A Supplemental HCVF Assessment on the Sumatran Tiger ...

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FINAL REPORT Tiger <strong>HCVF</strong> <strong>Supplemental</strong> <strong>Assessment</strong> – Serapung FMU 3.4.2 Remote Camera Methodology in this Study Adult tigers are known to habitually travel along specific routes, often well-worn animal trails, where they communicate with conspecifics by scent-marking (Sunquist 1981, Smith et al. 1987, Franklin 2002). Previous work has shown that this behavioural preference must be taken advantage of in the selection of remote camera sites if adequate photo-captures are to be achieved (Karanth & Nichols 1998, Franklin 2002). In this study the placement of remote cameras was based on identification of likely foci of localised tiger activity, as recorded during extensive preliminary field orientations, based on basic landscape analysis of habitat within and adjacent to the FMU, and in accordance with the need to distribute cameras as widely as possible across the target study area. Some camera sites were maintained throughout the assessment period, while others were moved and new sites chosen in response to changing field conditions and newly uncovered secondary evidence of tiger presence. With these constraints, commercially available TRAILMASTER® (Goodson and Associates, Lenexa, Kansas, USA) infrared-activated camera traps (TR-1500 model) were placed at a height of 40-50 cm, on trees and/or temporary mountings. The distance across the camera trap “gate”, between the infrared transmitter and receiver, ranged from 4 to 6 metres. The camera trap units and data loggers were concealed as much as possible, and the monitors programmed to take successive shots at a time interval of one minute, thus minimising unnecessary wastage of film whenever groups of animals (e.g. macaques) were present. Sensitivity of the infrared monitor was programmed on a site-specific basis, adjusting to ambient light levels during the brightest part of the day, thus maximising sensitivity and minimising false activation of the camera. All cameras were programmed to be operational for 24 hours per day, where battery life of cameras and monitors would provide up to 7 and 10 days constant operation under normal conditions. Camera systems were regularly checked, serviced, and films and batteries changed in-situ. The data logging features of the TR-1500 monitor, in combination with the “data-back” feature of the cameras, allowed reliable identification of the time and date of all photographs obtained by remote cameras during this assessment. It was the aim of this study to keep an average of 10 cameras operational during the field assessment period of 30 days. Maintenance and checking of cameras necessitated a minimum field period of 4 days, covering approximately 55-80 km on foot between camera sites. Time available between field trips was used to develop and catalogue photographs obtained, and to allow teams to focus on other data collection components described below. Camera positioning was optimized to photograph tigers and programmed to be active for 24 hours per day. On average films were collected and cameras serviced every 7 days. Some cameras were moved to new sites according to results achieved and in line with overall assessment goals. Due to theft, fire and ongoing security concerns related to the large number of illegal logging groups within the moratorium area a total of 150 active camera-trap days were achieved during the 4-week study period. 3.5 Rapid assessment field surveys Extensive ground-based surveys were a major component of the assessment methodology, requiring in excess of 150 person nights working from temporary forest camps set-up deep in the field. These surveys were carried out at two levels of intensity, serving different functions within the assessment methodology framework. Wide-ranging surveys, designed to maximize coverage of the study area, identifying Sumatran Tiger Conservation Program Pg 24/68
FINAL REPORT Tiger <strong>HCVF</strong> <strong>Supplemental</strong> <strong>Assessment</strong> – Serapung FMU and mapping evidence of tiger activity, high prey densities and specific vegetation and landscape features most likely to support tigers, accounted for 131 km of survey effort. An additional 106 km of survey transects were carried out under the more stringent and quantitative methodologies of a rapid assessment protocol developed by STCP to assess tiger distribution, prey abundance, habitat quality and levels of human disturbance. The routes of all surveys carried out during the assessment period were plotted by handheld GPS and later transferred to a geographical information system (GIS) map of the FMU and surrounding landscape. In order to assess distribution of survey effort across the study site an ArcGIS 8.1 (ESRI) GIS density function was utilised based on division of the study site into 1 km 2 survey blocks. Total survey distance covered in each of these 1 km 2 blocks was calculated to provide an index of survey intensity across the study site. This index of effort is graphically displayed below both for all surveys (Figure 6) and for rapid assessment surveys only (Figure 7). Samples of tiger faeces were collected whenever encountered by survey teams. The samples were later desiccated in order to facilitate the examination and characterisation of hairs, bone fragments and other indigestible remnants indicative of specific prey species. Sumatran Tiger Conservation Program Pg 25/68
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