European Site Conservation Objectives: Supplementary advice on conserving and restoring site features Mendip Woodlands Special Area of Conservation (SAC) Site Code: UK0030048 Ebbor Gorge – Chris Westcott Natural England Date of Publication: 22 March 2019 Page 1 of 15 About this document This document provides Natural England’s supplementary advice about the European Site Conservation Objectives relating to Mendip Woodlands SAC. This advice should therefore be read together with the SAC Conservation Objectives available here. This advice replaces a draft version dated January 2019 following the receipt of comments from the site’s stakeholders. You should use the Conservation Objectives, this Supplementary Advice and any case-specific advice given by Natural England when developing, proposing or assessing an activity, plan or project that may affect this site’ This Supplementary Advice to the Conservation Objectives presents attributes which are ecological characteristics of the designated species and habitats within a site. The listed attributes are considered to be those that best describe the site’s ecological integrity and which, if safeguarded, will enable achievement of the Conservation Objectives. Each attribute has a target which is either quantified or qualitative depending on the available evidence. The target identifies as far as possible the desired state to be achieved for the attribute. The tables provided below bring together the findings of the best available scientific evidence relating to the site’s qualifying features, which may be updated or supplemented in further publications from Natural England and other sources. The local evidence used in preparing this supplementary advice has been cited. The references to the national evidence used are available on request. Where evidence and references have not been indicated, Natural England has applied ecological knowledge and expert judgement. You may decide to use other additional sources of information. In many cases, the attribute targets shown in the tables indicate whether the current objective is to ‘maintain’ or ‘restore’ the attribute. This is based on the best available information, including that gathered during monitoring of the feature’s current condition. As new information on feature condition becomes available, this will be added so that the advice remains up to date. The targets given for each attribute do not represent thresholds to assess the significance of any given impact in Habitats Regulations Assessments. You will need to assess this on a case-by-case basis using the most current information available. Some, but not all, of these attributes can also be used for regular monitoring of the actual condition of the designated features. The attributes selected for monitoring the features, and the standards used to assess their condition, are listed in separate monitoring documents, which will be available from Natural England. These tables do not give advice about SSSI features or other legally protected species which may also be present within the European Site. If you have any comments or queries about this Supplementary Advice document please contact your local Natural England adviser or email [email protected] Page 2 of 15 About this site European Site information Name of European Site Mendip Woodlands Special Area of Conservation (SAC) Location Somerset Site Map The designated boundary of this site can be viewed here on the MAGIC website Designation Date 1 April 2005 Qualifying Features See section below Designation Area 253.86ha Designation Changes n/a Feature Condition Status Details of the feature condition assessments made at this site can be found using Natural England’s Designated Sites System Names of component Asham Wood SSSI, Cheddar Wood SSSI, Ebbor Gorge SSSI, Sites of Special Scientific Rodney Stoke SSSI Interest (SSSIs) Relationship with other The boundary of this SAC coincides with North Somerset and Mendip European or International Bats SAC Site designations Site background and geography The Mendip Woodlands SAC comprises four individual woods in Somerset, all located on the southern slope of the Mendip Hills National Character Area (NCA Profile 141). Three of the woods, Cheddar Wood, Ebbor Gorge and Rodney Stoke lie in the west of Mendip while Asham Wood lies in the east. Asham Wood and Ebbor Gorge are both associated with limestone gorges while Cheddar Wood and Rodney Stoke lie on the steep southern slope of the hills. Only one of the woods, Asham, has permanent streams running through it. All four woods are dominated by ash Fraxinus excelsior while both Cheddar Wood and Rodney Stoke have a high population of small-leafed lime Tilia cordata. Notable species present include Purple gromwell Lithospermum purpurocaeruleum, Lily of the valley Convallaria majalis and Wild daffodil Narcissus pseudonarcissus. All the woodlands were managed by coppicing and many were gradually reverting to high forest however some, like Cheddar Wood, are now being put back into coppice with standards. Page 3 of 15 About the