration

The tables presenting the probability flood depth-exceedence derived from NaFRA are converted into a probability of flood duration for use with the habitat sensitivity matrices. A simple conversion table (Table J2.1) is used to calculate duration from depth based on topography. The calculation assumes that grid squares that are lower than their neighbouring grid squares will drain more slowly, and the higher grid squares will drain quickly. This approach is a bespoke solution developed for this project and it is recognised that this is a simplified representation of the real processes that was adopted for the purposes of this national assessment. The basic depth-duration table is provided in Table J2.1 below.

Table J2.1 Conversion of depth to duration

Duration Depth lower bound Depth upper bound

1 hour 0 0.05

12 hours 0.05 0.35

24 hours 0.35 0.55

48 hours: 2 days 0.45 1

168 hours: 1 week 1 1.75

336 hours: 2 weeks 1.75 2.25

730 hours: 1 month 2.25 3.25

4380 hours: 6 months 3.25 +

The model uses the depth duration conversion table to identify the probability of depth exceedence at both the upper and lower bounds of depth from the NaFRA results for each duration in the conversion table. The lower bound is subtracted from the upper bound to give the probability of experiencing one or more floods of the nominal duration. This simple approach works on the basis that the flood spreading model in NaFRA spills water to ‘impact zones’, which are discrete topographical ‘buckets’ within the floodplain. The route of flood water out of the impact zone when the water level is below the communication level with neighbouring impact zones is through drainage into the soil, which means that the flood depth of each model cell within the impact zone is strongly related to its nearness to the impact zone communication level (which is the maximum water level over the impact zone). The route of flood water out of the impact zone when the water level is above the communication level with neighbouring impact zones is through spilling into the neighbouring impact zones. These characteristics of the model mean that higher ground experiences lower flood depths and thus lower durations, accounting for a faster draining process to lower ground. Lower ground experiences higher flood depths and thus longer durations, accounting for a slower draining process through drainage into the soil.

The outputs from this calculation are tables of flood duration-exceedence probability. Exceedence probability (which gives the chance of flooding for any length of time over a given duration) is converted to probability of

flooding for each specific duration by subtracting the exceedence probability for the following duration in the table (see Table J2.2 for an example).

Table J2.2 Example calculation of duration-probability table for one model grid square

Exceedance Flood Duration Probability Probability 11 0.3 hours 12 0.7 0.2 10.50.2 20.30.1 days 70.20.1 14 0.1 0.05 1 0.05 0.043 months 6 0.007 0.0069 12 0.0001

The results give the probability of flood duration for each model grid square and this can be mapped for each duration in the table. Figures J2.4 and J2.5 are example maps of the probability of a flood of 1 hour in duration and 24 hours duration respectively. Figures J2.4 and J2.5 show that for Site X large areas of Habitat X are not prone to short duration flood events (i.e. 1 hour) but are more prone to longer duration events (24 hours) due to the low lying topography of the area, which drains relatively slowly. The duration was calculated from depth, as explained above. In the figures, the redder areas have a higher probability of exceeding the stated depth. Figure J2.4 shows a low probability of a 1 hour flood over most of the area shown with slightly greater probability along the west of Site X (the middle part of the figure). Figure J2.5 shows a low probability of flooding of 24 hours duration across most of the area, but for a slightly greater probability in the north western area and some along the eastern and northern edge of the site. Compared to the short duration event shown in Figure J2.4, more of the area is prone to this longer term event.

Using flood depth probabilities to estimate loss

The modelling approach assumes that the chance of habitat loss due to flooding depends on the frequency of flooding as well as the duration. The results described above give the probability of at least one flood of a specific duration occurring. To estimate the chance that more than one flood event will occur within a single year, a statistical analysis is used to calculate the probability of each combination in the habitat sensitivity matrix. A flood event of the required depth/duration is assumed to be a Bernoulli random variable and the probability of getting exactly k floods of the required duration in a single year is given by:

n! kKP )( == k − pp )1( −kn (1) − knk )!(!

Where n is the number of highest diurnal tides in a simulated year, k is the number of flood events of the required duration that occur within the year and p is the probability of achieving at least one event. The outputs from this

calculation give the probability of flood hazard for more than one event per year (the ‘Events Per Year’ columns in the habitat sensitivity matrices. The probability of flood hazard for less frequent events (the ‘Years between Events’ columns in the sensitivity matrices) is provided directly by the NaFRA data which considers different return periods.

To estimate the chance of habitat loss across the study area, the probability of every combination of frequency and duration in the habitat sensitivity matrix is calculated using Equation 1. This flood hazard probability is then multiplied by the probability of habitat loss (given by the sensitivity matrix) to give the joint probability of the hazard occurring and habitat loss arising from the hazard.

