Mirage Casino Forced to Temporarily Close Dolphin Habitat After Third Animal Dies This Year

Getty Stock photo of a dolphin not the late K2

An 11-year-old dolphin has died at The Mirage's Secret Garden and Dolphin Habitat in Las Vegas, causing the exhibit to temporarily close its doors.

A memo sent to employees from Mirage Interim President Franz Kallao and shared with PEOPLE on Monday says that K2, a bottlenose dolphin, had been suffering a respiratory illness for which he was undergoing treatment. He died on Saturday.

"All of us are heartbroken over this tragic loss, especially our amazing animal health and care teams who love and care for our animals on a daily basis," wrote Kallao, noting that much of the staff had seen K2's birth and "watched him grow" into an adult.

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Kallao said, "K2 was very vocal, energetic, loved his toys and was a joy to be around. He always made us smile."

His cause of death hasn't been determined, however, the exhibit is working with veterinarians and pathologists. They will also be looking into the well-being of animals that are still at the exhibit as well as the venue itself, Kallao said.

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"I cannot stress enough that nothing is more important to us than the health, safety and welfare of the animals entrusted in our care," added Kallao. "We are temporarily closing the Secret Garden and Dolphin Habitat to focus our efforts on ensuring that we have the safest possible environment and the best care possible for our dolphins and to give our team the time they need to process and grieve."

He concluded, "There are no words that can adequately describe the pain that all of us feel. Please join me in wishing our sincerest condolences to our Mirage teammates over this tragic loss."

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According to the exhibit's website, it is closed until Oct. 9.

K2 is the third dolphin who has died at the habitat this year.

The first was Maverick, 19, who died earlier this month and Bella 13, who died in April, according to multiple outlets.

Both dolphins were being treated for illnesses in the weeks preceding their deaths, according to FOX 5 Las Vegas.