It was 8 a.m. on a weekday. Jay Knehans was in the kitchen, chopping, sorting and weighing out cantaloupe, celery, sweet potatoes, bananas and oranges into small bowls. A bin with grapes, peppers and lettuce was on standby.
There were 350 mouths to feed.
"I won't be done until lunch," he said, grinning. He's among 26 on staff at the St. Louis Zoo's Children's Zoo.
Every now and then he checked the laminated book propped open in front of him, telling him what to serve to which animal.
"The hornbill gets fresh produce, but also what we call Zulife pellets," said the veteran zoo keeper, of a special supplement for the tropical bird.
On a perch behind him, Bo, an African parrot, whistled a few bars from the "Star Wars" theme that Jay taught him.
A crowd watched from behind a big glass window as Jay and other keepers worked: Opossums have vitamins added to the dry cat food they prefer, as well as carrots. Twice a day.
Keeper Cassie Stanton made sure Edgar the parrot would get his whole Brazil nut and lettuce. He has to crack the big hard shell with his long beak to get to his meal. The keepers want it that way so he keeps up with his wild skills and stays busy.
Like parents dealing with picky children, keepers work hard to offer variety in food and to keep its presentation interesting.
"Some food will go in bowls, but some will be put out or hidden so they can forage," similar to what they would do in the wild, Jay said. "If they don't like something, that's no good. It's trial and error then. Sometimes it's the way (food) is cut or the size or even where you put it in the enclosure."
Pigs and goats, on the other hand, "will eat everything," said Cassie.
The kitchen refrigerator is stocked with frozen blueberries and corn, but you'll also find clear plastic bags of whole white mice and rats, fluffy yellow chicks and rabbits.
"That's for large birds of prey and bigger snakes," said Jay.
On the fridge door is the RTS: rodent thaw schedule. Carnivores like their meals minus icicles.
"The raptors' favorites are rabbits," said Cassie. Horace, a great-horned owl, gets a small bunny on Sundays. Saturdays, he dines on one medium-size rat, while if it's Monday, it's three mice and a chick. Skin, fur, feathers, bones and all.
"They eat them whole," explained Cassie.
Meals for 19,000
More than 3.5 million people visited the St. Louis Zoo in 2012, a record-setting number. Most are unaware of the time and attention spent by experts there on feeding the animals.
The Children's Zoo is unique in that it provides food to a variety of species. Other keepers have kitchens in their respective habitats throughout the zoo where, unseen, they sort, weigh, track and feed their wards. From tigers that eat nutrient-enriched beef to giraffes reaching for hay to reptiles that find crickets tasty.
The source of all this food for 19,000 animals originates at the Orthwein Animal Nutrition Center, tucked away near River's Edge. It's not open to the public, but visitors can see the work in progress through a long row of windows at the front of the building.
The warehouse-size center includes soaring ceilings and cavernous rooms where everything from as much as 40,000 pounds of capelin (a type of smelt for the sea lions) to frozen bones for the bush dogs and silos of "complete feed" pellets are stored until ready to ship out daily on small trucks and carts to each habitat in the zoo.
Nutrition workers start their day at 5:30 a.m. so the bulk food is delivered to keepers by 8 a.m.
On a weekday, volunteer and retired engineer Ken Gibbs, of Waterloo, spent a couple hours in the center's kitchen sorting, weighing and packing whole fruits and vegetables into gray tubs to be delivered over the weekend.
"That's about 700 pounds for Saturday and Sunday," he said. "And that's just produce."
As he worked, a familiar chirping came from small white boxes stacked near a stainless-steel table.
"Crickets," pointed out Deb Schmidt, the center's animal nutritionist. "They're for the reptiles and birds (like pelicans). And the Children's Zoo."
They're one of just a few kinds of food that come to the zoo alive. Even though they're dinner, the crickets get fed, too: crushed calcium-rich pellets that provides more nutrients down the food chain.
While there are set schedules for when some animals eat, others like the marmoset, a tiny monkey, eat constantly because of their high metabolism.
Some moths, depending on their stage, don't eat at all.
How do you feed a zebra?