For each model cell where there is flooding and habitat present, the calculation of the joint probability of the hazard occurring and habitat loss arising for each duration/frequency combination in the sensitivity matrix is carried out. Figures J2.6, J2.7 and J2.8 show the steps described above. First, the probability of each flood duration is calculated (Figure J2.6). Second, the probability of each duration-frequency combination is calculated (Figure J2.7). The NaFRA model predicts depth of flooding, which was converted to duration of flooding and both frequency and duration were used to assess the sensitivity of the habitat to suffering loss or irreversible damage or change due to flooding. Finally, the probability of loss given each duration-frequency combination is calculated (Figure J2.8) using the appropriate habitat sensitivity matrix.

Equation 2 shows the calculation of the joint probability of the hazard occurring and habitat loss arising from the hazard given the flood hazard probability and the probability of habitat loss.

P(Loss) = P(Event ‘X’) x P(Loss | Event ‘X’) (2) where P(Event ‘X’) is defined as a coastal flood of specific duration ‘t’ occurring with frequency 1/‘k’ and P(Loss | Event ‘X’) is defined as the probability of habitat loss given event X (as provided by the sensitivity matrices).

The overall probability of loss of the habitat in the flooding cell can be found by summing the probability of loss for each combination of duration and frequency. The probability of loss is multiplied by the area of habitat (which is equal to the 2500 m2 area of the 50 m × 50 m cell since the vector to raster translation assumes that where habitat is present in a cell, it fills the cell completely). This gives the area of habitat loss. This calculation is done for all model cells to give the total area of habitat loss.

The 50 m grid square model outputs have been aggregated to a 5 km square grid scale for mapping outputs. This aggregation has been undertaken as the representation of variation between neighbouring 50 m grid squares is highly uncertain. Consequently, it would not be appropriate for the mapped outputs to be available at the smaller scale for use in local habitat management. The results tables are based on the 50m resolution model outputs.

Key Coastal Zone Adaptation to Climate Change Vector Representation of Site X P(Flood) = 1.0 Figure J2.1 Probability of Flood Depth Exceeding 0.0m P(Flood) = 0.0

March 2011 0km 1km 24903-S22a.ai lowec

This map is reproduced from the OS map by HR Wallingford with the permission of the Controller of Her Majesty’s Stationary Office, Crown Copyrigh. Unauthorised reproduction infringes Crown Copyright and may lead to prosecution of civil proceedings: Licence Number 100019904 Key Coastal Zone Adaptation to Climate Change Vector Representation of Site X P(Flood) = 1.0 Figure J2.2 Probability of Flood Depth Exceeding 3.25m P(Flood) = 0.0

March 2011 0km 1km 24903-S23a.ai lowec

This map is reproduced from the OS map by HR Wallingford with the permission of the Controller of Her Majesty’s Stationary Office, Crown Copyrigh. Unauthorised reproduction infringes Crown Copyright and may lead to prosecution of civil proceedings: Licence Number 100019904 Key Vector Representation of Site X Raster Representation of Site X

Coastal Zone Adaptation to Climate Change

Figure J2.3 Vector and Raster Representation of Habitat at Site X

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Vector Representation of Site X

Probability of 1 hour flood: P(Flood) = 1.0

P(Flood) = 0.0

0km 1km

Coastal Zone Adaptation to Climate Change

Figure J2.4 Spatial Variation in Probability of 1 Hour Flood, Site X

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Probability of 24 hour flood: P(Flood) = 1.0

P(Flood) = 0.0

0km 1km

Coastal Zone Adaptation to Climate Change

Figure J2.5 Spatial Variation in Probability of 24 Hour Flood, Site X

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Sample Flooding Cell

Probability of Impact Cell 'X' Flooding for Duration 'T' Probability Cell 'X' 0km 1km Coastal Zone Adaptation Duration to Climate Change

Figure J2.6 Annual Probablities That Cell Floods for Different Durations

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Sample Flooding Cell

Probability of Impact Cell 'X' flooding 'K' times for Duration 'T'

Probability of Impact Cell 'X' Flooding for Duration 'Y' Probability

Number of Events Probability Cell 'X' 0km 1km

Duration Coastal Zone Adaptation to Climate Change

Figure J2.7 Probability of Frequency and Duration of Flooding, K Flood Events of Duration T

March 2011 24903-S28a.ai lowec

This map is reproduced from the OS map by HR Wallingford with the permission of the Controller of Her Majesty’s Stationary Office, Crown Copyrigh. Unauthorised reproduction infringes Crown Copyright and may lead to prosecution of civil proceedings: Licence Number 100019904 Key Sensitivity matrix for irreversible damage and loss of habitat X. Vector Representation of Site X

Sample Flooding Cell

Note: The 50m grid square model outputs have been aggregated to a 5km square grid scale for mapping outputs.

