Orca who carried her dead newborn 1,000 miles gives birth to another new calf

The killer whale who captured hearts across the world in 2018 for refusing to let go of her dead calf has given birth to her second baby in the last four years.

The Center for Whale Research said a team of researchers was able to begin observation of the newborn girl Monday, giving the calf the alphanumeric designation J61. The center added that it was "eager" to conduct follow-up observations of the calf.

Her mother is known as Tahlequah, designation number J35. Researchers assign the animals alphanumeric identifications and eventually nicknames to go with them.

The Center for Whale Research expressed concern for the health of both J61 and her mother.

"Early life is always dangerous for new calves, with a very high mortality rate in the first year," the Center for Whale Research said Tuesday. "J35 is an experienced mother, and we hope that she is able to keep J61 alive through these difficult early days."

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Tahlequah made international headlines in 2018 when she carried her dead newborn calf for 17 days, tugging on the heartstrings of humans everywhere. By the time she let the baby's carcass go, she had carried the calf across 1,000 miles on her head.

Washington Gov. Jay Inslee had already signed an executive order that year establishing the Southern Resident Killer Whale Task Force. The goal was to study ways to preserve and restore the local orca population.

J61 is Tahlequah’s third baby calf to survive. Her oldest, J47, or “Notch,” was born in 2010, and her second, J57, or “Phoenix,” was born in 2020.

Tahlequah and her children live within the J-pod of orcas, inhabiting waters along the coast between Washington state and Vancouver Island, British Columbia.

The J-pod is one of three pods of killer whales known as the “Southern Resident” orcas. There are only about 73 orcas across all three pods, according to the Orca Conservancy.

According to NBC affiliate KING of Seattle, a study this year showed that the Southern Resident pod is declining by about one whale per year and that fewer than two dozen will be left within this century.

Orcas are considered an endangered population as they face a variety of threats, including entanglement in fishing nets, dwindling food supply, human interference and pollution of their environments. It’s estimated there are only 50,000 killer whales globally.

Contaminants in the water are a large concern for the killer whale population. Toxins from industrial chemicals don’t break down, and they become concentrated in the food chain supply and are then stored in the orcas' fat, according to the Georgia Strait Alliance.

Baby orcas are exposed to contaminants through their mothers' milk, which threatens their survival in their first year, the alliance said.

The National Oceanic and Atmospheric Administration noted that there are "relatively high contaminant levels" among the female Southern Resident whales and their offspring.

"We are concerned about the impact these contaminants might be playing in this population," NOAA said in its 2022 health assessment of the pod. 

This story originally appeared on NBCNews.com. Read more from NBC News:

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