A zoo in Canada has received a Christmas gift of a baby white rhino, the first such birth at the zoo since 1990.

The Toronto Zoo, in Toronto, Ontario, announced the happy event in a Facebook post on Thursday (Dec 28).

"We're excited to announce that on Christmas Eve, our white rhino Zohari gave birth to a male calf at 10.45pm," it said.

Both mother and calf are doing "very well", even though the first-time mother is said to be "very tired".

"The calf is very big and strong, weighing in at 62.3kg, he has been eating more than would be expected, and he apparently has very hairy ears," the zoo added.

A video of the pair posted on Facebook shows the tiny tot sticking close to its mother.

The birth was the fifth white rhino birth in Toronto Zoo, and the last one was born in 1990.

The calf, whose name has not been released, was born to seven-year-old Zohari and a 10-year-old male rhino named Tom, Toronto's The Star news site reported on Thursday.

The Toronto Zoo is part of the White Rhinoceros Species Survival Plan, which aims to establish and maintain healthy and genetically diverse populations.

White rhinos, the second-largest land mammals after elephants, are a conservation success story.

They were rescued from the brink of extinction - with just a mere 20 white rhinos left in the wild at one point at a reserve in South Africa - and now have a status of "near threatened", according to the World Wide Fund For Nature (WWF).

There are an estimated 20,000 of the animals in the wild.

Black rhinos, on the other hand, are critically endangered with just over 5,000 left in the wild.

The Toronto Zoo called the birth of its calf "very important" for white rhinoceros conservation as the species is currently listed as near threatened on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species.