What Happens After Hours?

Moholi bushbaby and aardvark at Lincoln Park Zoo

Moholi bushbabies and aardvarks are among the zoo’s nocturnal species.

Shedding Light on the Zoo at Night

Do you light up the cages of nocturnal animals at nighttime, like the bushbaby and the loris, so they can be active and ‘play’?
—Grace Palacio, Zoo Visitor

"When the public leaves the zoo, what do the keepers do with the animals? Do they get a walk out of their enclosures or are they brought in to the buildings?
—Lauren Ofner Sadofsky, Zoo Visitor


Most animals end their day after the guests leave, hunkering down for a well-earned night of sleep. But what about the zoo’s nocturnal species? What do they do after dark? Read on to find out.


Day for Night

Many of the zoo’s nocturnal species reside at Regenstein Small Mammal-Reptile House. The Gallery section of the building alone includes La Plata three-banded armadillos, cactus mice, lesser Madagascar hedgehog tenrecs, pygmy slow lorises, Egyptian and straw-colored fruit bats and Moholi bushbabies (also known as galagos).

To ensure visitors will see these animals active and not snoozing, they are set up with a reversed light cycle. From 9 a.m.–7 p.m. the lights in their exhibit are on but very dim, simulating moonlight; from 7 p.m.–9 a.m. they’re on full blast. It’s the exact opposite of the schedule for the Gallery’s dirurnal (daytime active) species.

In some cases it makes exhibit maintenance a relative snap.

“When we want the galagos to go into their off-exhibit holding area, we turn the lights off in holding and turn them on in the exhibit,” says Curator Diane Mulkerin. “They automatically shift over.”

The bushbabies also have a habit of waking up around 6:30 a.m. “It’s the only time you can see them moving around with the lights on,” says Mulkerin.

Hoffman's two-toed sloth at Lincoln Park Zoo

Hoffmann’s two-toed sloths at Regenstein Small Mammal-Reptile House are more active at night in the mixed-species Ecosystem exhibit.

Visitors who’ve sought out the Hoffmann’s two-toed sloths and dwarf crocodiles and caimans in the building’s glass-domed Ecosystem know these nocturnal animals rarely move during sunlit hours.

“That’s why it’s a great idea to visit during ZooLights, when the building stays open late for the public,” says Mulkerin. “The crocodilians swim around more, and the sloths climb trees and all over the mesh.”

All-Access Pass

Unlike their wild counterparts, the African lions at the zoo don’t have to hunt at night. They’re a bit more active after-hours, though, says Curator of Mammals Mark Kamhout.

“Sahar is younger, so he’s more curious,” says Kamhout of the zoo’s 3-year-old male lion. “He’ll go outside in the evening and early morning. He’s very observant of everything around him.”

The big cats and other mammals with outdoor yards at the zoo have outdoor access at night and can go in or out. (The animals at the Farm-in-the-Zoo are an exception to the rule and are kept indoors overnight.) But they often prefer to hang out in their behind-the-scenes living spaces. “Those areas serve a purpose,” says Kamhout. “There’s hay bedding in there. That’s where they’re fed.”

The four young sisters in the zoo’s African wild dog pack—whose wild counterparts sometimes hunt in the early evening—often opt for a group nap in the late afternoon. “They pile up on each other,” says Kamhout. “It looks like one big wild dog.”

Patsy, the zoo’s female aardvark, sleeps even more during the day. Regenstein African Journey’s only completely nocturnal species, the long-snouted insect eater occasionally rouses herself to forage for mealworms, crickets and nutrient-rich grains. Her burrow is kept dimly lit during daylight hours to encourage this active behavior.

“To her, it’s kind of night time,” says Kamhout.

Tawny Frogmouth at Lincoln Park Zoo

Tawny frogmouths, native to Australia, represent the sole nocturnal species at the McCormick Bird House.

A Tawny Tale

Most of the winged occupants of the McCormick Bird House begin seeking out roosting spots for the night minutes after the public departs. But the building does have one bona fide nocturnal species: a tawny frogmouth male and female breeding pair (no chicks yet, though a chick was born to a previous pair in 2006) who make their home in the forest exhibit.

Often mistaken for an owl, this member of the nightjar family has dark gray and black feathers that blend into the bark of trees in its native Australia.

“As nocturnal animals, they camouflage really well,” says Sunny Nelson, the zoo’s Hope B. McCormick Curator of Birds. “When they’re alarmed, they go into an upright, erect position where their heads are elongated. It makes them look like a tree branch.”

Small beak tips peeking out from puffy feathers also disguise another impressive feature, the bird’s big mouth, which they use to hunt rodents and insects.

“We tend to offer them food later in the afternoon to give them a chance to forage around,” says Nelson.

“We can assess their nightly activity by what’s in disarray—wing prints, nest materials, where they’ve pooped,” says Nelson. “But by the time we arrive for our morning shifts they’re back to sitting on a log.”


By Craig Keller • Published December 27, 2013 • Originally published in Winter 2013 Lincoln Park Zoo magazine

baby klipspringer at Lincoln Park Zoo

A female klipspringer received around-the-clock care after her birth at Regenstein African Journey last September.

After-Hours Animal Care

Just as it does for us, night time means peace and quiet for the zoo’s animals.

Animal caregivers, from keepers to curators to veterinarians, have well-honed response procedures in place 24/7 in the event of an emergency. But the zoo doesn’t need lots of keepers hovering around habitats in the wee hours.

“At night, our animals don’t necessarily want us bothering them,” says Megan Ross, Ph.D., the zoo’s vice president of Animal Care. “They’re sleeping, so we’re not doing much for them then.”

There are certainly exceptions to the rule.

“When we have births, or if an animal is injured or sick, they receive around-the-clock care,” says Ross.

In such cases, keepers rotate in shifts. They made sure a newborn klipspringer born in September was fed throughout the night. They babysat female western lowland gorilla Nayembi as she recovered from a facial injury. (You can visit the rambunctious, fully healed little one with playmate Patty in their family troop at Regenstein Center for African Apes.)

Zoo staff also keep a close eye on unfavorable forecasts.

“We check the weather reports every day,” says Ross. “We’re not leaving animals outside if a storm is coming or temperatures are dropping.”

Learn More

Lincoln Park Zoo magazine Winter 2013 issue

Zoo FAQs
How does the zoo stay free? How are the animals paired up? Do the animals get bored? Where does all the poop go? We answer your most frequently asked questions in the latest issue of Lincoln Park Zoo magazine.