Trying to feed an animal in a zoo what it ate in the wild isn't logistically possible, said Deb.
So, how do they know what to feed a zebra? You look at a horse, she said.
"We're trained in domestic animal nutrition," she pointed out. "We take them and use them as models: A horse for a zebra, for example."
And a cow for a giraffe? You bet. Both are ruminants, which means they have multi-chambered stomachs.
Fruits and vegetables come from restaurant suppliers to ensure their quality and cleanliness.
Animals are weighed and diets adjusted if somebody puts on a few ounces or pounds. It happens, Schmidt said.
"In a group setting, you have to overfeed a little" to prevent agitation and fighting, she said. Apes, for example, may get their greens and root vegetables scattered around their enclosures so there is less likelihood of conflict. But dominant members naturally get more of the fresh "highly prized" food.
The bulk of the food eaten at the zoo resembles cat or dog kibbles. But these pellets are specifically formulated to meet nutritional needs and called "complete feed," said Deb. There are primate biscuits, insectivore pellets, omnivore chow and more. Fresh food is added on top of that for variety. While orangutans get primate biscuits, they also may be served sweet potatoes, leeks and lettuce.
Adding "human" food to zoo diets is sometimes necessary, too.
Take Merah the orangutan and Joe the gorilla. Apes are the pickiest eaters, Deb said, and neither animal eats primate biscuits.
"Merah just doesn't like them," she said. And Joe may have an allergy to the wheat in them.
So what to do to make sure they consume the proper amount of nutrients?
Joe gets chewable vitamins. Merah gets gummy calcium (tablets).
"She thinks it's candy." Deb said.
Infant mammals, whose mothers can't or won't nurse them, are given pediatric electrolytes the first 24 hours. Then, they might get formula.
And the powdered drink mix Crystal Light is a good way to hide bitter medicine given to primates, said Joe Knobbe, zoologist and manager of the Primate House.
"Strawberry margarita mix works really well, too," he said with a grin. Minus any tequila, of course.
And Deb said applesauce is used to disguise medicine given to great apes.
Every animal loves a special treat. Nipper the sea lion will flap a flipper anytime senior trainer Angela Hamberg asks him to. He knows she'll toss him a herring.
Keepers offer rewards to animals for certain behaviors and as distractions, such as being moved to a holding area while their enclosures are cleaned, being weighed, checking on the young, even administering medicine.
"Lemurs love bananas -- all primates do," Joe said. "But, it's not a natural food in their habitat. Bananas are a high reward we use for training."
Hyenas adore coconut.
Anteaters enjoy avocados.
Deb said the nutrition center just got in some watermelons, an ape favorite.
And animals definitely have their own way of dealing with the food given to them.
While the biscuit feed is a diet mainstay for primates, some prefer theirs a little less crunchy.
"Chimps will take handfuls of water and take a big drink and soak them (in their mouths)," Joe said.
Sometimes an animal just goes off the menu and catches its own food.
"Tigers will catch a bird for fun," said Schmidt with a shrug of her shoulders. Then there was the chimpanzee that caught and killed a squirrel --and kept it around for a few days.
The dining experience
Joe at the Primate House likes the 70-plus animals there to work for their food. To visitors, it looked more like play as a lemur sat on the edge of an open cardboard box in an enclosure and rooted through a mound of straw to discover slices of carrots and chunks of lettuce hidden inside.
Zoo keepers also hang hollow balls for the spider monkeys, as well as baskets and wire-mesh wreaths -- all filled with fresh food for the primates. They're put just far enough away that some strategy is required in eating.
"It encourages stretching and reaching," he said. Pointing to a wreath stuffed with greens and strung too far off the ground to reach with tiny fingers, he said. "They have to hang by their feet to get that."
A crowd had gathered around the lemur enclosure, where a set of 2-month-old triplets scampered. Little Andrianna mimicked mom Lulu, who adeptly reached for and found food in another cardboard box.
"They'll see what Mom eats," Joe said as the little one fell head-first into the box, prompting visitors to laugh. She re-emerged with a carrot in her teeth.
"She's the bold one," he said with a grin.