This DATSETNAMEreadme.txt file was generated on 2021-03-19 by Tarnya Cox GENERAL INFORMATION 1. Title of Dataset: Warren and entrance detections by thermal imager 2. Author Information A. Principal Investigator Contact Information Name: Tarnya Cox Institution: New South Wales Department of Primary Industries Address: 1447 Forest Road, Orange, NSW 2800 Australia Email: tarnya.cox@dpi.nsw.gov.au B. Associate or Co-investigator Contact Information Name: Robert Matthews Institution: Heli Surveys Address: Jindabyne Airport, Jindabyne NSW 2627 Australia Email: rob@helisurveys.com.au 3. Date of data collection (single date, range, approximate date): November 2017 - June 2018 4. Geographic location of data collection: Orange New South Wales 2800 and Hay New South Wales 2711, Australia 5. Information about funding sources that supported the collection of the data: Australian Government Department of Agriculture and Water Resources Agricultural Competitiveness White Paper - Control tools and technologies for established pest animals and weeds program. SHARING/ACCESS INFORMATION 1. Licenses/restrictions placed on the data: None 2. Links to publications that cite or use the data: Cox et al, 2021, Hot Stuff in the Bushes: thermal imagers and the detection of burrows in vegetated sites. Ecology and Evolution 3. Links to other publicly accessible locations of the data: https://doi.org/10.22541/au.160027530.08798648 4. Links/relationships to ancillary data sets: NA 5. Was data derived from another source? No 6. Recommended citation for this dataset: Cox TE, Matthews R, Halverson G and Morris S. 2021. Warren and entrance detections by thermal imager DATA & FILE OVERVIEW 1. File List: Table of detections of active rabbit warren entrances located visually and with comparison of two different quality thermal imagers 2. Relationship between files, if important: NA 3. Additional related data collected that was not included in the current data package: NA 4. Are there multiple versions of the dataset? No METHODOLOGICAL INFORMATION 1. Description of methods used for collection/generation of data: Please see the methods section in https://doi.org/10.22541/au.160027530.08798648 for a full description of how data was collected. Warren surveys Determining which warren entrances belong to which warrens can be challenging in high density rabbit populations. For the purposes of this research, an entrance was part of the same warren if it was within 5m of another entrance. When an entrance was detected that was more than 5m away from another entrance, this was deemed to be part of a new warren. Single entrances that were >5m away from other entrances were considered a single-entrance warren. Warrens were regarded as active when one or more entrance had signs of use. This includes a lack of vegetation growing in the entrance, the presence of freshly excavated soil, fresh scat and/or the presence of rabbit footprints. Warrens where all entrances were covered in either debris (leaves and sticks), with cobwebs and with hard crusted soil were considered inactive. No further validation (e.g. excavation or trapping) was undertaken to confirm warren activity status. All thermal imager surveys were conducted in the morning before first light to maximise the temperature differential between warren entrances and the surrounding terrain. All sites were visually inspected for rabbit warrens (active and inactive) on foot during the day (prior to the thermal survey) and all identified warrens were mapped with their GPS locations recorded. The ground and aerial surveys were independent, i.e. the thermal imager transects were designed prior to visual inspection. In Part 1 we determined whether active rabbit warrens could be detected with a thermal imager. We flew the drone with the Jenoptik imager directly to the warren locations. In Part 2 we compared a professional imager (Vayu) to a consumer imager (Zenmuse). We established parallel flight transects to allow complete coverage of the area being investigated and to mimic the actual survey method that should be employed to search for warrens. We undertook visual counts of warrens and warren entrances in Part 2. Visual counts were undertaken upon arrival and before the drone flights. Parallel line transects approximately 10m apart were walked and all warrens and associated entrances were recorded. Once imagery from the drone flights were processed (see below), we undertook an additional visual inspection on foot to confirm entrances identified from the thermal imagery and to identify any false-positives or -negatives. 2. Methods for processing the data: We downloaded the footage from the thermal imagers to an external hard drive and reviewed the footage from this drive using VLC media player 3.0.8. We recorded observations in a custom-built Microsoft Excel (Microsoft Corporation 2018) workbook which utilised the drone’s tracklog to georeference observation locations. This file was then exported as a KML file and viewed in Google Earth Pro (Google Earth Pro 2019) to aid in comparison between thermal imager and visual inspection detections. Where transect imagery overlapped, double observations of warren entrances were removed from the worksheet before analysis. If a warren complex was identified on one transect, and additional warren entrances were identified on the immediate next transect in the same location, then a determination was made on whether these entrances belonged to the same warren or constituted a new warren. This ensured warren counts were not over-estimated. Warrens were classified by the amount of vegetation present that was likely to obscure entrances. Warrens with no vegetation present were classified as “open”, warrens obscured by vegetation (e.g. entrances were beneath shrubs) were classified as “vegetated” and warrens that had entrances in the open and obscured by vegetation were classified as “mixed”. These classifications also applied to the entrances associated with that warren for analysis (i.e. individual entrances in “mixed” warrens were not further classified into “open” or “vegetated” categories for analysis). DATA-SPECIFIC INFORMATION FOR: Warren and entrance detections by thermal imager 1. Number of variables: 205 2. Number of cases/rows: 41 3. Variable List: vegetation: whether warren entrances were classified as being obscured by vegetation (v), in open habitat (o), or a combination with some entrances obscured by vegetation (m) warren: identifier for the warren visual: how many entrances for that warren were located by visual search vayu: how many entrances for that warren were identified with thermal footage collected by the Vayu zenmuse: how many entrances for that warren were identified with thermal footage collected by the Zenmuse 4. Missing data codes: NA 5. Specialized formats or other abbreviations used: NA