Some startling creatures have taken up residence along a deserted back trail at the Minnesota Zoo. A 30-foot-long monarch-striped caterpillar and a horse-sized praying mantis ready to pounce make you feel as though you've just stumbled into "Land of the Lost."

But no worries. These two giant insects are made of rebar, plaster, concrete and painted epoxy.

They're being created by the zoo's shop crew to add a Minnesota-centric element to the traveling "Big Bugs" animatronic exhibit that opens Memorial Day weekend as the zoo's special summer attraction. A mosquito will join the ranks, of course. (At only 2 feet long, it'll be closer to life-size.)

The crew is also creating a walk-through interactive log that will feature info on millipedes, termites and other denizens of the damp woods. A nearby "bug house" filled with live insects — many of them trucked in from far-flung places — will supplement the giant fake ones.

A roving band of street performers will act out spontaneous skits around the zoo grounds to drum up even more buggy curiosity.

Like larger theaters and art museums, modern zoos have their own version of prop and scenery shops, making everything from special exhibit structures to fake trees that the crested oropendolas, a kind of tropical bird, will want to hang their basketlike nests from.

A praying mantis waits for its paint job.

But the zoo's exhibit builders face a couple of added challenges not as common for theaters and museums. For one thing, their creations must be able to withstand pummeling by hundreds of children a day.

"Big Bugs" has a giant spider, but not one you can touch. The zoo crew is building one with a web made of rubberized rope so visitors can pose for selfies as "victims."

Also, the builders must be sure that whatever they make is safe for the animals and aesthetically appealing to visitors.

"It can't be made of toxic material," said Jessica Madole, the zoo's interpretive program developer. "And you also have to cover it up with foliage so it doesn't show."

Like other cultural institutions trying to draw more visitors in an entertainment-glutted world, zoos have had to up the ante on providing eye-popping spectacles, because visitors expect and demand that. Just as art museums pack in visitors with pop-culture exhibits such as "Star Wars," animatronic crowd-pleasers such as last year's zoo dinosaurs and this year's bugs lend a bit of that theme-park "wow" factor.

So how can that reality be balanced with a mission that's all about providing education and promoting conservation?

Madole said the zoo's primary purpose is still to enhance the live-animal-viewing experience.

"We're unique from museums in that, even though we have a lot of the same kind of interpretive graphics, presentations and exhibits they do, the heart of what we do is still focused on the animals," she said. "Because at the end of the day, that's what people come to see.

"The best kiosks in the world can't compete with two bears who suddenly decide to start wrestling."

Kristin Tillotson • 612-673-7046