Bob McPherson, who has been taking whale photos for about 27 years, said the newborn calf was spotted in Portland waters alongside its mother on Wednesday morning.

"It's got to be a new one, it only sprung up this morning," he said.

"It must have been born in the last three or four days at a guess. It's pretty unique as it seems early in the season for a calf to be born."

Mr McPherson said people had been "waiting for some of them to turn up".

"They started off near the main lighthouse in Portland and were travelling up and down east of Lee Breakwater throughout the day," he said.

"There's quite a few people here taking photos and videos, having a good look as it's pretty close."

Mr McPherson said the calf appeared to be "small and young".

"It's just amazing and is, I guess, a sign of what we have all been looking for," he said.

Almost every year between June and September, female southern rights return to south-west waters to calve.

The whales often swim within a hundred metres of the shore.

In summer, southern right whales live in the sub-Antarctic. In winter, they migrate to warmer waters around the southern areas of Australia.

The females migrate to the 'nursery' areas close to the shore to bear their calves, while the males, yearlings and young adults remain further out to sea.