SNH Commissioned Report 479: The use of camera for future monitoring efforts of the Scottish wildcat. Main findings Camera trapping did capture “wild-living” cats in an area where ... Camera trap

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  • Scottish Natural HeritageCommissioned Report No. 479

    The use of camera trapping as a method to survey for the Scottish wildcat

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    C O M M I S S I O N E D R E P O R T

    Commissioned Report No. 479

    The use of camera trapping as a method to survey for the Scottish wildcat

    For further information on this report please contact:

    Jenny Bryce Scottish Natural Heritage Great Glen House INVERNESS IV3 8NW Telephone: 01463-725000 E-mail: jenny.bryce@snh.gov.uk

    This report should be quoted as:

    Kilshaw, K. & Macdonald, D.W. (2011). The use of camera trapping as a method to survey for the Scottish wildcat. Scottish Natural Heritage Commissioned Report No. 479.

    This report, or any part of it, should not be reproduced without the permission of Scottish Natural Heritage. This permission will not be withheld unreasonably. The views expressed by the author(s) of this report should not be taken as the views and policies of Scottish Natural Heritage.

    Scottish Natural Heritage 2011.

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    The use of camera trapping as a method to survey for the Scottish wildcat

    Commissioned Report No. 479 (iBids No. 479) Contractor: Kerry Kilshaw and David Macdonald Year of publication: 2011 SUMMARY The Scottish wildcat, Felis silvestris grampia, is currently endangered by a variety of factors including hybridisation with and disease transmission from the feral cat, F. catus, habitat loss and fragmentation, and persecution (e.g. Macdonald et al., 2004). To assess the status of the population, the Scottish wildcat needs rigorous monitoring of population densities and demographic trends. Most surveys to date have used road traffic accident surveys, live trapping and/or questionnaires and interviews to collect data. The aim of this project was to determine whether camera trapping could be an effective method for future monitoring efforts of the Scottish wildcat. Main findings Camera trapping did capture wild-living cats in an area where they were known to occur based on

    previous sightings

    A total of 13 individual wild-living cats were captured; 4 wildcats and 9 hybrids. Individuals could be identified by their pelage markings

    No feral cats were caught on camera

    No cat carcasses were found on roads surrounding and bisecting the study area during the trapping period

    No wild-living cats were seen by the keepers on the estate during the trapping period

    The use of bait did result in increased capture rates

    The use of Valerian lure did not result in increased capture rates and the development or identification of a suitable scent lure should be pursued

    The study indicated that some changes should be made to the camera trapping method in order to increase the capture success; these are to reduce the space between camera trap stations to 1km, use of bait to attract cats to the cameras and increase the survey length to 2 months or 60 days.

    Density estimates could be obtained using the data collected and these estimates were comparable to those from other studies indicating that camera trapping could be a useful tool for monitoring of the Scottish wildcat.

    COMMISSIONED REPORT

    Summary

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    For further information on this project contact: Jenny Bryce

    Tel: 01463 725249 For further information on the SNH Research & Technical Support Programme contact:

    DSU (Policy & Advice Directorate), Scottish Natural Heritage, Great Glen House, Inverness, IV3 8NW. Tel: 01463 725000 or research @snh.gov.uk

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    1. INTRODUCTION ................................................................................................................................................... 1

    2. AIMS AND OBJECTIVES ..................................................................................................................................... 2

    3. METHODOLOGY .................................................................................................................................................. 3 3.1. Study area ...................................................................................................................................................... 3 3.2. Camera trapping............................................................................................................................................. 4 3.3. Camera trap surveys...................................................................................................................................... 5 3.4. Wildcat identification....................................................................................................................................... 6 3.5. Road Traffic Accident Surveys....................................................................................................................... 9

    4. DATA ANALYSIS................................................................................................................................................. 9 4.1. Trap nights (TN) ............................................................................................................................................. 9 4.2. Capture events ............................................................................................................................................... 9 4.3. Capture frequency.......................................................................................................................................... 9 4.4. Capture probability and abundance estimate: Programme CAPTURE ......................................................... 9 4.5. Density estimates ......................................................................................................................................... 10

    4.5.1. CAPTURE............................................................................................................................................. 10 4.5.2. SPACECAP .......................................................................................................................................... 11

    5. RESULTS ............................................................................................................................................................ 14 5.1. Survey 1: Camera trapping without bait ....................................................................................................... 15 5.2. Survey 2: Camera trapping with bait ............................................................................................................ 15 * neck stripes that couldnt been seen clearly were given a more conservative score....................................... 18 5.3. Capture probability and abundance estimate: Programme CAPTURE ....................................................... 19 5.4. Density estimates ......................................................................................................................................... 22 5.4.2. SPACECAP............................................................................................................................................... 22

    6. DISCUSSION AND RECOMMENDATIONS....................................................................................................... 23 6.1. Number of camera traps, camera station layout and survey length ............................................................ 23 6.2. Use of bait/lure ............................................................................................................................................. 24 6.3. Abundance and Density Estimates .............................................................................................................. 25 6.4. Layout and height of camera traps............................................................................................................... 26 6.5. Battery duration and checking the camera traps ......................................................................................... 26

    7. ACKNOWLEDGEMENTS ................................................................................................................................... 27

    8. REFERENCES .................................................................................................................................................... 28

    9. APPENDIX 1: Height of camera traps and distance from each other, bait or lure...................................... 32

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    1. INTRODUCTION The Scottish wildcat (Felis silvestris grampia, Miller 1907) is Britains only surviving native felid (Macdonald et al., 2004) and is currently classified as Least Concern (IUCN, 2011). Previously widespread across the UK, the Scottish wildcat is now thought to be limited to the north of Scotland (Balharry & Daniels, 1998; Davies et al., 2010) with a population estimate possibly as low as 400 individuals remaining (Macdonald et al., 2004). The decline of the wildcat has been attributed partially to habitat loss, in particular loss of forested areas, and partially to hunting for its fur and persecution (Kitchener, 1995). The development of sporting estates in Scotland from the mid-19th century increased the rate of decline (Langley & Yalden, 1977; Tapper 1992). The current threats are thought to be mainly hybridisation with and disease transfer from domestic/feral cats (F. catus L. 1758), habitat loss and human persecution (Hubbard et al., 1992; McOrist et al., 1991; Nowell & Jackson, 1996). As a species vulnerable to extinction, monitoring of numbers of Scottish wildcat is required with sufficient sensitivity in order to accurately detect changes and trends in populations. To date a combination o