When he was born on April 20, Dafari weighed about 30 kilograms.

The solid little man weighed in at 125 kilograms last week and keeper Scott Smith said he expected Dafari to gain on average a kilogram a day for the next few weeks.

"He's definitely enjoying his food at the moment."

Mr Smith said when Dafari was fully grown in a few years time, he would weigh more than 1200 kilograms.

Dafari was growing at such a rapid rate, Mr Smith said keepers were forced to increase mother, Bakhita's intake to keep up with the hungry calf.

While he has began to explore solid foods, Mr Smith said the keepers "expected he will continue to drink his mother's milk for quite some time."

Described as a "confident calf" by Mr Smith, he said Dafari and Bakhita were settling in well to their new surroundings in the public enclosure.

The third calf to be horn into the Zoo's internationally renowned breeding program, Taronga Western Plains Zoo general manager, Matthew Fuller, said Dafari's involvement in the future could be very beneficial.

With only about 4000 black rhinos surviving in the wild, Mr Fuller said the number of births over the next six years would be watched closely. "Only time will tell if he remains in Dubbo or is transferred when he reaches breeding maturity," he said.