Applying a high-precision tracking system to distinguish the spatiotemporal patterns of animal movement in grassland ecology

Abstract

Spatial heterogeneity in vegetation may derive from variation in animal movement patterns, but these patterns have been difficult to study at the fine spatial and temporal resolutions necessary to relate them to small-scale vegetation patterns. Here, we demonstrated the utility of Ultra-WideBand (UWB) technology to examine animal movement patterns. We evaluated UWB performance in a field setting and illustrated how these data could distinguish movement patterns of different types of livestock during day and night. The data were of high spatial resolution (within 9.7 cm ± 1.7 cm of actual locations) and high temporal resolution (every second). The positional data clearly demonstrated differential movement patterns between a cow and ewe and between daytime and nighttime. Furthermore, patterns were spatially heterogeneous: the cow spent up to 5% of the day in a single 1 m2 square and the ewe up to 7.6% of the day in a single square. Over the course of one day, the cow visited about two-thirds of the plot whereas the ewe visited about half of the plot. Our study suggests that UWB technology is a practical tool to describe animal movement at fine spatial and temporal scales. We note some limitations of this technology (battery life, receiver range, and cost) and end by identifying some opportunities for it to improve ecology and conservation, particularly when combined with other data or technologies such as high-resolution vegetation mapping.