The Status of Red Grouse in Ireland and the Effects of Land Use, Habitat and Habitat Quality on Their Distribution
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The status of Red Grouse in Ireland and the effects of land use, habitat and habitat quality on their distribution. Results of the national Red Grouse Survey 2006-2008 Irish Wildlife Manuals No. 50 The status of Red Grouse in Ireland and the effects of land use, habitat and habitat quality on their distribution. Results of the national Red Grouse Survey 2006-2008 Cummins, S. 1, Bleasdale, A. 2, Douglas, C., 2 Newton, S. 1, O’Halloran, J. 3 & Wilson, H. J. 2 1BirdWatch Ireland , 2 National Parks & Wildlife 3 Department of Zoology, Unit 21, Block D, Service , Ecology & Plant Science, Bullford Business Campus, Department of Environment University College Cork , Kilcoole, Heritage and Local Distillery Fields, Co. Wicklow. Government (EHLG), North Mall, Cork City. www.birdwatchireland.ie 7 Ely Place, Dublin 2. www.ucc.ie www.npws.ie Citation : Cummins, S., Bleasdale, A., Douglas, C., Newton, S., O’Halloran, J. & Wilson, H.J. (2010) The status of Red Grouse in Ireland and the effects of land use, habitat and habitat quality on their distribution. Irish Wildlife Manuals , No. 50. National Parks and Wildlife Service, Department of the Environment, Heritage and Local Government, Dublin, Ireland. Cover photo: Adult Male Red Grouse (© Mike Brown) Irish Wildlife Manual Series Editors: F. Marnell & N. Kingston © National Parks and Wildlife Service 2010 ISSN 1393 - 6670 Red grouse survey 2006-08 CONTENTS EXECUTIVE SUMMARY ...........................................................................................................................................................6 ABBREVIATIONS & COMMON TERMS USED ........................................................................................................................7 PARTNERSHIP .........................................................................................................................................................................9 ACKNOWLEDGEMENTS .........................................................................................................................................................9 1.0 INTRODUCTION ..............................................................................................................................................................10 1.1 Decline in numbers and range..........................................................................................................................10 1.2 EU Judgment ..........................................................................................................................................................10 1.3 Climate change ......................................................................................................................................................11 1.4 Taxonomic status ..................................................................................................................................................11 1.5 Previous studies ....................................................................................................................................................11 1.6 Habitat preferences ..............................................................................................................................................11 1.7 Territory establishment and habitat management ......................................................................................12 1.8 Conservation value...............................................................................................................................................12 AIMS:...................................................................................................................................................................................12 2.0 METHODS .......................................................................................................................................................................13 2.1 Sampling Range ....................................................................................................................................................13 2.2 Preliminary reconnaissance ...............................................................................................................................17 2.3 Regional Classification .......................................................................................................................................18 2.4 Survey Design and Sampling Strategy...........................................................................................................19 2.5 Survey Units...........................................................................................................................................................19 2.6 Survey Equipment................................................................................................................................................19 2.7 Methods Used........................................................................................................................................................20 2.7.1 Counts with tape-playback...............................................................................................................................20 2.7.1.1 Tape-playback transect methodology...............................................................................................21 2.7.1.2 Effectiveness of tape-playback............................................................................................................22 2.7.1.3 Study Sites for the Standardised tape-playback survey................................................................22 2.7.1.4 Survey Period for Tape-playback.......................................................................................................22 2.7.1.5 Survey Methods.....................................................................................................................................22 2.7.2 Counts using dogs............................................................................................................................................22 2.7.3 Tape-playback versus dog counts ....................................................................................................................23 2.7.4 Casual Sightings and supplementary records database.................................................................................23 2.7.5 Estimating species range..................................................................................................................................24 2.7.6 Population estimates.........................................................................................................................................24 2.7.6.1 Methods for estimation ........................................................................................................................24 2.7.6.2 Local population estimates..................................................................................................................24 2.7.7 Effect of elevation on patterns of distribution.................................................................................................25 2.7.8 Landowner permission .....................................................................................................................................25 2.7.9 Unsuitable areas ...............................................................................................................................................25 2.7.10 Health and Safety ...........................................................................................................................................25 2.7.11 Response rate ..................................................................................................................................................25 2.7.11.1 Tape-playback methods.....................................................................................................................25 2.7.11.2 Time of day ...........................................................................................................................................25 2.8 A survey of Red Grouse ( Lagopus lagopus ) habitat in Ireland 2007 – 2008...........................................26 2 Red grouse survey 2006-08 2.9 Data Analyses ....................................................................................................................................................... 26 2.9.1 Statistical Software.......................................................................................................................................... 27 3.0 RESULTS ..................................................................................................................................................................... 27 3.1 Survey outcome .................................................................................................................................................... 27 3.1.1 Overview .......................................................................................................................................................... 27 3.1.2 Survey coverage ............................................................................................................................................... 27 3.1.3 Responses to tape-playback.............................................................................................................................. 27 3.1.4 Comparison