A ten-year-old 400-pound gorilla named Denny hurled himself at visitors on Saturday with such force that ‘It literally felt like an earthquake before we realized that that was just him hitting the glass’
An enraged gorilla terrorised zoo visitors after the beast charged around its enclosure[1] before shattering its glass walls.
Onlookers at the San Fransisco zoo recoiled in terror as 400-pound Denny[2] threatened to break free from his pen on Saturday 11 October.
Families dispersed as ten-year-old Denny hurled himself full force at the glass. “It literally felt like an earthquake before we realized that that was just him hitting the glass,” visitor Jackie Doubler told 10News[3]. “It was pretty scary. There definitely were people there quick though – security guards. The zoo handled the situation well. If he would hit that glass again, I definitely feel like it would have been a whole different story though.”
The zoo[4] said that the glass – made up of three layers of tempered safety material – was in tact apart from one layer and Denny was uninjured.
The gorillas in the Forest habtitat enclosure have been moved whilst the glass is fixed. Denny’s outburst came just weeks after the death of his older brother Maka, a 30-year-old western lowland gorilla who died unexpectedly in August after suffering a cardiac event.
Zoo officials said in a statement that the behavior is not unusual for gorillas of his age. “It is common for male gorillas, especially in adolescence, to express these types of behaviors,” a spokesman said. “Bursts of energy, charging, dragging items, or running sideways are all natural for a young male.”
Dr Erin Riley, a primate behavior specialist and anthropology professor at San Diego State University, told CBS8[5] that “charging displays” are typical gorilla behaviours.
She said: “Gorillas, particularly males, will often do what we call ‘charging displays,’ as a kind of act of showing off. One of the things gorillas actually don’t like is to be stared at directly in the eyes, and that’s not something that zoo visitors always understand.
“Given that it was directed towards the window, which is where the visitors are, I don’t know if they were feeling threatened, if there were a lot of people there that made Denny feel a little bit threatened.”
Dr Annie Petersen, an animal behavior and bonding expert added: “It may not necessarily have been an aggressive reaction; it may have been one of excitement, it may have been one of exploration,’ Petersen said.
In the wake of the incident the zoo has urged vsitors to be be cautious around the zoo animals.
“They’re super strong. We need to be respectful of them, and also respectful of their space,” said visitor Andrea Corry.
“A lot of people hit the glass, tap it, try to provoke them, and we need to just observe – watch them, not aggravate them.”
Western lowland gorillas are the largest primates in the world[6], standing up to six feet tall and weighing as much as 500 pounds, according to San Diego Zoo. The species is critically endangered in the wild due to deforestation and poaching across central Africa.