A dolphin, named Kai, from Dolphin Quest’s Hawaii island location, died Thursday at Dolphinaris Arizona. Now, Dolphin Quest is terminating their contract with the dolphin attraction.

Kai was transferred on loan from Dolphin Quest’s Hawaii island facility to Dolphinaris Arizona in September 2016. The 22-year-old male dolphin showed signs of his health declining for about two weeks before Dolphinaris Arizona staff members decided to “humanely euthanize” him, according to a recent post on their website.

“His condition deteriorated following signs of difficulty swimming, eating and breathing,” Dolphinaris Arizona officials said on their website.

Kai is the fourth dolphin death within two years at Dolphinaris Arizona. After being “heartbroken” over the most recent death, Dolphin Quest officials decided to terminate their animal loan contract with the Phoenix-area aquatic facility, according to a press release.

“The safety and health of our animals is our top priority”, says Dr. Rae Stone, co-founder of Dolphin Quest in a press release. “In spite of their best efforts, the animal health concerns have not been resolved at Dolphinaris. We have a senior marine mammal specialist from Dolphin Quest on site at Dolphinaris who knows our remaining dolphins well and is closely monitoring them. They are bright, alert and in good condition at this time. We have contacted USDA and are working with them as we move forward.”

Dolphin Quest, which has two locations in Hawaii and one in Bermuda, has two remaining animals at Dolphinaris Arizona and they are currently deciding on the next steps for them.

“We recognize losing four dolphins over the last year and a half is abnormal,” said Christian Schaeffer, a general manager at Dolphinaris Arizona. “Over the last several years we have worked with a team of external experts in the fields of animal behavior, water quality and veterinary care to ensure our dolphin family remains healthy. We will be taking proactive measures to increase our collaborative efforts to further ensure our dolphins’ wellbeing and high quality of life.”

Kai participated in educational and experiential learning programs.

Over 100 protesters rallied outside Dolphinaris Arizona today, calling for its closure.

The Associated Press contributed to this story.