Probability of Impact Cell 'X' flooding 'K' times for duration 'T'

0.25

0.2

0.15 bability

Probability0.1o of Impact Cell 'X' flooding for duration 'T' Pr 0.14 0.05 0.12 0 0.1 1357911131517192123Number of Events 0.08 ability 0.06b 0km 1km Pro 0.04 Coastal Zone Adaptation 0.02 to Climate Change 0 Cell 'X' 123456789 Duration Figure J2.8 Probability of K Events of Duration T Resulting in Irreversible Loss of Habitat X

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Appendix K Habitat Extents at Risk of Loss Within Each Type of Designated Area and Outside Designated Areas

Table K.1 Extents of all selected BAP habitats within SAC sites in the coastal floodplain at risk of loss

Total Habitat Current Projected additional risk to all selected BAP habitats in SAC sites resulting from climate change scenarios (Ha) (Ha) in Risk (Ha) Interpretation: The average loss of fens under scenario ‘2100 medium with defences maintained’ would be 23ha (current) + 3ha (additional risk) = 26ha. Habitat coastal floodplain 2010 2030MM 2060LM 2060MM 2060HM 2100LM 2100MM 2100HM 2030MD 2060MD 2100MD

CFPGM Grassland 4,018 169 29 37 37 39 43 46 49 49 66 73

CFPGM Ditches 167 6 3 1 1 1 2 2 2 5 2 3

D. Wood 1,831 46 5 8 12 9 13 9 10 11 19 17

LRB 2,537 46 28 32 32 32 32 32 32 56 72 73

Reed (species) 927 40 13 16 16 17 18 18 18 17 17 18

Fens 1,630 23 1 1 1 1 1 1 1 4 4 4

Lakes 580 18 1 0 0 0 0 0 1 1 1 1

Reed (habitat) 927 14 8 9 9 10 10 10 10 10 9 10

Ponds 192 8 3 2 2 3 3 3 3 4 3 4

PMGRP 1 0 0 0 0 0 0 0 0 0 0 0

SL 306 0 0 0 0 0 0 0 0 0 0 0

Totals 12,190 356 83 99 103 103 112 111 116 147 184 193 Habitat codes: LRB – Lowland raised bog, CFPGM – Coastal and floodplain grazing marsh, SL – Saline lagoons, Reed (habitat) – reedbed habitat only, Reed (species) – reedbed taking faunal species interest into account, PMGRP – Purple moor grass and rush pasture, D. wood – Deciduous wood Scenario references are year, UKCP09 emission scenario (L = low, M = medium, H = high), defence status (M = maintained, D = degraded) Figures represent the average complete loss in area of habitat that could be experienced under each climate change scenario. Habitats ordered by extent of habitat at risk of loss. Total pond extent is presented, not priority ponds. It is estimated that around 20% of ponds nationally will be priority ponds. However, this percentage rises when ponds are located in designated sites.

Table K.2 Extents of all selected BAP habitat within SPA sites in the coastal floodplain at risk of loss

Total Habitat Current Projected additional risk to all selected BAP habitats in SPA sites resulting from climate change scenarios (Ha) (Ha) in Risk (Ha) Interpretation: The average loss of fens under scenario ‘2100 medium with defences maintained’ would be 25ha (current) + 4ha (additional risk) = 29ha. Habitat coastal floodplain 2010 2030MM 2060LM 2060MM 2060HM 2100LM 2100MM 2100HM 2030MD 2060MD 2100MD

CFPGM Grassland 19,900 1090 147 154 157 162 172 183 191 248 303 335

CFPGM Ditches 829 38 3 6 6 6 7 7 8 16 11 13

LRB 1,883 88 0 2 1 2 1 2 2 34 54 55

Reed (species) 2,076 72 7 14 14 15 16 17 17 15 15 18

D. Wood 1,999 54 2 6 12 8 13 11 13 16 21 21

Reed (habitat) 2,076 29 4 8 8 9 9 9 10 8 9 9

Fens 1,729 25 1 1 1 1 1 1 1 4 4 4

Ponds 354 24 0 2 2 3 3 3 4 4 4 5

Lakes 643 19 0 0 R 0 R R 0 0 0 0

PMGRP 1 0 0 0 0 0 0 0 0 0 0 0

SL 893 0 0 0 0 0 0 0 0 0 0 0

Totals 30,308 1410 160 185 194 198 213 225 236 337 413 452 Habitat codes: LRB – Lowland raised bog, CFPGM – Coastal and floodplain grazing marsh, SL – Saline lagoons, Reed (habitat) – reedbed habitat only, Reed (species) – reedbed taking faunal species interest into account, PMGRP – Purple moor grass and rush pasture, D. wood – Deciduous wood Scenario references are year, UKCP09 emission scenario (L = low, M = medium, H = high), defence status (M = maintained, D = degraded) Figures represent the average complete loss in area of habitat that could be experienced under each climate change scenario. Habitats ordered by extent of habitat at risk of loss. Total pond extent is presented, not priority ponds. It is estimated that around 20% of ponds nationally will be priority ponds. However, this percentage rises when ponds are located in designated sites.

