Identifying the variation in utilization density estimators and home ranges of elephant clans in Aceh, Sumatra, Indonesia

Abstract

Movement ecology is fundamental to understanding animal home ranges or utilization distribution (UD), and is an important aspect in conservation management strategies. Over the years, there have been several new developments and some contention on which methods are best in determining animal movement and UD. Using data from Global Positioning System (GPS)-tracked Sumatran elephants, minimum convex polygon values (MCP), various Kernel Density Estimator bandwidths (KDE), and dynamic Brownian Bridge Movement Models (dBBMM) were compared to identify the most suitable estimators of space-use. Models were analyzed for variability of home range, goodness of fit, isopleth contour complexity, and precision in representing habitat features. dBBMM was shown to be the most efficient in their representation of elephant home range estimations when compared to other methods in terms of trade-off between type I and type II errors and their ability to classify high- and low-use areas, along with insight into variation of movement. We further discuss the implications of variability in home range estimation regarding conservation and provide recommendations for future studies using similar data.