RA Tere are increasing demands for high quality information on the numbers, distribution and population trends of birds of prey. Tis book, now in its third edition, aims to promote best practice for feldwork, drawing on the knowledge and experience of more than 300 raptor PT specialists, especially members of the Raptor Study Groups. Incorporating new information and feedback from raptor feldworkers on the second edition, it covers all birds of prey (diurnal ORS raptors and owls) which occur regularly in Britain and Ireland. Introductory sections provide a Raptors history of raptor monitoring, background to survey techniques and design, and advice on good A Field Guide For Surveys And Monitoring practice for feldcraf. Detailed descriptions of survey methods for individual species follow, supplemented by photographic identifcation guides for raptor feathers and illustrations of
the growth of raptor chicks for a range of species. Tere is an updated section on population A estimates for raptors in Britain and Ireland, contacts for organisations involved in raptor FIELD GUIDE FOR SU monitoring, and examples of data recording forms. Te accompanying CD describes the use of raptor calls to aid species identifcation and interpret behaviour. Tis highly successful and authoritative guide has been written and edited by a team from the Scottish Raptor Monitoring Group. It has been funded by Scottish Natural Heritage with assistance from other Statutory Nature Conservation Agencies in Britain and Ireland, and voluntary conservation bodies concerned with birds of prey. “People studying raptors should fnd this book indispensable…” Professor Ian Newton FRS
“Tis ‘how-to’ book should be bought and read by all R VEY new and not-so-new practitioners in the feld”
Keith Bildstein S
A ND M O NIT OR IN G Brian Etheridge Des J Chris WernhamChris Helen Riley on Hardey Humphrey Crick T ird edition T ompson
Jon Hardey Humphrey Crick Chris Wernham Helen Riley Brian Etheridge Des Tompson Price £18.99 Tird edition
Raptors: a field guide for surveys and monitoring
THIRD edition
Jon Hardey Humphrey Crick Chris Wernham Helen Riley Brian Etheridge Des Tompson
THE STATIONERY OFFICE: EDINBURGH This book is dedicated to the memory of:
Derek Ratcliffe (1929 – 2005) Pioneer of systematic surveys of raptors, Derek was a good friend and mentor to many people who have studied these birds. Through his work on pesticides and protected areas, Derek was a leader of the statutory nature conservation movement in Britain during the 1970s and 1980s. He published classic books on the peregrine, the raven and upland birds.
© Scottish Natural Heritage 2013
First published in 2006 by The Stationery Office Limited 20 Rutland Square, Edinburgh EH1 2BW
Reprinted March 2007 Reprinted September 2007 Second edition September 2009 Third edition November 2013 Reprinted July 2014
Applications for reproduction should be made to Scottish Natural Heritage, Great Glen House, Leachkin Road, Inverness IV3 8NW
British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library
ISBN 978 0 11 497360 5
“This excellent manual will facilitate the standardisation of research techniques and ensure that the collection of data meets the highest possible standards – not just in Britain and Ireland, but across Europe, where the subject matter is equally relevant.” Ibis, July 2007
“The publishers deserve to be congratulated on creating a thoroughly useful publication...if you’d like to see more raptors and understand their lifestyles, you should buy it.” Birdwatch, July 2007
The cover image freezes the moment as a female hen harrier comes in to land or perhaps to pounce on prey, capturing the striking beauty of this upland raptor with its tawny plumage and distinctive white rump or ‘ringtail’ (very different to the grey, white and black of the male – shown on the frontispiece). A controversial species, due to its association with moorland and the inclusion of red grouse in its diet, the hen harrier is still considered at high risk of illegal persecution in some areas of Britain and Ireland. Robust monitoring is key to understanding the status of this species and the real reasons behind its changing fortunes. Photo: Laurie Campbell
We are delighted to be able to reproduce two paintings by the late Donald Watson, taken from his book, The Hen Harrier, published in 1977. These comprise a male and female hen harrier in forest breeding habitat (frontispiece) and a pair about to engage in a food pass (the CD cover and label). Donald inspired people through his evocative landscape paintings and bird illustrations, and his writing. The paintings are reproduced with kind permission of T & A D Poyser, A&C Black and the Watson family. Foreword by Ian Newton ix Preface x Acknowledgements xi The authors xiii Editorial note xiv #ONTENTS Part 1 Introduction 1 1. Introduction 2 1.1 Why monitor raptors? ...... 2 1.2 The development of raptor monitoring in Britain and Ireland ...... 3 1.2.1 Raptor Study Groups ...... 3 1.2.2 The UK Raptor Working Group...... 4 1.2.3 The Scottish Raptor Monitoring Scheme...... 5 1.3 International perspectives on raptor monitoring...... 6 1.4 The status of raptors in Britain and Ireland...... 6 1.5 A survey and monitoring guide for raptors...... 7
2. Survey, surveillance and monitoring 10 2.1 Definitions...... 10 2.2 Choice of survey methods ...... 11 2.2.1 Counts of occupied home ranges and active nests ...... 11 2.2.2 Alternative survey methods: transects and point counts ...... 12 2.3 Surveys and monitoring in Britain and Ireland ...... 14
3. Population estimates 16 3.1 Population sampling ...... 16 3.2 Breeding birds ...... 16 3.2.1 Occupied sites ...... 17 3.2.2 Territorial pairs...... 17 3.2.3 Breeding pairs ...... 17 3.3 Non-breeding birds ...... 17
4. Breeding season parameters 19 4.1 Home range and territory ...... 19 4.2 Nest sites, nesting ranges and alternatives ...... 19
a field guide for surveys and monitoring
2APTORS V 4.3 Nests ...... 20 4.4 Occupancy ...... 20 4.5 Proof of breeding, breeding success and fledging ...... 21 4.6 Productivity ...... 22 4.7 Breeding failure ...... 22 4.7.1 Natural reasons for non-breeding or failure...... 22 4.7.2 Persecution...... 23
5. Identification and breeding behaviour of raptors 24 5.1 Identification of raptors ...... 24 5.2 Identifying raptor signs ...... 24 5.2.1 Kills ...... 24 5.2.2 Pellets...... 25 5.2.3 Droppings ...... 25 5.2.4 Feathers ...... 25 5.3 Breeding behaviour of raptors ...... 26 5.3.1 Display ...... 26 5.3.2 Egg laying and incubation ...... 27 5.3.3 Hunting and feeding...... 27 5.3.4 Interpretation of behaviour ...... 28 5.4 Vocalisations ...... 28
6. Additional techniques for studying raptors 29 6.1 Ringing ...... 29 6.2 Wing-tagging ...... 30 6.3 Remote tracking ...... 31 6.3.1 Radio-tracking ...... 31 6.3.2 Satellite tracking ...... 32 6.3.3 PIT tags ...... 33 6.4 Biological and chemical ‘markers’ ...... 33 6.4.1 Genetic markers ...... 33 6.4.2 Chemical markers ...... 34 6.5 Nomograms ...... 35 6.5.1 Egg density...... 35 6.5.2 Chick growth ...... 36 6.6 Nest boxes...... 37
7. Good practice for fieldwork 39 7.1 Legal considerations ...... 39 7.1.1 Licences ...... 39 7.1.2 Access ...... 42 7.2 Minimising disturbance and good field craft ...... 44
a field guide for surveys and monitoring