"Oh my god. That is heartbreaking. Oh, this is despicable. I am so horrified by what I'm seeing!"
Humane Society Investigator Jane Garrison is talking about Terry, the chimp.
"Hi bud," she says, trying to get Terry's attention through glass.
The lone chimpanzee at the Las Vegas zoo has often been featured as a star attraction.
But Jane says he lives a tortured existence.
"The cruelest thing that you can do to a chimpanzee is keep him in solitary confinement. He's emotionally just void. He's bored. He's depressed. This chimp has to get out of here."
Like the chimp, this lion is also alone.
"I've observed them in Africa. I've observed them in their homelands. They're social animals. You never see them alone. So to see that female lion alone in that barren enclosure was really, really heartbreaking," Jane says.
In fact, the image of two lions together is still used on the zoo's website to attract visitors, along with the caption, "Brother and sister love living at the zoo!"
There's no mention that the brother died of cancer almost two months ago.
Garrison, the California-based exotic animal specialist, says her overall impression of our unaccredited zoo is that..
"This is a huge black eye on Las Vegas and that this zoo should be closed immediately and people who care about animals should never, ever give them their money and go to that zoo."
Space is a major concern.
"They're in these tiny enclosures with no enrichment. It's torture for these animals and it's just not acceptable," she says.
She also can't accept that the San Diego zoo sends animals to Las Vegas.
Animals like Niya, the 3-year-old Siberian Lynx.
Jane says, "The Humane Society plans to contact the San Diego Zoo and not only agree to never send animals to this zoo ever again, but also to take back all the animals who are there on permanent loan and get them into a better facility."
We watch Niya constantly pace back and forth in her tiny cage.
"It means that their needs aren't being met either physically, socially, mentally... this cat is very stressed out, very, very stressed out."
She says the birds are too.
"See the feather loss all along the front of the bird? These birds are pretty stressed. That one is missing all the feathers completely in the front. The macaw up there is almost completely bald."
And some have nothing to walk on but wire.
"Walking on this fencing is not good for the bird's feet."
Jane highlights other concerns, like murky, dirty water for the zoo's otter, which she says is unsanitary and a health hazard. One of her chief concerns, however, is the heat.
The discomfort is obvious with almost every animal, from the birds to the binturong to the cougar... to the apes.
"That one has his tongue hanging out," observes Contact 13's undercover photographer.
"Yeah, it's hot. It's just so hot. I mean they don't have any way to cool off. They don't have a pool, they don't have misters," Jane explains.
And most of the enclosures don't have covers.
"Bottles, stones, rocks, all types of things are thrown over the walls because there's no covering," says local animal welfare activist Linda Faso.
Past media accounts show it's been that way for at least 15 years.
"If you can't do it right, it shouldn't be done," Faso says.
Contact 13 called zoo director Pat Dingle to ask for an interview and he invited us to come down to the zoo. When we arrived at our scheduled interview time, he wouldn't come out of his office, wouldn't talk to us at all, and had another zoo staff member present us with a written statement.
It says "Everyone has an opinion. We'll leave it up to the tens of thousands of visitors and members who enjoy the zoo every year."
It also notes that the zoo "has been licensed and inspected by federal and state agencies for more than 25 years" and remains "in full compliance of all regulations and standards."
Faso says, "That's a cop out, because by law the USDA only has to regulate zoos, circuses, puppy mills once a year. If they find anything in non-compliance then they come back and say fix this, fix this, fix this. All the USDA does is document and create paperwork and tell them to do better."
Contact 13 obtained the last five years of USDA reports for the zoo which show repeated problems and non-compliance.
"Oftentimes it's unsanitary housing, it's inadequate housing, it's no proper shade for certain animals. In the wintertime there's been documentation of some animals with frostbite. They wrote him up for not following vet's orders on what they recommended for animals, not calling vets when they said he should have, so it's just been an ongoing series of those kinds of problems which tells me it doesn't get better," says Faso.
We also documented rodents running rampant with our hidden camera, a health hazard the USDA has written the zoo up for repeatedly.
In a phone conversation, Pat Dingle told Contact 13 he is probably the zoo's harshest critic, even more so than the Humane Society. He says he's been fighting for more space and better funding for the last 29 years, but doesn't have the support he needs from the Las Vegas public.
"If they can't afford to have the proper social groupings, if they can't afford to give the animals enough space for each species, if they can't afford to give them adequate shade, if they can't afford to give them proper ways for them to cool themselves, then these animals can't afford to stay there," Jane says.
"And this zoo needs to recognize that and allow the Humane Society to place these animals in a better facility and we would be thrilled to do that."
The Humane Society has already found a Texas sanctuary called the Black Beauty Ranch that may take Terry the chimp. They also plan to meet with Las Vegas officials to pursue closure of the zoo.
Many people probably don't know that the zoo is privately-owned. Pat Dingle started it as a pet store more than 20 years ago.
He's turned it into a non-profit corporation that relies on private donors and members for money. He did get a community development loan from the City in 1989 but defaulted on it and ended up in a lawsuit.