Andrew Oberle a Victim of 'Territorial Defense' by Chimps

July 2, 2012 -- The South African chimp sanctuary where a Texas graduate student was mauled by two chimpanzees last week is safe and has not changed its safety protocols in the wake of the accident, officials said today.

"We still maintain that we are a safe facility," Eugene Cussons, director at the Jane Goodall Institute Chimpanzee Eden near Johannesburg, said today on "Good Morning America." "As far as our protocols go to ensure the safety of visitors coming here, it's still the status quo."

Cussons was one of the first to respond to the calls for help Thursday after Andrew Oberle, a 26-year-old graduate student who had been spending his summer conducting research at the institute, was attacked by two chimpanzees after he stepped into a restricted area while leading a tour.

His condition has been upgraded to stable.

Cussons, appearing on "GMA" today feet from where the accident occurred, provided a timeline of what happened in the first moments after he received word of the attack.

"I got the phone call from the sanctuary manager that said to me, 'Listen, we need to invoke lethal force protocol in order to save Andrew's life,'" he said. "So at that point I raced up with a vehicle, got to the scene, spotted the two chimpanzees, immediately jumped out of the vehicle and charged towards them with a handgun and fired two warning rounds into the air.

"Normally, this would chase any chimpanzees off that might be in attack mode but these two chimpanzees were highly motivated. They were hyped up. So I retreated back to my vehicle and fired a third warning round out of the window, right next to the chimpanzee that was now about 30 meters [about 100 feet] from me," Cussons said. "Finally, I closed my window up and the chimpanzee jumped onto the bottom of my vehicle and started beating through my windshield.

"I was then forced to fire a round at the chimpanzee, warning the chimpanzee because my intention at that point was that I needed to get to Andy so there was no other alternative option," he said. "The absolute necessity there was how to save human life."

After the fourth round was fired, the chimps moved away, allowing Cussons and first responders to get to Oberle, who suffered huge cuts to his head and face that left his skull and facial bones exposed.

Oberle, an anthropology major at the University of Texas at San Antonio, underwent six hours of surgery in a South African hospital Sunday. His parents arrived at the hospital from the United States. this morning to be with their son.

"As far as the information that we've received, he is in stable condition," Cussons said. "We are hurting at the sanctuary in the sense that we've witnessed a lot of things and we're very sorry for what happened and we're just so sorry for the family to have to endure this and for Andy to have to go through this."

The institute's internal investigation of the attack, launched immediately after the attack occurred, shows that the two male chimps, Nikki and Amadeus, responded to Oberle's crossing into a "no-go zone" in one of two fences separating him from the animals. Oberle did not have clearance to be standing in the area past the public fence, Cussons said.

"I think Andy made a judgment here by entering the 'no-go zone' and getting too close to the fence," Cussons said.