Table K.3 Extents of all selected BAP habitat within Ramsar sites in the coastal floodplain at risk of loss

Total Habitat Current Projected additional risk to all selected BAP habitats in Ramsar sites resulting from climate change scenarios (Ha) (Ha) in risk (Ha) Interpretation: The average loss of fens under scenario ‘2100 medium with defences maintained’ would be 25ha (current) + 4ha (additional risk) = 29ha. Habitat coastal floodplain 2010 2030MM 2060LM 2060MM 2060HM 2100LM 2100MM 2100HM 2030MD 2060MD 2100MD

CFPGM Grassland 23,192 942 89 153 156 161 171 182 190 213 303 335

CFPGM Ditches 966 44 3 6 6 6 7 7 8 8 11 13

Reed (species) 2,007 72 9 14 14 15 15 17 17 15 15 17

LRB 300 63 0 0 0 0 0 0 0 14 12 13

D. Wood 1,428 50 6 7 8 9 9 12 13 13 14 17

Reed (habitat) 2,007 28 6 9 9 10 10 10 11 9 9 10

Fens 1,572 25 0 1 1 1 1 1 1 4 4 4

Lakes 621 17 1 1 0 1 0 0 1 0 1 1

Ponds 338 23 1 2 2 3 3 3 3 3 4 5

PMGRP 0 0 0 0 0 0 0 0 0 0 0 0

SL 835 0 0 0 0 0 0 0 0 0 0 0

Totals 31,259 1236 109 183 188 195 206 222 234 270 364 406 Habitat codes: LRB – Lowland raised bog, CFPGM – Coastal and floodplain grazing marsh, SL – Saline lagoons, Reed (habitat) – reedbed habitat only, Reed (species) – reedbed taking faunal species interest into account, PMGRP – Purple moor grass and rush pasture, D. wood – Deciduous wood Scenario references are year, UKCP09 emission scenario (L = low, M = medium, H = high), defence status (M = maintained, D = degraded) Figures represent the average complete loss in area of habitat that could be experienced under each climate change scenario. Habitats ordered by extent of habitat at risk of loss. Total pond extent is presented, not priority ponds. It is estimated that around 20% of ponds nationally will be priority ponds. However, this percentage rises when ponds are located in designated sites.

Table K.4 Extents of all selected BAP habitat outside designated sites in the coastal floodplain at risk of loss

Total Habitat Current Projected additional risk to all selected BAP habitats outside designated sites resulting from climate change scenarios (Ha) (Ha) in Risk (Ha) Interpretation: The average loss of fens under scenario ‘2100 medium with defences maintained’ would be 3ha (current) + 4ha (additional risk) = 7ha. Habitat coastal floodplain 2010 2030MM 2060LM 2060MM 2060HM 2100LM 2100MM 2100HM 2030MD 2060MD 2100MD

CFPGM Grassland 57302 2797 2973 2982 3003 3001 3022 3030 3055 3018 3151 3220

CFPGM Ditches 2388 83 81 88 89 89 90 90 92 90 95 97

D. Wood 2976 97 100 110 111 113 114 121 128 109 115 127

Ponds 1436 33 38 39 40 40 41 40 42 41 42 45

Reed (species) 148 12 15 13 14 15 14 15 16 13 14 15

Lakes 704 12 17 15 15 15 16 16 17 16 16 18

Reed (habitat) 149 5 5 5 5 5 5 6 6 5 5 6

Fens 25 3 3 3 3 3 3 3 3 4 4 4

PMGRP 83 3 3 3 3 3 3 3 3 3 3 4

LRB 24 0 7 6 7 6 7 6 6 8 8 7

SL 153 0 0 0 0 0 0 0 0 0 0 0

Totals 65239 3040 3237 3261 3285 3285 3309 3325 3361 3302 3448 3537 Habitat codes: LRB – Lowland raised bog, CFPGM – Coastal and floodplain grazing marsh, SL – Saline lagoons, Reed (habitat) – reedbed habitat only, Reed (species) – reedbed taking faunal species interest into account, PMGRP – Purple moor grass and rush pasture, D. wood – Deciduous wood Scenario references are year, UKCP09 emission scenario (L = low, M = medium, H = high), defence status (M = maintained, D = degraded) Figures represent the average complete loss in area of habitat that could be experienced under each climate change scenario. Habitats ordered by extent of habitat at risk of loss. Total pond extent is presented, not priority ponds. It is estimated that around 20% of ponds nationally will be priority ponds. However, this percentage rises when ponds are located in designated sites.

