Red Data Book for Guernsey J. Gilmour and C.T. David Guernsey Biological Records Centre 2020 1 Red Data Book for Guernsey J. Gilmour, BSc and C.T. David, PhD, BSc Guernsey Biological Records Centre 2020 Published by La Société Guernesiaise, Candie Gardens, St Peter Port, Guernsey 2020 © Guernsey Biological Records Centre, Raymond Falla House, Longue Rue, St Martin, GY1 6AF All base mapping © States of Guernsey i RED DATA BOOK FOR GUERNSEY PREFACE This book was started by the late Dr Charles David and then passed on to me, Jane Gilmour, to continue with once I joined the staff of the Guernsey Biological Records Centre (GBRC) in 2008. I wrote much of it, although it involved many discussions so it is a truly collaborative work. I stopped in 2012, when he suddenly and tragically died and I had to take on the running of the Centre. The Committee for the Environment and Infrastructure has kindly provided funding towards the completion of this document. For this I am most grateful, as this is a work that both Charles and I felt was dear to our hearts. I have updated as much information as possible to 2020, with help (see below). ACKNOWLEDGMENTS Dr Kim Gilmore, PhD for her editing, going through the book with an eagle eye and help with updating. Elizabeth Sweet, MSc for her review, as well as extensive and impressive formatting and help with updating. Jamie Hooper, BSc for his contributions on the birds. Dr Mel Broadhurst, PhD and Jessi Jennings, MSc for their comments and Dr Laura White, PhD for her contributions to the marine and intertidal sections. Chris Hurley for his review of the earlier draft of the book. The majority of photographs in this book are Charles David’s with a few of mine. We also thank to the following for their photographs: Kalerna, marsh cinquefoil; Kristian Peters, field forget-me-not; John Crellin, alternate water-milfoil; Christian Fischer, broad-leaved pondweed; Piet Spaans, male stickleback; Rob Cave, green ormer, blonde ray, small-eyed ray; Kirk Mottershead- internet, basking shark; Jeff De Longe, horned dung beetle; Wendy Bowman, Norwegian cockles. Jane Gilmour ii CONTENTS CONTENTS PREFACE ....................................................................................................................................................... II ACKNOWLEDGMENTS ................................................................................................................................... II SPECIES DESCRIPTION KEY .......................................................................................................................... XIV LATIN NAME .............................................................................................................................................. XIV ENGLISH NAME .......................................................................................................................................... XIV SHORE DOCK ............................................................................................................................................. XIV INTRODUCTION .......................................................................................................................................... 15 WHY IS THIS BOOK NEEDED? ........................................................................................................................................ 15 RED DATA BOOKS ....................................................................................................................................... 15 CONCEPT AND BACKGROUND........................................................................................................................................ 15 THE SIGNIFICANCE OF BIODIVERSITY ............................................................................................................................... 16 HABITATS ................................................................................................................................................... 17 WHAT IS A HABITAT? .................................................................................................................................................. 17 MICROHABITATS ........................................................................................................................................ 17 .................................................................................................................................................................. 19 SPECIES ...................................................................................................................................................... 20 EXCLUDED SPECIES ..................................................................................................................................................... 21 DATA SOURCES ........................................................................................................................................... 22 PAST LOSSES AND DECLINES ........................................................................................................................ 23 SALT MARSH.............................................................................................................................................................. 23 MARSHES ................................................................................................................................................................. 24 WETLAND ................................................................................................................................................................. 25 COASTAL .................................................................................................................................................................. 25 SIDE EFFECTS TO END OF GRAZING ................................................................................................................................. 27 AGRICULTURAL CHANGE .............................................................................................................................................. 27 UNIMPROVED DRY GRASSLAND ..................................................................................................................................... 28 FISHING .................................................................................................................................................................... 29 SAND DUNE .............................................................................................................................................................. 29 PLANTING OF NON-NATIVE SPECIES ................................................................................................................................ 30 CURRENT THREATS ..................................................................................................................................... 30 GENERAL .................................................................................................................................................................. 30 MARINE ................................................................................................................................................................... 31 PERMANENT GRASSLANDS ........................................................................................................................................... 31 THE FUTURE ............................................................................................................................................... 31 TABLE 1. AREAS OF VEGETATION TYPES IN GUERNSEY FROM IDC PHASE 1 HABITAT SURVEYS .................................................. 33 iii CONTENTS Marine .............................................................................................................................................................. 34 Beaches and cliffs ............................................................................................................................................. 34 Terrestrial ......................................................................................................................................................... 34 BIRDS AT RISK ................................................................................................................... 192 HABITAT......................................................................................................................................................36 TYPICAL PLANTS ......................................................................................................................................................... 36 TYPICAL ANIMALS ....................................................................................................................................................... 37 MANAGEMENT REQUIREMENTS ..................................................................................................................38 THREATS TO THIS HABITAT ..........................................................................................................................38 WESTERN GORSE .........................................................................................................................................39 LOUSEWORT ...............................................................................................................................................39 ORANGE BIRD’S-FOOT .................................................................................................................................39