The well known elephant rescue, David Sheldrick Trust, runs a sanctuary in the park that hand-rears orphaned elephant and rhinoceros calves, and later releases them back into secure sanctuaries. Orphaned and sick animals are brought to the sanctuary from all over Kenya. Nairobi National Park has also acquired the nickname ‘Kifaru Ark’,a testament to its success as a rhinoceros (kifaru in Kiswahili) sanctuary. The park is now home one of the world’s densest concentration of black rhinoceros with over 50 individual animals.