Appendix L Habitat Extents at Risk of Loss Within Environment Agency Regions

Table L.1 Extents of all selected BAP habitats within the coastal floodplain at risk of loss within environment agency anglian region

Total Habitat Current Projected additional risk to all selected BAP habitats in EA Anglian Region resulting from climate change scenarios (Ha) (Ha) in Risk (Ha) Interpretation: The average loss of fens under scenario ‘2100 medium with defences maintained’ would be 28ha (current) + 4ha (additional risk) = 32ha. Habitat coastal floodplain 2010 2030MM 2060LM 2060MM 2060HM 2100LM 2100MM 2100HM 2030MD 2060MD 2100MD

CFPGM Grassland 20073 1351 99 121 136 149 160 153 158 207 331 362

CFPGM Ditches 836 50 5 5 6 6 7 7 7 8 12 15

D. Wood 3471 91 5 15 13 20 20 23 19 22 26 27

Reed (species) 918 58 6 11 11 13 12 15 14 8 12 14

Ponds 859 31 3 6 6 7 8 8 8 8 10 12

Fens 1707 28 0 1 0 0 0 0 0 4 4 4

Reed (habitat) 918 27 5 7 7 8 8 10 10 7 8 9

Lakes 938 21 2 2 2 2 3 3 3 3 4 5

PMGRP 73 3 0 0 0 0 0 0 0 0 0 0

LRB 47 1 0 0 0 0 0 0 0 0 1 0

SL 332 0 0 0 0 0 0 0 0 0 0 0

Totals 29255 1634 120 161 174 197 210 209 209 260 400 439 Habitat codes: LRB – Lowland raised bog, CFPGM – Coastal and floodplain grazing marsh, SL – Saline lagoons, Reed (habitat) – reedbed habitat only, Reed (species) – reedbed taking faunal species interest into account, PMGRP – Purple moor grass and rush pasture, D. wood – Deciduous wood Scenario references are year, UKCP09 emission scenario (L = low, M = medium, H = high), defence status (M = maintained, D = degraded) Figures represent the average complete loss in area of habitat that could be experienced under each climate change scenario. Habitats ordered by extent of habitat at risk of loss. Total pond extent is presented, not priority ponds. It is estimated that around 20% of ponds nationally will be priority ponds. However, this percentage rises when ponds are located in designated sites.

Table L.2 Extents of all selected BAP habitat within the coastal floodplain at risk of loss within environment agency midlands region

Total Habitat Current Projected additional risk to all selected BAP habitats in EA Midlands Region resulting from climate change scenarios (Ha) (Ha) in Risk (Ha) Interpretation: The average loss of fens under scenario ‘2100 medium with defences maintained’ would be 0ha (current) + 0ha (additional risk) = 0ha Habitat coastal floodplain 2010 2030MM 2060LM 2060MM 2060HM 2100LM 2100MM 2100HM 2030MD 2060MD 2100MD

CFPGM Grassland 231 1 0 0 0 0 0 0 0 1 0 0

CFPGM Ditches 10 0 0 0 0 0 0 0 0 0 0 0

D. Wood 253 0 1 1 1 1 1 1 1 1 1 1

Fens 1 0 0 0 0 0 0 0 0 0 0 0

SL 0 0 0 0 0 0 0 0 0 0 0 0

Lakes 45 0 0 0 0 0 0 0 0 0 0 0

PMGRP 0 0 0 0 0 0 0 0 0 0 0 0

Ponds 71 0 0 0 0 0 0 0 0 0 0 0

Reed (habitat) 6 0 0 0 0 0 0 0 0 0 0 0

Reed (species) 6 0 0 0 0 0 0 0 0 0 0 0

LRB 0 0 0 0 0 0 0 0 0 0 0 0

Totals 616 1 1 1 1 1 1 1 1 2 1 1 Habitat codes: LRB – Lowland raised bog, CFPGM – Coastal and floodplain grazing marsh, SL – Saline lagoons, Reed (habitat) – reedbed habitat only, Reed (species) – reedbed taking faunal species interest into account, PMGRP – Purple moor grass and rush pasture, D. wood – Deciduous wood Scenario references are year, UKCP09 emission scenario (L = low, M = medium, H = high), defence status (M = maintained, D = degraded) Figures represent the average complete loss in area of habitat that could be experienced under each climate change scenario. Habitats ordered by extent of habitat at risk of loss. Total pond extent is presented, not priority ponds. It is estimated that around 20% of ponds nationally will be priority ponds. However, this percentage rises when ponds are located in designated sites.

