Tahlequah, the Orca Whale Who Once Grieved Her Dead Calf for 17 Days, Is a Mother Again

The orca whale who broke hearts in 2018 while grieving her dead calf for 17 days has a welcomed a new calf.

Tahlequah, also known as J-35, gave birth to her new addition on Friday, Sept. 4, according to the Center for Whale Research, which added that the baby whale "appeared healthy and precocious, swimming vigorously alongside its mother in its second day of free-swimming life."

Researchers noted that, based on the approximate 18-month gestation period, Tahlequah became pregnant back in February 2019. The team identified that the whale was expecting again back in July.

"Tahlequah was mostly separate from the other whales and being very evasive as she crossed the border into Canada, so we ended our encounter with her after a few minutes and wished them well on their way," researchers said.

The mother whale made worldwide headlines back in summer 2018 when she embarked on her so-called "Tour of Grief," swimming with her calf who died 30 minutes after birth. Tahlequah traveled some 1,000 miles with her pod while towing the late newborn.

"We hope this calf is a success story," said researchers. "Regrettably, with the whales having so much nutritional stress in recent years, a large percentage of pregnancies fail, and there is about a 40 percent mortality for young calves."

RELATED: Zoo Berlin's Twin Pandas Pit and Paule Turn 1: They 'Have Grown Very Dear to Us'

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories

Tahlequah is part of the Southern Resident whales that live in the Puget Sound in the Pacific Northwest region of the United States, a group of orcas that were listed as endangered in 2005. The orcas make up three different pods, which researchers have dubbed J, K and L.

John Durban and Holly Fearnbach, scientists with the Southall Environmental Associates and SR3, respectively, discovered that Tahlequah was pregnant using drone imaging, the Seattle Times reported in July.

An image of Tahlequah from that month compared to one in September of last year showed her middle notably enlarged.

RELATED VIDEO: Penguin at Perth Zoo Loves to Watch Videos of Other Penguins

RELATED: Chicago Zoo Welcomes Adorable Endangered Zebra Foal: 'It's Hard Not to Smile'

The whale's second pregnancy, however, was not guaranteed — about a third of the pregnancies among the Southern Residents don't make it, according to a study out of the University of Washington.

"Lack of prey, increased toxins and vessel disturbance have been listed as potential causes of the whale’s decline," the study, published in 2017, said. The orca's main food source is Chinook salmon, which are also endangered.

According to the National Wildlife Federation, climate change and pollution are also large threats to the marine animals. Last May, another whale gave birth among the Southern Residents population, which the Center for Whale Research called a "very welcome addition" due to the struggling population.