People for the Ethical Treatment of Animals has blasted CBS’ summer series Zoo on the eve of its debut, after reading news reports in which the producers bragged about using actual wild animals whenever possible – in marked contrast to assurances PETA says CBS gave them about doing just the opposite.

“By producing a show that exploits wild animals, including lions, CBS has proved that it’s out of sync with public opinion at a time when people are shunning SeaWorld’s captive orca sideshows, states and counties are passing laws banning wild animal acts and private ownership, and Ringling Bros. is taking elephants off the road,” PETA said in a statement this morning.

“Lions belong in the wild, not confined to tiny cages and forced to perform tricks, often under the threat of beatings,” PETA continued. “CBS should employ only humane and versatile computer-generated imagery, as so many other productions have done. PETA hopes Zoo will be one of this summer’s first cancellations.”

Based on the bestselling novel of the same name by James Patterson, Zoo details a wave of animal attacks against humans around the globe, a biologist who is trying to figure out why, and a journalist who is covering the mystery.

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PETA SVP Lisa Lange told Deadline the org met with CBS reps at Black Rock in January to discuss the series. At that meeting, “they told us they were doing everything they could to limit the use of wild animals in the show.” CBS execs promised, Lange said, they would not use live chimpanzees or live elephants at all in the production, for which she said she gives the network credit. “We were pleased with that. We are not, however, pleased they are using lions.”

The PETA exec said they were particularly put out when, after receiving CBS’ assurances the use of wild animals would be kept to an absolute minimum, they read news reports – like one in the Times Picayune, based in New Orleans, where much of the show is shot – about how much fun it will be for viewers to track “whether individual attacking animals are real or computer-made.” In that report, show executive producer Michael Katleman is quoted saying the production “had been going for real whenever it could.”

“We take the approach in every action sequence, every animal sequence, of ‘Let’s use real animals’,” he is quoted as saying in that report, adding, “Everyone is extremely concerned about the safety of the animals, our trainers are really safe.”

“That runs counter to what they told us,” Lange told Deadline. We reached out to CBS reps for comment; no response yet.

At a May press junket for the show in Los Angeles, actor Nonso Anozie said, “I did think we were going to work with a few more animals than we actually did,” but assured reporters, “First day you turn up, two live lions in front of me. So it was really a baptism of fire.”

In contrast, star James Wolk assured reporters, “All the animals that we’ve had down on set — and it’s been tons of animals, because it should also be said there hasn’t been a ton of CGI, there’s been a lot of real animals on set.”

“They all come with trainers,” Wolk continued. “They’re all incredibly well-trained, as far as wild animals go. They can’t talk, but they’re well-trained animals and all the proper precautions are taken” in order to enhance “the comfort level for the actors.” He added, “Your palms start to sweat, your heart starts to beat and you can’t help that when you’re around a lion or a bear. “

EP Jeff Pinkner added back in May, of the wild animals used on set, “one of the fun things is they’re actors, but they’re animals. And so you can’t — they can be trained, but when the moment happens, they don’t necessarily behave the way you’re expecting.”

When a reporter wondered, “Are there going to be attacks or are we going to see more action of animals attacking humans?” EP Scott Rosenberg assured, “Listen, we all love animals and nobody wants to create an environment that is anti-animal.”

But, he added, “We want the whole world to fear their Schnauzer – then we’ve done our job right.”