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Inventory Methods for Raptors Inventory Methods for Raptors Standards for Components of British Columbia's Biodiversity No. 11 Prepared by Ministry of Sustainable Resource Management Environment Inventory Branch for the Terrestrial Ecosystems Task Force Resources Inventory Committee October 2001 Version 2.0 © The Province of British Columbia Published by the Resources Inventory Committee National Library of Canada Cataloguing in Publication Data Main entry under title: Inventory methods for raptors [computer file] (Standards for components of British Columbia’s biodiversity; no. 11) Available on the Internet. Issued also in printed format on demand. Previously published: Standard inventory methodologies for components of British Columbia biodiversity. Raptors. 1997 [Version 1.1] ISBN 0-7726-4619-8 1. Birds of prey - British Columbia. 2. Bird populations - British Columbia. 3. Ecological surveys - British Columbia - Methodology. I. British Columbia. Ministry of Sustainable Resource Management. Environment Inventory Branch. II. Resources Inventory Committee (Canada). Terrestrial Ecosystems Task Force. III. Series. QL685.5.B7I58 2001 333.95’8911’09711 C2001-960239-1 Additional Copies of this publication can be purchased from: Government Publications Centre Phone: (250) 387-3309 or Toll free: 1-800-663-6105 Fax: (250) 387-0388 www.publications.gov.bc.ca Digital Copies are available on the Internet at: http://www.for.gov.bc.ca/ric Biodiversity Inventory - Raptors Preface This manual, version 2.0, is a revised and improved presentation of standard methods for inventory of raptors in British Columbia at three levels of inventory intensity: presence/not detected (possible), relative abundance, and absolute abundance. The manual was compiled by the Terrestrial Ecosystems Task Force, under the auspices of the Resources Inventory Committee (RIC). The objectives of the working group are to develop inventory methods that will lead to the collection of comparable, defensible, and useful inventory and monitoring data for the species component of biodiversity. This manual is one of the Standards for Components of British Columbia’s Biodiversity (CBCB) series that present standard protocols designed specifically for groups of species with similar inventory requirements. The series includes an introductory manual (Species Inventory Fundamentals No. 1) which describes the history and objectives of RIC, and outlines the general process of conducting a species inventory according to RIC standards, including selection of inventory intensity, sampling design, sampling techniques, and statistical analysis. The Species Inventory Fundamentals manual provides important background information and should be thoroughly reviewed before commencing with a RIC wildlife inventory. RIC standards are also available for vertebrate taxonomy (No. 2), animal capture and handling (No. 3), voucher collection (No. 4), and radio-telemetry (No. 5). Field personnel should be thoroughly familiar with these standards before engaging in field inventories which may involve any of these activities. Standard dataforms are required for all RIC species inventory. Survey-specific dataforms accompany most manuals while general wildlife inventory forms are available in Species Inventory Fundamentals No. 1 [Forms]. This is important to ensure compatibility with provincial data systems, as all information must eventually be included in the Species Inventory (SPI) Datasystem (visit the website at http://srmwww.gov.bc.ca/rib/wis/spi/). It is recognized that development of standard methods is necessarily an ongoing process. The CBCB manuals are expected to evolve and improve quickly over their initial years of use. Field-testing is a vital component of this process and feedback is essential. Comments and suggestions can be forwarded by contacting: Conservation Data Centre Ministry of Sustainable Resource Management P.O. Box 9344, Station Prov Govt Victoria, BC V8W 9M1 Email: [email protected] October 2001 iii Biodiversity Inventory - Raptors Acknowledgments Funding of the Resources Inventory Committee work, including the preparation of this document, is provided by the Corporate Resource Inventory Initiative (CRII) and by Forest Renewal BC (FRBC). Preliminary work of the Resources Inventory Committee was funded by the Canada-British Columbia Partnership Agreement of Forest Resource Development FRDA II. The Resources Inventory Committee consists of representatives from various ministries and agencies of the Canadian and the British Columbia governments as well as from First Nations peoples. RIC objectives are to develop a common set of standards and procedures for the provincial resources inventories, as recommended by the Forest Resources Commission in its report “The Future of our Forests”. For further information about the Resources Inventory Committee and its various Task Forces, please access the Resources Inventory Committee Website at: http://www.for.gov.bc.ca/ric. Terrestrial Ecosystems Task Force All decisions regarding protocols are the responsibility of the Resources Inventory Committee. The current version of this manual was the result of the hard work of Frank Doyle (Wildlife Dynamics Consulting). Section 5, species accounts and survey notes, was largely based on materials adapted from the RIC Raptors Inventory course compiled by Michael Setterington (AXYS Environmental Consulting Ltd.) and Frank Doyle. Statistical review comments were provided by John Boulanger (Integrated Ecological Research). Helpful comments were provided by Erica McCLaren, Laura Darling, Andy Stewart and Ross Vennesland The Components of British Columbia’s Biodiversity series is currently edited by Leah Westereng. October 2001 v Biodiversity Inventory - Raptors Table of Contents Preface ...........................................................................................................................iii Acknowledgments ............................................................................................................v 1. INTRODUCTION ....................................................................................................1 2. INVENTORY GROUP .............................................................................................3 3. GENERAL PROTOCOL...........................................................................................7 3.1 Survey Standards ................................................................................................. 11 3.1.1 Personnel..................................................................................................... 11 3.1.2 Weather....................................................................................................... 11 3.1.3 Time of Year ............................................................................................... 12 3.1.4 Time of Day................................................................................................. 13 3.1.5 Habitat Data Standards ................................................................................. 13 3.1.6 Conducting surveys on foot vs other transportation ......................................... 13 3.1.7 Sign: Prey Remains, Pellets, Whitewash, and Feathers.................................... 14 3.1.8 Data Entry ................................................................................................... 16 3.1.9 Data Analysis ............................................................................................... 16 3.1.10 Survey Design Hierarchy .............................................................................. 16 3.2 Inventory Surveys ................................................................................................ 18 3.2.1 Species-specific Inventory Survey Information............................................... 18 3.3 Call Playback Surveys ......................................................................................... 19 3.4 Foot Surveys ....................................................................................................... 27 3.5 Ground Nest Search............................................................................................. 30 3.6 Roadside Surveys ................................................................................................ 32 3.7 Standwatches ...................................................................................................... 35 3.8 Migration Surveys ............................................................................................... 36 October 2001 vii Biodiversity Inventory - Raptors 3.9 Aerial Surveys ..................................................................................................... 37 3.10 Boat Surveys ................................................................................................... 42 4. DATA ANALYSIS................................................................................................. 45 4.1 Presence/not detected........................................................................................... 45 4.2 Relative Abundance............................................................................................. 45 4.3 Absolute Abundance............................................................................................ 47 5. SPECIES ACCOUNTS & SURVEY NOTES ........................................................... 49 5.1 Introduction......................................................................................................... 49
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