Lincoln Park Zoo gorilla, Bana, dies at 29

Bana, a female western lowland gorilla who lived at Lincoln Park Zoo, died Tuesday.

She died after zoo officials made the decision to euthanize the 29-year-old ape after diagnoses of congestive cardiac failure and pneumonia earlier this month.

Zoo officials were tipped off something was wrong after Bana stopped eating as much as she regularly did and appeared lethargic, zoo spokeswoman Anna Cieslik said.

In a statement issued Thursday, zoo officials said: “Animal care and veterinary staff worked diligently to ensure she was taking her medications in an effort to improve her heart’s function. Unfortunately, full recovery in this condition is not possible, and in this case, even stabilization was not successful. After an abrupt decline on March 26, veterinarians made the difficult but appropriate recommendation to euthanize her.”

Bana was the dominant female in the family gorilla troop led by silverback Kwan. With her death, the family troop now has six gorillas. They were able to visit with Bana after she died, as they would naturally do in the wild. Some of the gorillas chose to touch her body, others did not, Cieslik said. The family troop is kept separately from the zoo’s all-male bachelor troop, which boasts three gorillas.

The median life expectancy of a female western lowland gorilla raised in a zoo is is 39 years, but they can live into their 50s. In the wild, their life expectancy is typically 30 to 40 years, according to Cieslik.

Bana was born at Brookfield Zoo in 1995 and came to Lincoln Park Zoo in 2010 under a species survival plan that matches potential mates to help perpetuate the critically endangered apes. There have been 56 births at the zoo since the first one in 1970.

Bana became a reliable participant in the cognitive touch-screen programs at the zoo’s Regenstein Center for African Apes and would often make sure she could go first, according to the zoo.

In 2011, Bana, then 16, gave birth to a female, Patty. Her pregnancy was confirmed, in part, by dipping a human pregnancy test in a urine sample. In 2019 she gave birth to a male named Djeke. Djeke was part of Bana’s family troop. Patty has since been transferred to another zoo.

“Bana was not only a great mother, but she was very tolerant of her youngsters and other youngsters in the group playing on top of her. She loved spending time in the outside yard and sometimes could be seen foraging out there by herself,” said Jill Moyse, curator of primates.

“Bana has left an undeniable mark on the hearts of zoo staff, volunteers and visitors, and played an important role in her own troop,” Moyse said.

There has been an outpouring of love toward Bana and staff at the zoo on the zoo’s social media pages.

A total of 29 western lowland gorillas have passed away at Lincoln Park Zoo since the first death was recorded in 1951, Cieslik said.