Thesis (M.Sc.)--York University, 2003. Graduate Programme in Biology. / Typescript. Includes bibliographical references (leaves 114-120). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ86299

While we should celebrate the bicentennial of naming the Sumatran rhinoceros (SR), the only extant population on earth might be on the island of Sumatra. Since Strien's 1986 study in Mamas Valley, Leuser, very little more has been learned about how this species distributed and what factors are influencing its extirpation. This study is the first conducted in Sumatra at an Island-wide scale. Using hierarchical models, I estimate the occurrence rates (%) and indices of abundance of SR on three remaining population areas: Leuser Landscape (LL) in 2007 (2.77%, 26 (CI 12-61)), Way Kambas (WK) in 2008 (33.58%, 27 (CI 14-50)) and Bukit Barisan Selatan (BBS) in 2010 (36.4%, 31 (CI 19-66)). Primary dry land forest and rivers are factors affecting SR occurrence in LL, but the index of abundance also is affected by deforestation, roughness of terrain, and and a vegetation index. The index of abundance in WK is more affected by major roads, and brush and savannah cover types, and the occurrence there is additionally affected by deforestation. Secondary dry land forest, regular roads, and deforestation is affecting both the occurrence rate and index of abundance of SR in BBS. The identification of these environmental and disturbance factors is translated into spatially explicit map that can be used to update the IUCN distribution map. In LL, by comparison to the historical distribution based on Strien (1986), the small population in Bendahara Mountain might still persist outside the core population in Mamas Valley.