Jack Hanna, Former Columbus Zoo Director, Has Dementia and Is Retiring From Public Life

The zookeeper's dementia has progressed into Alzheimer's disease, his family believes.

Jack Hanna, the beloved former director of the Columbus Zoo and Aquarium, has been diagnosed with dementia which his family believes has now progressed to Alzheimer's disease, his three daughters announced on Wednesday.

In a statement posted on Hanna's Twitter account, his daughters -- Kathaleen, Suzanne and Julie -- shared that his condition had progressed much faster in the last few months than any of his family could have anticipated and he is now no longer able to participate in public life as he used to. Hanna, 74, became director of the Columbus Zoo in 1978 and is known for his popular weekly TV programs -- which included Animal Adventures, Into the Wild and Wild Countdown -- and has also made countless television appearances. Although he left his active management role as Executive Director of Columbus Zoo in 1992, he continued to be a spokesperson for the zoo until his retirement last year.

"A passion for wildlife conservation and education has been at the core of who our dad is and everything he has accomplished with the help of so many," the statement reads. "He spent his life connecting people and wildlife because he has always believed that having people see and experience animals is key to engaging them in more impactful conservation efforts. ... Even though Dad is no longer able to travel and work in the same way, we know that his infectious enthusiasm has touched many hearts and will continue to be his legacy."

"While Dad's health has deteriorated quickly, we can assure you that his great sense of humor continues to shine through," the statement continues. "And yes -- he still wears his khakis at home."

Hanna's children noted that his wife, Suzi, continues to remain at his side.

"She continues to be his rock (and ours, too)," the statement reads. "We have great respect and admiration for Mom as we move through...this difficult time with Dad."

Ohio Gov. Mike DeWine also tweeted a statement in support of Hanna and his family during this difficult time.