The mineral content of food plants of the Sumatran rhinoceros (Dicerorhinus sumatrensis) in Danum Valley, Sabah, Malaysia

Salt licks are known to be an important source of minerals for herbivores. For the two-horned Asiatic or Sumatran rhinoceros, Dicerorhinus sumatrensis, the role of salt licks in its mineral nutrition is still unclear. Studies in Indonesia have indicated that D. sumatrensis supplements its mineral requirements by using salt licks. In contrast, D. sumatrensis was also observed to live in the Endau Rompin forest of Peninsular Malaysia where salt licks are not known to exist. In Sabah salt licks are present in several locations and believed to affect rhino distribution. There is very little information on mineral nutrition of the Sumatran rhinoceros in Danum Valley, Sabah (ca 5 degree 00'N, 117 degree 30'E). Works by Mokhtar et al. have ruled out wallow soil as a possible mineral source for the Danum rhinos. Although several mineral licks were discovered in the area as recently as September 1992, there is still no evidence of use of these licks by rhinos. To provide more information on the mineral nutrition of the Danum Valley Sumatran rhinos, we have carried out a survey on the mineral content of the rhino food plants.