NON INVASIVE POUCH MONITORING OF THE SPOTTED-TAILED QUOLL DASYURUS MACULATUS GRACILIS USING CAMERA TRAPS ALBERTO N. VALE Introduction Traditional data collection of gender and pouch young of mammal species, like the Quolls, has been achieved by using the stressful and invasive method of cage trapping and handling animals, often including sedation. Recent studies (de Bondi, White, Stevens and Cooke, 2010) showed that camera trapping is now often more cost effective and more useful than trapping for wildlife detection. Camera traps (motion sensor cameras) are now widely used to monitor, survey and sample a variety of arboreal and ground-dwelling species of wildlife. (Meek, Ballard and Fleming, 2012) Restricted initially by image resolution, unsuitable minimum focal lengths, slow trigger mechanisms, new improvements in motion sensor technology, has seen cameras achieving remarkable improvement in sensor trigger response, with fixed or manual focal range, no glow illumination [“no-glow” flash feature are cameras equipped with black LED's which are totally invisible to not only game animals but humans as well], interchangeable lenses and higher resolution imagery. Integrating these technological advances, a new non-invasive method of wildlife monitoring, WildCAM Australia® has developed “Quoll C”, and the more advanced Quoll C MKII, camera systems that now allow close-up recordings of the underside of wild mammals, using a scented attractant to lure the target species. The system has been successful in identifying spotted-tailed Quolls, including their gender and stage of development of their pouch young [Fig 1], changing what was previously an intrusive and stressful cage trapping method, to now provide an easily deployed remote and relatively non invasive method for studying Quolls. Design and Procedure The Australian Quoll Conservancy (AQC) has previously successfully used camera traps, to identify individual northern spotted-tailed Quolls by recording their unique pattern of body spots. However the methods reported here have extended this work to provide gender identification monitoring of female pouch and teat development and growth of pouch young during the Quoll breeding season.
Fig 1 Quoll C Flat tray capturing the distended and relaxed genitalia of a breeding female quoll.
The initial prototype was created in June 2015, by WildCAM Australia® using small High Definition GoPro cameras, with 128Gb Micro SD cards [One megabyte (MB) is made up of 1,024 kilobytes (KB). The next measurement up is a gigabyte (GB), which is made up of 1024MB], recording subjects at 1080p [known as Full HD 1080 horizontal lines of vertical resolution; the p stands for progressive scan] and 2.7K [resolution of 2704x1524] high definition video rates. The small size cameras allowed for compact field deployment including the March 2018
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maneuverability and flexibility of POV angles [“point of view” used especially in describing a method of shooting a scene or film that expresses the best attitude of the subject in a scene] and manual focal ability, crucial to the size of the subject and clear identification. The construction of a rectangular low profile Perspex tray [Fig 2] with a detachable clear Perspex window was placed horizontally on the ground, the size of which allowed some flexibility on the species to be sampled. For nighttime operation the
Fig 2 QuollC with POV cameras set up
apparatus was fitted with an auxiliary light source. Commercially available rechargeable LED lights were converted into IR illumination floodlights [Fig 3] controlled by a light sensor to switch off during daylight hours. Two cameras with manual adjustable focal length, were inserted into the apparatus. One camera was converted to full light spectrum to capture the subject in complete darkness, while the other non modified camera, remained active during the daylight hours. Each camera had an independent power supply, consisting of two commercially available 10,400 mHa power banks, [a milliampere hour is a unit of electric charge, and it's the most common way to express the capacity of small batteries, the bigger the number, the more power measure for charge, a battery can hold] each modified to supply a continuous regulated voltage of 4.5volts as per cameras power specifications. The power banks would remain operational and with enough power to sustain a continuous power supply for 4 days. Each camera was individually operated by external controller boards, including available video scripts. Cameras were triggered when animals in range, activated a PIR [(Passive InfraRed sensor) a device used to detect motion by receiving infrared radiation. When a person walks past the sensor, it detects a rapid change of infrared energy and sends a signal] or X-Band motion sensors [a band of frequencies in the microwave radio region of the electromagnetic spectrum, used commonly in radars], setting off High Definition video recording at pre-selectable durations. Animals standing on the window of the Perspex tray [Fig 2] would face in the constrained and restricted access way to the lure, thus triggering the motion sensors, and a high definition video would be obtained of their undersides for a predetermined time. Results The prototype performance of WildCAM Australia® “Quoll C” Camera Systems successfully captured the underside of several Spotted-tailed Quoll genitalia, thus simplifying the colony gender ratio findings, including full views of bodily fluids discharges. Other underside views of by-catch, were Brush Turkeys Alectura lathami and Bush Rats Rattus fuscipes.