qualifying features of the SAC The following section gives you additional, site-specific information about this SAC’s qualifying features. These are the natural habitats and/or species for which this SAC has been designated. Qualifying habitats: • H9180 Tilio-Acerion forests of slopes, screes and ravines * Priority feature Mendip Woodlands in south-west England is a relatively extensive example of Tilio-Acerion forests on limestone. It is a cluster of three ash-dominated woods on Carboniferous limestone comprising W7 (Wet lowland alder wood), W8 (Lowland ash-maple wood) and W10 (Lowland oak wood) NVC types. A rich variety of other trees and shrubs are present, including elm Ulmus spp. and, locally, small-leaved lime Tilia cordata. At Ebbor Gorge elm rather than lime is mixed with ash Fraxinus excelsior in a steep-sided gorge; at both Rodney Stoke and Cheddar Wood lime and ash are found on rocky slopes with patches of deeper soil between the outcrops. Ferns characteristic of this woodland type, such as hart’s-tongue Phyllitis scolopendrium and shield-ferns Polystichum spp., are common. The site is in the centre of the range of common dormouse Muscardinus avellanarius and holds a large population of this species. Qualifying Species: Not Applicable Page 4 of 15 Table 1: Supplementary Advice for Qualifying Features: H9180. Tilio-Acerion forests of slopes, screes and ravines; Mixed woodland on base-rich soils associated with rocky slopes * Attributes Targets Supporting and Explanatory Notes Sources of site-based evidence (where available) Extent and Extent of the Maintain OR if necessary restore There should be no measurable reduction (excluding any trivial Natural England (Various) distribution feature within the total extent of the feature to loss) in the extent and area of this feature, and in some cases, Definitions of Favourable of the feature the site at least 82.98ha, whilst avoiding the full extent of the feature may need to be restored. The Condition for component SSSIs deterioration from its current baseline-value of extent given has been generated using data of Mendip Woodlands SAC extent gathered from the listed site-based surveys. Area (Available from Natural England measurements given may be approximate depending on the on request) JNCC standard data form methods, age and accuracy of data collection, and as a result 82.98ha this value may be updated in future to reflect more accurate information. JNCC data sheet Information from Natural http://jncc.defra.gov.uk/Protected England’s Definitions of The extent of an Annex I habitat feature covers the sum extent Sites/SACselection/sac.asp?EUC Favourable Condition for of all of the component vegetation communities present and ode=UK0030048 component SSSIs. may include transitions and mosaics with other closely- associated habitat features. Where a feature is susceptible to This attribute will be periodically Proportion of wood considered to natural dynamic processes, there may be acceptable variations monitored as part of Natural comprise Tilio-Acerion feature: in its extent through natural fluctuations. Where a reduction in England’s SSSI condition the extent of a feature is considered necessary to meet the assessments. Cheddar Wood – 100% Conservation Objective for another Annex I feature, Natural Ebbor Wood – 50% England will advise on this on a case-by-case basis. Rodney Wood – 60% Asham Wood – 25% For this feature tree roots (particularly of veteran trees) can extend a considerable distance beyond the boundary of the site Asham Wood SSSI = 134ha - they can be impacted by soil compaction (such as caused by (W7, 8, 10) x 25% = 33.5ha vehicles or construction works); agricultural operations or other soil disturbance (like trenches); and agro chemicals or other Cheddar Wood SSSI = 65ha chemicals which get into the soil. (W8) Any loss of woodland area - whether at the edge or in the Ebbor Gorge SSSI = 59ha (W8) middle of a site will reduce the core woodland area where x 50% = 29.5ha woodland conditions are found - these support significant assemblages of species dependent on woodland conditions Rodney Stoke SSSI = 38.4ha (e.g. lichens and bryophytes - being one example). Loss of any (W8) x 60% = 23.04ha woodland area which fragments a site into different parts will clearly disturb the movement of species between the remaining Total = 151.04ha parts of the woodland. In the absence of specific site surveys tailored to identifying Attributes Targets Supporting and Explanatory Notes Sources of site-based evidence (where available) extents of Tilio-Acerion habitat, NVC community W8 has been used as a proxy to the Annex I habitat. This, in part, explains the discrepancy between the JNCC standard data form and the individual Definition of Favourable Condition figures. Further survey effort is needed to determine the proper extent of the Annex 1 habitat (and/or its proxy community W8 as no NVC maps are known to exist) since there are specific areas known to exhibit features such as slopes, screes and ravines, but these are as yet unmapped and undefined.