Cookie, the Brookfield Zoo's resident 80-year-old cockatoo, was in fine form Tuesday morning.
The last remaining member of the west suburban zoo's original animal collection when it opened in 1934, he squawked with excitement — a piercing, guttural cry better suited to Australian woodlands — when a couple of strangers, a reporter and photographer, visited the Bird and Reptile House office where he now spends his days.
He banged his head, more likely a gesture of crankiness or anger than of heavy metal fandom, his handler said. He raised up, puffed out his still-vibrant pink chest and pushed his crown feathers to their full height, an impressive display for any female cockatoos in the vicinity.
On the wall was a notecard that the bird, officially a Major Mitchell's cockatoo, had just received from a fan in Thailand. "I'm really glad to know you. You are such a long-lived and happy cockatoo," it said. "I wish you more more happiness."
But while Cookie appeared the picture of avian health, zoo staffers know that their prized bird battles many of the ailments that beset humans of a similar age: osteoarthritis, osteoporosis, cataracts and fading eyesight. He has been off exhibit since 2009, with a sign in the bird house's public area saying, "Happy Retirement Cookie."
I got to wondering about Chicagoland's elderly animal population when the Shedd Aquarium sent out a news release this summer celebrating Granddad, its 80-plus-year-old Australian lungfish, at the institution since its infancy and, the Shedd said, the oldest living fish at any aquarium in the world.
Which, I wondered, are Chicago's other oldest animals? And why should the newborns get all the publicity?
What I learned is that there are different ways to define old — raw years vs. relative to species, for instance — and that, as veterinary practices improve, zoos and aquariums are increasingly dealing with aging populations.
"Zoological or aquarium medicine is notoriously heavy on geriatrics because these animals live with us much, much longer than we generally expect them to live in the wild," said Dr. Bill Van Bonn, the Shedd Aquarium's vice president for animal health. "There are a lot of animals that would never survive this long in the great wild because they'd become someone else's meal" as their health diminished and reflexes slowed.
William Zeigler, Brookfield's senior vice president of collections and animal care, attributed much of the institutions' success to the transfer of practices and even equipment from the care of domestic animals and humans over to a zoo's animal population.
For instance: Brookfield's Maggie, 52, the oldest orangutan in a North American zoo, fought through a thyroid problem seven or eight years ago, taking the same medication humans do. In the course of treatment, she lost a lot of weight, and her coarse hair softened.
"You're seeing animals live a lot longer," Zeigler said. "Right now, you're seeing gorillas in their 40s becoming commonplace. You didn't see that 30 years ago."
But in the course of collecting information for this story, I also was reminded of a truth about aged animals. Just like grandma and grandpa, their continued presence cannot be taken for granted.
Keo, 55, who arrived at Lincoln Park Zoo in 1959 and was the oldest living male chimpanzee in a North American zoo, had to be euthanized in late September due to advanced cardiac disease and a greatly diminished quality of life.
And just last week, Rio, a 21-year-old river otter the Shedd had initially included when I asked for a list of long-lived animals there, had to be put down, as well.
The first time I talked to Van Bonn, Rio was fine. Monday, just a couple of weeks later, the animal was gone.
"A good example, huh?" he said. "We can't keep them around forever. The last time you and I talked she was pretty stable. But as is often the case, stable means compensating for things. She since then, really went downhill pretty rapidly," showing difficulty navigating stairs, an indicator of advancing arthritis, and repeatedly going for water, which often signifies kidney failure.
"To us it was pretty obvious that this was her time," Van Bonn said.
But making such a decision as a professional doesn't negate the emotions. "There were a lot of tears here last week," he said. "We've got folks who are still grieving."
Dave Bernier, Lincoln Park Zoo's general curator, said losing Keo was similarly hard, but "whenever we bring an animal in, we're committed to the animal for its entire life. ... Our last greatest responsibility to the animal is sometimes to make that decision based upon the quality of life."