Fig 3 Infra Red light illumination example for Quoll C & Quoll C MKII
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motion sensor cameras for this new system apparatus were sourced and acquired from a generic commercial brand, costing less than $200 each (bulk pricing). These cameras were also found to have a required minimum focal range of 400 mm to the subject. This extremely portable (one person deployment requirement) and affordable system is, although not delivering the same High Definition sharpness and resolution of the initial prototype cameras, costs one third of its prototype price, making it an affordable compromise. Discussion Camera trapping is increasingly being adopted in Australia as a wildlife research and monitoring tool, this new method is allowing the recording of visual images in the form of photographs, film, or video signals, showing obvious advantages and long-term
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Fig 4 QuollC MKII with adjustable cross bar and camera adjustable heights
During the dry season in the Wet Tropics of north Queensland, it was found that lower overnight temperatures allowed moisture condensation being displaced from canopy leaves onto the ground. These wet conditions sometimes covered the perspex window with moisture and would render some of the recordings blurry. The sampled animals also showed some restricted imagery of the targeted genitalia and pouch, due to their relaxed posture while standing on the capturing window. Overcoming these situations quite significantly but not totally, a new “Quoll C MKII� weatherproof camera system was developed. Using a different collapsible apparatus in a U-shaped metal frame, [Fig 4] the apparatus was now sitting in a vertical position rather than the initial horizontal prototype, allowing, the lure to be easily raised and lowered accordingly to the species being targeted. A new design of the lure holdings, by adding a 45 degree elbow shape pipe fitting to the PVC bait holder also allowed a higher restricted access of the organic lure, removing the easy access to it by pigs, birds of prey and rats. A third camera could also be added to the system, to allow specific sections to be photographed or video recorded, of the animals. All
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Fig (a) Quoll C & QuollC MKII (b) prototypes, showing torso ( genitalia) imagery of a male and female quoll and sub-adult male quoll March 2018
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cost saving over animal traps. These advantages include being relatively non-invasive and cost saving of the necessity for fewer field workers and less work during the hours of darkness, with its associated occupational safety aspects. The initial outlay for cameras and the equipment can be considerable, but similar costs are often greater for trapping surveys, especially the person-hours in setting, checking and removing traps in the wild. Although there are still some challenging steps to overcome with camera settings best suited to detection and analysis for wildlife surveys and monitoring, there are clear benefits in the use of this new readily available technology. Acknowledgments My sincere thanks to my family especially my wife June and our closest friends for the support given during all my wildlife passion pursuit years. Dr. Tom Grant for his everlasting patience and continuous support on the revision and editorial comments, of my draft papers. References De Bondi N, White JG, Stevens M and Cooke R (2010). A comparison of the effectiveness of camera trapping and live trapping for sampling terrestrial small-mammal communities. Wildlife Research 37: 456465. Meek PD, Ballard G and Fleming P (2012). An Introduction to Camera Trapping for Wildlife Surveys in Australia. PestSmart Toolkit publication, Invasive Animals Cooperative Research Centre, Canberra, Australia. Vale, AN and Jackson, L. 2017. Interim Closure of Kauri Creek Road To Establish Road Usage Impacts During The Breeding Cycle of The Northern Spotted-tailed Quoll (Dasyurus maculatus gracilis), https:// issuu.com/albertovale1/docs/kauri_ck_rd_closure_report Quoll C Video by-catch capture example https://www.facebook.com/quolls/videos/526110287546117/ Š Alberto Vale 2018 This work is copyright. The Copyright Act 1968 permits fair dealing for study, research, information or educational purposes. Selected text, diagrams or images may be reproduced for such purposes provided acknowledgement of the source is included. Major extracts of the entire document are not be reproduced by any medium or process. This document should be cited as: Vale A. (2018) Non Invasive Pouch Monitoring Of The Spotted-tailed Quoll Dasyurus maculatus gracilis Using Camera Traps. Australian Quoll Conservancy publication under the auspices of WildCAM AustraliaŽ, Cairns, Australia.
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