Andean bear home ranges in the Intag region, Ecuador

Abstract

I estimated home ranges of 5 female and 4 male Andean bears (Tremarctos ornatus) inhabiting the Intag region in Ecuador between September 2001 and December 2006, using 1,439 and 412 telemetry locations for females and males, respectively. Multi-annual and seasonal home ranges were estimated using 2 methods: minimum convex polygon (MCP) and nearest-neighbor convex hull (k-NNCH) analyses. I considered k-NNCH analysis the best method for estimating Andean bear home ranges in fragmented landscapes such as those across the study site. Annual home range of males (59 km2) were larger than those for females (15 km2) using the k-NNCH method. During the rainy season home ranges of males were 23 km2 versus 10 km2 for females, and in the dry season, 27 km2 versus 7 km2. All bears in this study showed some degree of home range overlap, indicating intra-specific tolerance. The mean annual k-NNCH home range of males overlapped home ranges of females by 32%, and among females, overlap was 22%. No evidence of territorial behavior was observed in this study.