Table L.3 Extents of all selected BAP habitats within the coastal floodplain at risk of loss within environment agency north east region

Total Habitat Current Projected additional risk to all selected BAP habitats in EA North East Region resulting from climate change scenarios (Ha) (Ha) in Risk (Ha) Interpretation: The average loss of fens under scenario ‘2100 medium with defences maintained’ would be 1ha (current) + 1ha (additional risk) = 2ha Habitat coastal floodplain 2010 2030MM 2060LM 2060MM 2060HM 2100LM 2100MM 2100HM 2030MD 2060MD 2100MD

CFPGM Grassland 2359 64 6 8 1 2 8 1 4 3 15 13

CFPGM Ditches 98 2 1 1 0 1 1 1 1 1 1 1

LRB 2301 41 25 41 32 32 41 32 32 56 72 64

D. Wood 697 21 R 2 R 0 3 3 2 2 6 4

Reed (species) 344 6 0 0 0 0 1 0 1 1 0 1

Ponds 246 4 0 1 0 0 1 0 1 1 1 1

Fens 69 1 0 0 0 0 0 0 0 0 0 0

Lakes 182 1 1 1 1 1 1 1 1 1 1 1

Reed (habitat) 344 1 1 1 1 1 1 1 1 1 1 1

PMGRP 7 0 0 0 0 0 0 0 0 0 0 0

SL 161 0 0 0 0 0 0 0 0 0 0 0

Totals 6465 140 32 54 32 36 56 38 42 65 96 85 Habitat codes: LRB – Lowland raised bog, CFPGM – Coastal and floodplain grazing marsh, SL – Saline lagoons, Reed (habitat) – reedbed habitat only, Reed (species) – reedbed taking faunal species interest into account, PMGRP – Purple moor grass and rush pasture, D. wood – Deciduous wood Scenario references are year, UKCP09 emission scenario (L = low, M = medium, H = high), defence status (M = maintained, D = degraded) Figures represent the average complete loss in area of habitat that could be experienced under each climate change scenario. Habitats ordered by extent of habitat at risk of loss. Total pond extent is presented, not priority ponds. It is estimated that around 20% of ponds nationally will be priority ponds. However, this percentage rises when ponds are located in designated sites.

Table L.4 Extents of all selected BAP habitat within the coastal floodplain at risk of loss within environment agency north west region

Total Habitat Current Projected additional risk to all selected BAP habitats in EA North West Region resulting from climate change scenarios (Ha) (Ha) in Risk (Ha) Interpretation: The average loss of fens under scenario ‘2100 medium with defences maintained’ would be 0ha (current) + 1ha (additional risk) = 1ha Habitat coastal floodplain 2010 2030MM 2060LM 2060MM 2060HM 2100LM 2100MM 2100HM 2030MD 2060MD 2100MD

CFPGM Grassland 11590 426 24 7 34 14 25 16 69 R R 48

CFPGM Ditches 483 14 R 0 0 0 0 0 2 R R 1

LRB 245 9 R R 0 0 R 0 0 1 0 1

D. Wood 126 5 R 0 0 0 0 0 0 0 R 0

Ponds 93 3 0 0 0 0 0 0 0 0 0 0

Lakes 46 1 0 0 0 0 0 0 0 0 0 0

Reed (species) 121 1 0 0 0 0 0 0 0 0 0 0

Fens 46 0 0 0 0 0 0 0 0 0 0 0

SL 100 0 0 0 0 0 0 0 0 0 0 0

PMGRP 1 0 0 0 0 0 0 0 0 0 0 0

Reed (habitat) 121 0 0 0 0 0 0 0 0 0 0 0

Totals 12814 459 21 6 34 14 24 16 71 R R 50 Habitat codes: LRB – Lowland raised bog, CFPGM – Coastal and floodplain grazing marsh, SL – Saline lagoons, Reed (habitat) – reedbed habitat only, Reed (species) – reedbed taking faunal species interest into account, PMGRP – Purple moor grass and rush pasture, D. wood – Deciduous wood Scenario references are year, UKCP09 emission scenario (L = low, M = medium, H = high), defence status (M = maintained, D = degraded) Figures represent the average complete loss in area of habitat that could be experienced under each climate change scenario. Habitats ordered by extent of habitat at risk of loss. Total pond extent is presented, not priority ponds. It is estimated that around 20% of ponds nationally will be priority ponds. However, this percentage rises when ponds are located in designated sites.

Table L.5 Extents of all selected BAP habitats within the coastal floodplain at risk of loss within environment agency southern region

Total Habitat Current Projected additional risk to all selected BAP habitats in EA Southern Region resulting from climate change scenarios (Ha) (Ha) in Risk (Ha) Interpretation: The average loss of fens under scenario ‘2100 medium with defences maintained’ would be 1ha (current) + 3ha (additional risk) = 4ha Habitat coastal floodplain 2010 2030MM 2060LM 2060MM 2060HM 2100LM 2100MM 2100HM 2030MD 2060MD 2100MD

