Dry season diets and habitat use of sympatric Asian elephants (Elephas maximus) and greater one‐horned rhinoceros (Rhinocerus unicornis) in Nepal

Abstract

Dry season diets and habitat use of increasing populations of Asian elephants Elephas maximus and greater onehorned rhinoceros Rhinoceros unicornis in the Babai Valley of Royal Bardia National Park, Nepal, are described, and an assessment is made of the potential for competition between them. The diets, analysed by microhistology, were different, with a similarity index of 37.5%, and with different grass/browse proportions: the rhino diet consisted of 63% grass and 28% browse; that of elephants was 24% grass and 65% browse. A tallgrass floodplain grass, Saccharum spontaneum, was the plant most eaten by rhinos, whereas elephants consumed a large proportion of bark of Bombax ceiba and Acacia catechu, as well as several browse species not eaten by rhino. The habitat use of elephants was determined by dung-counts within 30 km of 20-m wide belt transects, while that of rhino was taken from an earlier study. Elephants used a wider range of habitats than rhino, but two types, the tallgrass floodplain and khair-sissoo forest, were preferred by both species simultaneously. While elephants used the abundant sal forest extensively, rhino strongly avoided this habitat. Densities of both species were low at the time of study (< 0.5 animals/km 2 ), but their numbers are expected to increase markedly in coming years. Because available habitats for expansion are limited, this may lead to competition. Rhino might then become the weaker species, as elephants are more flexible in their ranging and foraging activities. The tallgrass floodplain habitat and its important forage grass S. spontaneum may then become the critical resources.

Ranging behavior of the Asian elephant in Sri Lanka

“…Thus, intra-and inter-sexual range overlap was extensive, suggesting neither male nor female elephants defend territories. Elephants ingest substantial amounts of low quality food, feeding for about 17 hours a day (Sukumar 1989a) on a wide range of plants (Mueller-Dombois 1972;Ishwaran 1983;Steinheim et al 2005) to meet their nutritional requirement. Therefore, for Asian elephants, food represents a limiting resource that is dispersed, the exploitation of which necessitates a major investment in time and locomotion.…”

Dry season diets of sympatric ungulates in lowland Nepal: competition and facilitation in alluvial tall grasslands

“…Some researchers have pointed out the necessity of applying correction factors to accurately estimate diets by this method (Dearden et al 1975;Westoby et al 1976;Vavra and Holecheck 1980); however, Alipayo et al (1992) advocated the accuracy of the technique. In Asia, this method has successfully been applied to diet studies of rhino (Jnawali 1995), swamp deer (Pokharel 1996), takin Budorcas taxicolor (Wangchuk 1999), Asian elephant (Steinheim et al 2005) and mountain ungulates (Harris and Miller 1995;Shrestha et al 2005).…”

“…However, few studies have compared the diets of wild sympatric herbivores in the Asian subtropics (Dinerstein 1980;Martin 1982;Johnsingh and Sankar 1991;Bagchi et al 2003;Steinheim et al 2005). As a step in unravelling the complex interactions among sympatric ungulates in this region, in this study we describe the diets of rhino, swamp deer and hog deer at broader (forage category) and finer scale (within each forage category), and based on the results we discuss the potential for forage competition and facilitation between them.…”

Effects of Human Activities on Home Range Size and Habitat use of the Tsushima leopard Cat Prionailurus bengalensis euptilurus in a Suburban Area on the Tsushima Islands, Japan

“…If a significant difference was recognized between expected and observed utilization frequencies, we calculated Bonferroni confidence intervals to determine which habitat types were preferred or avoided (Byers et al 1984, Kiyota et al 2005. To estimate the magnitude of the habitat preference, we calculated the Ivlev's electivity index (Ivlev 1961;Steinheim 2005).…”