The exhibit is enclosed by a low fence, allowing for great visibility for visitors, and has a moat as an added barrier because spider monkeys can't swim and are afraid of the water, according to the El Paso Times.
"Unfortunately, this may change all that because of this one lady's unfortunate actions," said Zoo director Joe Montisano.
Zoo staff found out about the trespass through a social media video that shows the woman attempting to feed two monkeys underneath a waterfall over the weekend. The zoo did not name the woman or detail the charges they plan to bring against her.
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"She's very fortunate that it didn't have a worse outcome for her or the animals," Montisano said. "These are primates. They are strong; they have canine teeth. They can scratch. We don't interact with them on the daily. And we don't interact with them without a barrier in between us."
Rob Lovett, of Lovett Law Firm, said Monday that the woman had been an employee of the law firm, but that she was terminated immediately.
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"The firm has always been a strong supporter of animals and advocacy. We absolutely do not condone this irresponsible and reckless behavior. We support the El Paso Zoo and our thoughts go out to the spider monkeys, Libby and Sunday, and we hope they recover from this traumatic experience," said Lovett.
Montisano said they will talk to the District Attorney about pressing charges.
"This young lady decided to hop a fence, climb through some bushes, drop down into a four-feet deep moat, walk across the moat and then try to feed the spider monkeys," Montisano said.
"We can't let this behavior go unpunished," he said.
The video in the player above is from an earlier report.