Ardaun Local Area Plan Habitat Assessment

GALWAY CITY COUNCIL ARDAUN LOCAL AREA PLAN HABITAT ASSESSMENT August 2012 Ardaun LAP Habitat Assessment 2012 Contents 1. Introduction ...................................................................................................................... 3 2. Methodology ..................................................................................................................... 4 3. Results ............................................................................................................................... 4 4. Habitat evaluation .......................................................................................................... 10 5. Recommendations .......................................................................................................... 11 References ............................................................................................................................... 13 Appendix 1: Relevé data .......................................................................................................... 15 Appendix 2: Site Evaluation Criteria of the National Roads Authority (2009) ........................ 17 Appendix 3: Previously recommended habitat management ................................................ 19 - 2 - Ardaun LAP Habitat Assessment 2012 1. Introduction Natura Environmental Consultants were commissioned by Galway City Council to review and assess the habitats within the Ardaun, LAP Phase 1 lands (see Figure 1). This habitat assessment follows on from a previous Habitat Survey Report, prepared by Natura for the wider Ardaun Area in October 2009, which identified a number of habitats and species of high ecological value. This, in turn, was based on the findings of a Habitat Inventory prepared for the entire area of Galway City in 2005 (Natura Environmental Consultants 2005). The brief for this project was as follows: 1. To undertake a more detailed survey and examination of the habitats of high ecological value within the Phase 1 lands, to determine their value having regard to quality, location and scale/fragmentation. 2. To identify other areas/habitats of ecological value and to grade these in terms of quality. This will enable the City Council to attach priorities to these areas. 3. To make recommendations for policies/objectives to avoid and mitigate potential negative impacts on habitats of high ecological value. This should also include advice on the management and land use of such areas within a future urban context and the treatment of boundaries of such sites by adjoining land uses and development. This should take into account the protection and encouragement of biodiversity and the development of green networks and eco-districts. This should also enable the Council to address ecological impacts in the SEA process. Figure 1. Location of the Ardaun LAP in Galway City - 3 - Ardaun LAP Habitat Assessment 2012 2. Methodology 2.1 Field Survey The survey was undertaken by Katharine Duff, Senior Botanist. The site was walked on June 20th and 27th 2012 and changes to habitats recorded in 2009 were noted. Habitats were surveyed following guidelines outlined by Smith et al. (2011) and classified according to Fossitt (2000). A more detailed assessment was undertaken of the habitats in Table 1, which potentially correspond with those listed under Annex I of the EU Habitats Directive (92/43/EEC). This included recording all plant species within three 2m x 2m sample areas (relevés). Relevé data is given in Appendix 1. The extent of each habitat was mapped on OS maps. A dedicated survey of the legally protected small white orchid (Pseudorchis albida) was also carried out within this site. Consultation with Dr Cilian Roden on the status of the small white orchid helped to locate this species. Table 1. Habitat types (after Fossitt 2000) and their corresponding links with Annex I habitats under the EU Habitats Directive Habitat (Fossitt 2000) Annex I EU Habitats Directive Dry calcareous and neutral Semi-natural dry grasslands and scrubland facies on calcareous grassland (GS1) substrates (Festuco-Brometea) (*Important orchid sites) (6210) Exposed calcareous rock (ER2) *Limestone pavements (8240) 2.2 Habitat evaluation Habitats recorded in this survey were evaluated using the system developed for the National Roads Authority (2009) (Appendix 2). This takes into account a number of objective criteria and has been widely applied in the planning of the national roads network. 