A newborn orca calf has been spotted with a family of southern resident killer whales, bringing a welcome boost to the endangered population. 

Photographed with the group known as J Pod on Friday (Dec. 20), the calf is thought to be only a few days old.

Orca Conservancy, a U.S.-based organization working to help recover the critically endangered southern resident killer whale population, has confirmed to Black Press Media it is a new southern resident calf.

Tamara Kelley, director of development, said the calf was seen travelling with a female orca, identified as J35 Tahlequah, which 鈥渟uggests she may be the probable mother.鈥�

"Researchers will confirm the maternity after three or more encounters with the calf," she added.

Further observations of the calf will also help researchers age the calf, as well as assess its health.

"It is difficult to tell the health of newborn orcas as they appear to be lumpy and bumpy when first born, but over the next few weeks the calf should begin to fill out, and that is when researchers will have a clearer idea of the health status," said Kelley.

The calf was photographed on Dec. 20 by Brittany Philbin from the Washington State Ferry vessel, just south of Edmonds, Washington State.

"This was definitely a welcome and unexpected surprise today when I went out looking for the whales," she said.

News of the calf brings some hope to the future of the southern residents, who have seen numbers drop to their lowest point since 2020

It was reported in November the southern resident killer whale population had dropped to 72 after an adult male orca and a calf were both listed as missing, presumed dead.

Kelley says Orca Conservancy is "cautiously optimistic" about the news.

"The calf mortality rate of southern resident killer whales is 50 per cent, and the last two calves that have been born into this population (J60 and L128) have sadly not survived," she says.

"It will be interesting to see if J35 is confirmed to be the mother as she has had two successful calves (J47 and J57). And she is also famous for carrying her deceased calf around for 17 days in 2018."