Dry-season habitat occupancy by ungulate tiger prey in the Hukaung Valley of northern Myanmar

Abstract

We assessed habitat occupancy and distribution of principal tiger (Panthera tigris) ungulate prey species to assess factors affecting their occurrence and their potential contribution to low tiger presence in the core part of the Hukaung Valley Wildlife Sanctuary, in northern Myanmar. We surveyed for signs on 1,651 km of transects partitioned into 554 sampling units between November 2007 and May 2008. By incorporating seven environmental and four social covariates, we predicted habitat occupancy rates of 0.76 for gaur (Bos gaurus), 0.91 for sambar (Rusa unicolor), 0.57 for wild pigs (Sus scrofa), and 0.89 for northern red muntjac (Muntiacus vaginalis). Overall, shorter Euclidean distances to ranger stations and trails, decreased stream density, and broadleaved evergreen/semi-deciduous forest and relatively rare rain-fed cropland habitat occurrence positively influenced prey habitat occupancy; conversely, shorter Euclidean distances to villages, roads, and streams, higher elevations, and occurrence of mixed broadleaved and needle-leaved forest habitat negatively influenced occupancy. In addition, Euclidean distance to ranger stations, trails, and roads positively affected species detections, whereas shorter Euclidean distance to villages and streams, high elevations, and high precipitation negatively affected detections. Results indicated that all four prey species were relatively well-distributed through the Sanctuary core area, but comparisons with indices of abundance elsewhere suggest that prey density was low and would not likely support many tigers.