3. Results 3.1 Habitat survey The habitats recorded on the LAP lands in June 2012 are shown in Figure 2. There have been some changes to the habitats within the Ardaun LAP lands since 2009. An area, located at the eastern edge of the lands, which was identified in 2009 as being mixed scrub (WS1) and unimproved species- rich neutral/calcareous grassland (GS1), has been ‘improved’. The scrub has been removed and the grassland reseeded with agricultural grass species including perennial rye grass (Lolium perenne), meadow grass (Poa pratensis) and Yorkshire fog (Holcus lanatus). The agricultural improvement has reduced the ecological value of the habitat. At the western edge of the LAP lands, an area of spoil and bare ground close to the M6/N6 junction has revegetated to Dry Calcareous and neutral grassland (GS1) The habitats of higher ecological value within the study area are described below: Dry Calcareous and neutral grassland (GS1) Species-rich calcareous grassland occurs at two main locations within the LAP lands: a) At the western side adjacent to the limestone pavement; b) Within 2 large fields at the centre of the site; c) At the north-western side of the site in a number of smaller fields. - 4 - Ardaun LAP Habitat Assessment 2012 Figure 2. Habitat map of the Ardaun LAP lands in June 2012 At the western side, the calcareous grassland forms a mosaic with Dry calcareous heath (HH2) and scrub (WS1) over a shallow heathy substrate. It has a very high species diversity of plants that are indicators of both calcareous, and acidic conditions as well as a degree of dampness. The underlying geology includes limestone, but also some small granite boulders which are a feature of its glacial past and would add to the acidic nature of the substrate. This is also the habitat of the rare and legally protected small white orchid (Pseudorchis albida), of which six plants were found during the survey. A survey of the small white orchid is reported in section 3.2. This habitat conforms to the priority Annex I habitat *Important Orchid Site (6210) as described in the Interpretation Manual of the EU Habitats (2007). This habitat is of high ecological value. Recently there has been scrub clearance ongoing throughout this habitat. The digger machine that is used for the scrub clearance is also disturbing/damaging the grassland in places. - 5 - Ardaun LAP Habitat Assessment 2012 At the centre of the LAP lands the calcareous grassland is also species-rich but not so heathy. There are localised areas of high species diversity with large numbers of heath spotted orchids (Dactylorhiza maculata). This habitat conforms to the Annex I habitat Semi-natural dry grasslands and scrubland facies on calcareous substrates (Festuco-Brometea) (6210). The grassland has not been recently grazed and scrub is encroaching, including burnet rose (Rosa pimpenelifolia) and blackthorn (Prunus spinosa) as well as some bracken (Pteridium aquilinum). Exposed calcareous rock (ER2) This is an area of exposed limestone that conforms to the priority Annex I habitat * Limestone Pavements (8420). It is located at the western side of the site (grid ref. M 3467 2656). It is bounded by the N6 to the west and the new M6 to the north. The limestone pavement includes fragmented areas of exposed weathered limestone bedrock with fissures along natural joints as well as areas of shattered limestone. The extent of limestone pavement has basically not changed, however the habitat is becoming more overgrown with hazel (Corylus avellana) scrub which is growing in the cracks in the limestone or on pockets of species-rich grassland in between the limestone pavement. The area of juniper (Juniperus communis) scrub on the limestone appears to be reduced. There has been some dumping of rubble near the fence along the N6 road. Wet grassland (GS4) Some wet grassland areas were identified in the 2009 survey as potential Turlough habitat (FL6). On reassessing this area in 2012, there are small fragments of wet grassland vegetation covering an area of 5m2 which indicate some localised waterlogging of the substrate. The main species include creeping bent (Agrostis stolonifera), jointed rush (Juncus articulatus/acutiflorus), carnation sedge (Carex panacea) and localised patches of creeping willow (Salix repens). The moss Calliergonella cuspidate, which is indicative of wet and basic conditions was extensive in 2009, is not now present. The wet habitat is very limited and this is likely to be due to a retention of surface water rather than a fluctuation in ground water levels. The ground has also been compacted by a digger machine driving through it. The habitat does not conform to the priority Annex I habitat *Turlough (3180). 3.2 Survey of the small white orchid The small white orchid (Pseudorchis alba) is a legally protected plant (under the Flora Protection Order 1999). A dedicated survey for the species on the Ardaun LAP lands was carried out on 19/20th June, 2012 by Katharine Duff. There were previous plant records from this area by Dr. Cilian Roden (2005). Six plants of

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