Mystic — Less than three weeks after a male beluga whale it imported from Marineland Canada died, Mystic Aquarium announced Tuesday night that another one of the five whales brought to its facility in May is "extremely ill and failing." 

In a Facebook post, the aquarium reported that the female beluga "has been receiving constant, individualized attention and medical support from our best experts on a 24/7 basis" since joining the Arctic Coast exhibit.

The post stated that in recent weeks, tests have revealed the whale was suffering from "several concerning health complications, including a low white blood cell count and gastrointestinal issues." It stated the aquarium's veterinarian team is monitoring the beluga around the clock, exploring every treatment option and has contacted beluga experts across the country who are traveling to Mystic to help.

The aquarium pointed out that there was "widespread agreement among all parties concerned about beluga whales, including many animal rights groups and Marineland," that some of the Marineland belugas, who were born in captivity, needed to be moved out of that facility.

Media reports have stated Marineland has been the subject of complaints and investigations, including about overcrowding, and numerous orcas have died there.  

"Mystic Aquarium is the best possible location for these animals: a world-class facility with decades of marine mammal experience and a top-level understanding of beluga health and husbandry where they have the opportunity to contribute to research that can save endangered populations. The veterinarians at our facility are dedicating the entirety of their time and energy to return this beluga to full health," the aquarium stated Tuesday night.

The aquarium said it would provide updates on the beluga's condition as they become available.

On Aug. 6, the aquarium announced that a 6-year-old male, who arrived with four female belugas from Marineland, had died. He was being treated for gastric ulcers developed before arriving and had been showing signs of improvement throughout his acclimation period, according to the aquarium. A necropsy was done to determine the cause of death.

While the aquarium's post on Tuesday said the ill female whale had been receiving attention since arriving in Mystic, when the male whale died, an aquarium spokesman said the four other beluga whales "were healthy and behaving normally."

The aquarium had moved the five whales to its Arctic Coast habitat to join its three resident belugas: Juno, an 18-year-old male; Natasha, a 41-year-old female; and Kela, a 40-year-old female. The aquarium said the whales would aid the research it does to help protect whales in the wild.

The decision to transport the whales to Mystic from Canada was a controversial one, with some animal rights groups opposing the move. Marine animal advocates argued the transport would endanger the whales and violated the intent of a 2019 Canadian law aimed at phasing out the captivity of whales, dolphins and other cetaceans. The law is designed to eventually end the captivity of cetaceans in Canada by banning their breeding. The import permit from the U.S. National Marine Fisheries Service prohibits the animals from being bred for at least five years or included in public performances.

j.wojtas@theday.com