As the rhinoceros population is constantly decreasing, efforts are being made to stop the poaching of the rhinos.
The rhinoceros population at Manas is estimated to be 100, and more than 1,000 elephants are believed to live in the area.
The rhinoceros population has been similarly decimated, with wildlife experts estimating that about 10,000 survive in the wild.
Kenya has gingerly started to build back its black rhinoceros population.
The long term goal of the sanctuary is to "build a sustainable rhinoceros population and relocate rhinos back to their original habitat in Uganda's protected areas".
It is also possible that several species of Gyrostigma are extinct because rhinoceros populations are tiny owing to their state of endangerment.
Despite an official ban on trading in the horns, the rhinoceros population in Africa has dropped to 3,800, from 60,000 in 1970.
Nepal's rhinoceros population has risen significantly over the past three years thanks to better security against poachers and community conservation programs.
Demand for these exploded in the 1970s causing the black rhinoceros population to decline 96% between 1970 and 1992.
Most Indian rhinoceros populations in zoos are related to the one in Basel.