Irish Semi Irish Semi-Natural Natural Grasslands Survey
Total Page:16
File Type:pdf, Size:1020Kb
Irish SemiIrish Semi--naturalnatural Grasslands Survey Annual Report No. 2: Counties Cavan, Leitrim, Longford & Monaghan F.H. O’Neill, J.R. Martin, P.M. Perrin, A. Delaney, K.E. McNutt & F.M. Devaney December 2009 BOTANICAL, ENVIRONMENTAL & CONSERVATION CONSULTANTS LTD. www.botanicalenvironmental.com 26 Upper Fitzwilliam Street, Dublin 2 Tel: 01 6619713 Email: [email protected] _______________________________________________________ Acknowledgements We are grateful to everyone who contributed to the planning and completion of this project. The work has been funded by the National Parks and Wildlife Service (Department of the Environment, Heritage and Local Government). We would like to thank Marie Dromey for her guidance throughout the project. Thanks also to Naomi Kingston and Deirdre Lynn for helpful comments on a draft of this report. We acknowledge the help of NPWS field staff and local authority personnel who suggested sites for survey. We also thank staff at the National Biodiversity Data Centre. The assistance of Nick Hodgetts and David Holyoak for identification of some problematic bryophyte samples is also gratefully acknowledged. We are grateful to Simon Barron, Edwina Cole, Niamh Cullen, Orla Daly, Thérèse Higgins, Nigel Mills, Pat Moran, Mieke Muyllaert, Clíodhna Ní Bhroin, Michelle O’Neill, Emma Reeves and Sam Thomas for their hard work in the field. Finally, we thank the farmers and landowners of Cavan, Leitrim, Longford and Monaghan for giving us permission to survey their land and for the background information they provided. Cover: Wet grassland at Moneensauran, Co. Cavan. (Photo © Fiona Devaney & BEC Consultants) Irish Semi-natural Grasslands Survey: Counties Cavan, Leitrim, Longford & Monaghan - BEC Consultants 2009 Executive Summary In 2009, 239 sites and 1053 relevés in Cavan, Leitrim, Longford and Monaghan were surveyed as part of the Irish Semi-natural Grasslands Survey (ISGS). Eighty-six of these sites were associated with an NPWS conservation site (SAC, NHA, pNHA and SPA), but just four of the nine SACs in which Annex I grassland habitat was recorded list Annex I grassland habitats as a qualifying interest. Wet grassland was the most frequent semi-natural grassland habitat, recorded at 95.8% of sites and covering over 70% of the total area of grassland surveyed. Freshwater marsh was the least frequent and represented just 1% of the grassland surveyed in 2009. The most common EU Habitats Directive Annex I grassland habitat was Molinia meadows (6410), recorded at 7.9% of sites, followed by Nardus grasslands (6230), recorded at 5% of sites, and Festuco-Brometalia (6210), recorded at 4.1% of sites. The remaining Annex I grassland habitats – Lowland hay meadows (6510) and Hydrophilous tall herb communities (6430) – were only recorded at 3.3% of sites surveyed in 2009. 6410 covered the greatest area, at 62.4 ha, followed by 6510 (18.9 ha) and 6230 (17.6 ha). Calaminarian grassland (6130) was not recorded in 2009. Semi-natural grassland sites in Cavan, Leitrim, Longford and Monaghan were relatively large (median area 24.1 ha, ranging from 0.3 ha to 208.0 ha). Of the 33 sites that scored highly (a score of 40% or over) in the conservation evaluation, 23 were associated with an NPWS conservation site. Of the 21 sites that received high threat evaluations, nine were associated with an NPWS conservation site. The main habitats adjacent to surveyed sites were treelines/hedgerows and scrub. Unsurveyed semi- natural grassland and marsh occurred adjacent to a greater proportion of sites in 2009 than in 2008, indicating their presence within larger complexes of semi-natural grassland in the 2009 study area. A list of 47 primary areas of Annex I grassland habitat, representing the best quality Annex I grassland habitat recorded to date, was compiled for all grassland sites surveyed during ISGS 2007- 2009. Future years of ISGS will add further sites to this list, providing a focus for semi-natural grassland conservation in Ireland. The main threat recorded for Annex I grassland habitats surveyed in 2009 was encroachment/undergrazing, highlighting the urgency with which the problem of land abandonment needs to be tackled. The uplands of Leitrim and Cavan were found to contain many of the highest quality grasslands surveyed to date. The overall quality of each of the Annex I grassland habitats surveyed was Unfavourable – Bad, emphasising their vulnerability in Ireland and the urgency with which they need to be studied and monitored. The ISGS vegetation classification utilised hierarchical cluster analysis to analyse all relevé data recorded during 2009, plus relevé data recorded by the ISGS in 2007 and 2008. The classification contained four main groups. The two dry grassland groups, which accounted for 37.7% of the relevés, were named Plantago lanceolata – Festuca rubra and Potentilla erecta – Galium saxatile, based on the top indicator species. The wet grassland groups, which accounted for 62.3% of