Elephant camera trap detection events, Ruaha-Rungwa 2018-2019

Abstract

This dataset was generated by a study investigating how anthropogenic risk affects the active periods of African savanna elephants. This dataset includes the date, time, and location of independent detection events of elephants from camera trap photos obtained during the deployment of four camera grids in the Ruaha-Rungwa ecosystem of Tanzania in the dry seasons of 2018 and 2019: Grid 1 (RNP) in core area of Ruaha National Park, Grid 2 (MIO) in a miombo wilderness zone of Ruaha National Park, Grid 3 (MBO) in MBOMIPA Wildlife Management Area, Grid 4 (RUI) in the Rungwa-Ikiri block of Rungwa Game Reserve. Grid 1 was considered a low-risk area for elephants. Grids 2, 3, and 4 were considered high-risk areas for elephants. We defined independent elephant detection events as images of elephants that were separated by more than 15 minutes. We noted the start time (the time of the first photograph in an event) and the midpoint for each event. Event times in the dataset are expressed in 'sun time', in order to account for geographic and temporal variation in the times of sunrise and sunset over the study area and study period. We used the SunTime function in the overlap package (Ridout & Linkie, 2009) in R to convert clock times (time on a 24-hour clock) to sun times (Nouvellet et al., 2012). We also coded group type for each detection event as: cow-calf (CC), lone bull (LB), bull group (BG), mixed group (M) of cow-calf plus mature males, or unknown (U). Each row in the dataset is a detection event. References Nouvellet, P., Rasmussen, G. S. A., Macdonald, D. W., & Courchamp, F. (2012). Noisy clocks and silent sunrises: measurement methods of daily activity pattern. Journal of Zoology, 286(3), 179-184. Ridout, M. S., & Linkie, M. (2009). Estimating overlap of daily activity patterns from camera trap data. Journal of Agricultural, Biological, and Environmental Statistics, 14(3), 322–337.