A female beluga whale, Kharabali, passed away Wednesday at the Mystic Aquarium in Connecticut after being in intensive care for almost 11 days.

Kharabali, who arrived at the aquarium from Canada's Marineland in May 2021, was around 9 and a half years old, a spokesperson of the aquarium, told USA TODAY. Beluga whales can live up to 90 years, according to the National Oceanic and Atmospheric Administration.

"This loss weighs heavily on us, especially our animal care staff," said Mystic Aquarium in a statement on social media. "It is defeating and disheartening as the team works fiercely and with immense compassion to ensure these whales receive world-class care in sickness and health."

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How did Kharabali die?

Kharabali began to exhibit abnormal swimming in November, said the aquarium, prompting their husbandry team and veterinarians to examine the animal. As the aquarium staff tried to understand what was wrong with her health, Kharabali's strange behavior continued to progress, said the aquarium, so they moved her to the holding pool and eventually to the intensive care facility at the Aquatic Animal Study Center at Mystic Aquarium, where she remained for 11 days before she passed.

Mystic Aquarium said that the facility's veterinary and animal care teams "spared no effort" in trying to save the whale, providing her with round-the-clock medical treatment and monitoring. A spokesperson told USA TODAY that the aquarium's staff spent hours in 20 degrees water, holding the whale to help her sustain her blowhole over the water.

"Despite intensive care for multiple health issues and all life-saving efforts, she passed away in the company of the dedicated Mystic Aquarium team that had been by her side throughout," said the aquarium in their statement.

Kharabali's exact cause of her death will be known after a necropsy is conducted, said the aquarium.

Chief Zoological Officer at Mystic Aquarium Dr. Allison Tuttle said that Kharabali's "spirit touched us all" and that they are "heartbroken by her passing".

Third whale to pass

The aquarium said that Kharabali was the third whale from Marineland to pass away after arriving at Mystic Aquarium. Earlier, Havok passed in August 2021 while Havana passed in February 2022.

"Both were found to have underlying incurable conditions which led to their deaths that were unable to be diagnosed while alive," said the aquarium.

A fourth juvenile beluga from Marineland, Jetta, began receiving around-the-clock treatment in the fall of 2021 for almost a year before she could be returned to the main habitat.

Fortunately, the whale is now out of critical care and is thriving.

"Jetta is our like beacon of light in this whole thing," said the spokesperson.

Animal rights activists had tried to block the whales' move from Canada to the U.S. but had not been successful in their mission, as per the Associated Press. They alleged that the permit granted by the U.S. Commerce secretary and National Marine Fisheries Service didn’t adequately address the potential harm to the belugas caused by being moved to the Connecticut aquarium.

However, the spokesperson told USA TODAY that the whales had had "normal physiological responses" to the transport and acclimatized quickly to their new surroundings.

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In a statement, Marineland thanked Mystic Aquarium for providing "exceptional care" for the beluga whales and adopting them in midst of COVID.

"Marineland is deeply thankful for Mystic Aquarium's professionalism and tireless efforts in safeguarding the health and happiness of these beloved marine creatures," said the statement.

Allegations of animal cruelty

Meanwhile, a beluga whale also passed at Marineland in Canada just two days after Kharabali's death, reported the Toronto Star, bringing the total number of whales that have died at the Niagara Falls tourist attraction to 15 over the past four years.

Ontario's Animal Welfare Services has been investigating Marineland since it took over animal cruelty enforcement in 2020, said the Star.

In May 2021, the same week Kharabali and her friends were moved to Connecticut, Ontario's Animal Welfare Services found all marine mammals at Marineland to be in distress due to poor water quality, as per the Star. However, Marineland denied the allegations and has maintained on its website that it has a "strong record" of providing for the welfare of its animals.

'Canary of the sea'

Known as the "canary of the sea," for their white color and range of vocal sounds, beluga whales are protected under the Marine Mammal Protection Act, as per NOAA. They weigh an average of 3,150 pounds and can grow up to 16 feet in length.

They are very social animals, forming groups to hunt, migrate, and interact with each other. Beluga whales are throughout the Arctic and sub-Arctic waters and are mostly found in Alaska in the United States, says NOAA.

Mystic Aquarium is accepting condolence messages from their well-wishers and those who knew Kharabali. Anyone wishing to share condolences or offer support can contact the aquarium at [email protected]. Any questions may also be directed to the same email address.

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Saman Shafiq is a trending news reporter for USA TODAY. Reach her at [email protected] and follow her on X, the platform formerly known as Twitter @saman_shafiq7.