the Irish Semi-natural Grasslands Survey: Counties Cavan, Leitrim, Longford & Monaghan - BEC Consultants 2009 relevés, were named Agrostis stolonifera – Juncus effusus and Juncus acutiflorus – Calliergonella cuspidata. The four vegetation groups were further subdivided into 21 vegetation types, six more than in 2008. The addition of extra relevés in 2009 resulted in more vegetation types being identified, due partly to regional differences and partly to the redistribution of relevés within existing groups which led to further subdivision of groups. During 2009, the criteria for the evaluation of the conservation status and threats to grassland sites were refined as follows: • Positive indicator species were divided into high quality (H.Q.) and non-H.Q. indicators, with H.Q. indicators generally species found in high quality grassland habitats. • Three additional positive indicator species were included for the assessment of the structure and functions of the Annex I habitat Nardus grassland (6230). Irish Semi-natural Grasslands Survey: Counties Cavan, Leitrim, Longford & Monaghan - BEC Consultants 2009 Table of Contents Page 1 Introduction 1 1.1 General background 1 1.2 Vegetation studies of Irish grasslands 1 1.3 Classification of Irish grasslands 2 1.4 Conservation of Irish grasslands 3 1.5 Scope of this report 5 1.6 Study area 6 2 Methods 8 2.1 Site selection 8 2.2 General site survey 9 2.3 Relevé survey 13 2.4 Assessment of Annex I grassland 14 2.5 Ranking of sites using conservation and threat evaluations 18 2.6 Vegetation data analysis 21 3 Results 23 3.1 General site survey 23 3.2 Assessment of Annex I grassland 38 3.3 Ranking of sites using conservation and threat evaluations 44 3.4 Cluster analysis 47 4 Vegetation classification 50 5 Discussion 116 5.1 Summary data and the ranking of all surveyed sites 116 5.2 Assessment of Annex I grassland 120 5.3 Vegetation classification 126 5.4 Utilisation of the dataset 133 5.5 Concluding remarks 133 6 References 135 Irish Semi-natural Grasslands Survey: Counties Cavan, Leitrim, Longford & Monaghan - BEC Consultants 2009 List of Appendices Appendix 1: Maps showing the location of the 239 sites surveyed in 2009 Appendix 2: Summary information for each of the 239 sites surveyed in 2009 Appendix 3: Field sheets Appendix 4: Summary grassland habitat information for each of the 239 sites surveyed in 2009 Appendix 5: Annex I assessment indicator species and criteria Appendix 6: Structure and functions assessment scores for areas if Annex I grassland habitat surveyed from 2007 to 2009 Appendix 7: Future prospects categories Appendix 8: Future prospects assessment scores for sites surveyed from 2007 to 2009 Appendix 9: Annex I grassland habitat overall assessment scores for sites surveyed in 2009 Appendix 10: Overall assessment scores for the 47 primary areas of Annex I grassland habitat surveyed from 2007 to 2009 Appendix 11: Conservation scores for all sites surveyed from 2007 to 2009 calculated using method revised in 2009 Appendix 12: Threat scores for all sites surveyed from 2007 to 2009 Appendix 13: Top-ranked sites by County based on conservation score List of Figures Page Figure 1.1 Map of Ireland showing the survey area of counties Cavan, Leitrim, Longford and 6 Monaghan. Figure 3.1 Area in hectares of grassland habitats surveyed in 2009, differentiated by county. 24 Figure 3.2 Frequency of occurrence of different grassland habitats, differentiated by county. 25 Figure 3.3 Occurrence of NPWS conservation sites (pNHA/NHA, SAC and SPA) within the 26 survey. Figure 3.4 Frequency of non-grassland Fossitt (2000) habitats within all surveyed sites, 30 differentiated by county. Figure 3.5 Frequency of habitats occurring adjacent to surveyed sites, differentiated by county. 31 Figure 3.6 Frequency of different management regimes at sites, differentiated by county. 31 Figure 3.7 Frequency of grazing animals at sites, differentiated by county. 32 Figure 3.8 Frequency of different grazing levels and encroachment at sites, differentiated by 32 county. Figure 3.9 Frequency of occurrence of different types of damaging activity at sites, differentiated 33 by county. Figure 3.10 Frequency of agricultural activities recorded, differentiated by county. 34 Figure 3.11 Frequency of different geographical features associated with sites, differentiated by 34 county. Irish Semi-natural Grasslands Survey: Counties Cavan, Leitrim, Longford & Monaghan - BEC Consultants 2009 List of Tables Page Table 2.1 Summary matrix of the parameters and conditions required to assess the 14 conservation status of habitats (modified from Ryle et al . (2009)). Table 2.2 Criteria used in the calculation of the conservation score for each site. 19 Table 2.3 Criteria used in the calculation of the threat score for each site. 20 Table 3.1 The number of sites that were rejected and the reasons for rejection. 23 Table 3.2 The number of sites included in the survey that were in public and private ownership. 24 Table 3.3 Area in hectares of grassland habitats surveyed in 2009, differentiated by county.