LRB 0 0 0 0 0 0 0 0 0 0 0 0

CFPGM Grassland 21297 564 48 44 55 49 47 51 70 58 71 89

CFPGM Ditches 887 19 R 1 1 1 1 2 2 3 2 3

D. Wood 569 51 2 3 14 7 8 9 26 7 5 18

Reed (species) 461 33 3 5 6 6 6 6 8 9 6 8

Ponds 314 12 1 2 3 2 2 2 4 3 2 4

Lakes 254 10 0 -1 0 0 0 0 0 0 R 0

Reed (habitat) 461 10 0 1 1 2 1 2 2 2 1 2

Fens 47 1 0 0 0 0 0 0 0 0 0 0

SL 505 0 0 0 0 0 0 0 0 0 0 0

PMGRP 0 0 0 0 0 0 0 0 0 0 0 0

Totals 24336 690 53 54 79 65 64 70 110 80 85 122 Habitat codes: LRB – Lowland raised bog, CFPGM – Coastal and floodplain grazing marsh, SL – Saline lagoons, Reed (habitat) – reedbed habitat only, Reed (species) – reedbed taking faunal species interest into account, PMGRP – Purple moor grass and rush pasture, D. wood – Deciduous wood Scenario references are year, UKCP09 emission scenario (L = low, M = medium, H = high), defence status (M = maintained, D = degraded) Figures represent the average complete loss in area of habitat that could be experienced under each climate change scenario. Habitats ordered by extent of habitat at risk of loss. Total pond extent is presented, not priority ponds. It is estimated that around 20% of ponds nationally will be priority ponds. However, this percentage rises when ponds are located in designated sites.

Table L.6 Extents of all selected BAP habitat within the coastal floodplain at risk of loss within environment agency south west region

Total Habitat Current Projected additional risk to all selected BAP habitats in EA South West Region resulting from climate change scenarios (Ha) (Ha) in Risk (Ha) Interpretation: The average loss of fens under scenario ‘2100 medium with defences maintained’ would be 0ha (current) + 0ha (additional risk) = 0ha Habitat coastal floodplain 2010 2030MM 2060LM 2060MM 2060HM 2100LM 2100MM 2100HM 2030MD 2060MD 2100MD

CFPGM Grassland 31615 1502 164 209 199 224 221 249 205 273 318 324

CFPGM Ditches 1317 41 0 7 7 8 8 9 8 9 12 12

LRB 304 56 0 1 8 8 0 8 8 22 21 30

D. Wood 562 22 1 3 3 2 4 5 5 7 7 8

Ponds 231 9 0 1 1 1 1 1 1 3 2 2

Reed (species) 695 4 1 1 1 2 1 2 1 3 2 2

Reed (habitat) 695 1 0 0 0 0 0 0 0 0 0 0

Lakes 45 1 0 0 0 0 0 0 0 0 0 0

Fens 128 0 0 0 0 0 0 0 0 0 0 0

SL 14 0 0 0 0 0 0 0 0 0 0 0

PMGRP 3 0 0 0 0 0 0 0 0 0 0 0

Totals 34915 1635 166 222 219 245 235 274 228 317 362 378 Habitat codes: LRB – Lowland raised bog, CFPGM – Coastal and floodplain grazing marsh, SL – Saline lagoons, Reed (habitat) – reedbed habitat only, Reed (species) – reedbed taking faunal species interest into account, PMGRP – Purple moor grass and rush pasture, D. wood – Deciduous wood Scenario references are year, UKCP09 emission scenario (L = low, M = medium, H = high), defence status (M = maintained, D = degraded) Figures represent the average complete loss in area of habitat that could be experienced under each climate change scenario. Habitats ordered by extent of habitat at risk of loss. Total pond extent is presented, not priority ponds. It is estimated that around 20% of ponds nationally will be priority ponds. However, this percentage rises when ponds are located in designated sites.

Table L.7 Extents of all selected BAP habitats within the coastal floodplain at risk of loss within environment agency thames region

Total Habitat Current Projected additional risk to all selected BAP habitats in EA Thames Region resulting from climate change scenarios (Ha) (Ha) in Risk (Ha) Interpretation: The average loss of fens under scenario ‘2100 medium with defences maintained’ would be 0ha (current) + 0ha (additional risk) = 0ha Habitat coastal floodplain 2010 2030MM 2060LM 2060MM 2060HM 2100LM 2100MM 2100HM 2030MD 2060MD 2100MD

CFPGM Grassland 415 6 1 1 1 1 1 1 1 1 1 1

CFPGM Ditches 17 0 0 0 0 0 0 0 0 0 0 0

Reed (species) 20 1 R 0 0 0 0 0 0 0 0 0

Fens 1 0 0 0 0 0 0 0 0 0 0 0

LRB 0 0 0 0 0 0 0 0 0 0 0 0

SL 0 0 0 0 0 0 0 0 0 0 0 0

Lakes 0 0 0 0 0 0 0 0 0 0 0 0

PMGRP 0 0 0 0 0 0 0 0 0 0 0 0

Ponds 56 0 0 0 0 0 0 0 0 0 0 0

Reed (habitat) 20 0 0 0 0 0 0 0 0 0 0 0

D. Wood 90 0 0 0 0 0 0 0 0 0 0 0

Totals 600 7 1 1 1 1 1 1 1 1 1 1 Habitat codes: LRB – Lowland raised bog, CFPGM – Coastal and floodplain grazing marsh, SL – Saline lagoons, Reed (habitat) – reedbed habitat only, Reed (species) – reedbed taking faunal species interest into account, PMGRP – Purple moor grass and rush pasture, D. wood – Deciduous wood Scenario references are year, UKCP09 emission scenario (L = low, M = medium, H = high), defence status (M = maintained, D = degraded) Figures represent the average complete loss in area of habitat that could be experienced under each climate change scenario. Habitats ordered by extent of habitat at risk of loss. Total pond extent is presented, not priority ponds. It is estimated that around 20% of ponds nationally will be priority ponds. However, this percentage rises when ponds are located in designated sites.

Appendix M Coastal and Floodplain Grazing Marsh BAP Targets (from BARS)

Maintain the extent of the existing resource of C&FPGM habitat with no net loss. (In particular, ensure that grazing marsh of similar quality is created to landward of flood defences that have been abandoned or breached as sea level rises, by mapping where compensatory habitat will be created in Shoreline Management Plans and other plans set out by statutory agencies).

Target type Maintaining extent Units Hectares

Target values (2005 values represent the baselines)

Country 2005 2010 2015 2020 2030

UK 216140 216140

E 170000 170000

NI 4782 4782

S 1500 1500

W 39858 39858

Additional For habitat to qualify as C&FPGM BAP habitat, it must meet the definition criteria as set information out in the HAP. (See attached revised HAP definition for full details).

Maintain the condition of C&FPGM habitat where already favourable and establish by 2010, management to secure favourable condition for all areas of grazing marsh currently judged as unfavourable. The target condition for all such areas should be favourable or unfavourable recovering by 2020.

Target type Achieving condition Units Hectares

Target values (2005 values represent the baselines)

Country 2005 2010 2015 2020 2030

UK 54036 97263 194526

E 42500 76500 153000

NI 1196 2152 4304

S 375 675 1350

W 9965 17936 35872

Additional Rehabilitation will differ from restoration in that the habitat will conform to the revised information habitat definition and the degree of work to be undertaken will be minimal in comparison. In addition, only parts of the site will be in poor condition. Example of habitat in poor condition that qualifies as BAP habitat. Hydrological regime in place but site inappropriately managed i.e. water levels too low, insufficient or no wet surface features or flooding, inappropriate sward condition, incorrect hedge height, excessive scrub cover. The condition of grazing marsh can be assessed using the list of criteria for higher level agri- environment schemes.

Restore and improve 25,000 ha of relict habitat that does not qualify as C&FPGM habitat by 2020. (e.g. dry C&FPGM with inappropriate hydrological regime, agriculturally improved sites etc by implementing appropriate management at all sites).

Target type Restoration Units Hectares

Target values (2005 values represent the baselines)

Country 2005 2010 2015 2020 2030

UK 6150 12300 24600

E 3750 7500 15000

NI 25 50 100

S 125 250 500

W 2250 4500 9000

Additional Restoration will differ from rehabilitation in that the habitat will not conform to the revised information habitat definition and the degree of restoration work to be undertaken will be significant in comparison. In addition, the whole of the site will be degraded. Example of relict habitat that does not presently qualify as BAP habitat: Hydrological regime no longer in place but typical physical features of C&FPGM present e.g. ditches reflecting land that has previously and more recently been managed as wet grassland and also reflected in either the existing land use and / or botanical communities present e.g. intensively cultivated drained land. Appropriate management will include, (in the first instance), a sustainable and appropriate hydrological regime capable of supporting typical C&FPGM botanical communities (e.g. MG4, MG9, MG11, MG13). Thereafter, an appropriate habitat management regime that ensures continuation of botanical interest with habitat capable of supporting a diverse range of species such as invertebrates, mammals and breeding waders.

T4 Edit target information >

Re-establish 3,200 ha of C&FPGM of wildlife value from appropriate land sources (e.g. arable land) by 2020 (which is capable of supporting a diverse range of invertebrates, mammals and breeding waders).

Target type Expansion Units Hectares

Target values (2005 values represent the baselines)

Country 2005 2010 2015 2020 2030

UK 800 1600 3200

E 625 1250 2500

NI 25 50 100

S 125 250 500

W 25 50 100

Additional Action 1: By 2007 and using tools such as ‘visioning’, identify areas for the future creation information of C&FPGM for potential inclusion in Regional Spatial Strategies and Catchment Flood Management Plans (for England). Priority: re-established area to be adjacent to existing grazing marsh or other semi-natural habitat by 2010. Example of new C&FPGM habitat. Generally agricultural land with no typical physical features of C&FPGM present reflecting land that has not recently been managed as wet grassland and also reflected in either the existing land use and / or botanical communities present e.g. intensively cultivated drained land. In addition, also ensure that grazing marsh of similar quality is created to landward of flood defences that have been abandoned or breached as sea level rises, by mapping where compensatory habitat will be created in Shoreline Management Plans and other plans set out by statutory agencies.