San Diego Zoo Gorilla Shatters Glass Barrier in Sudden Charge

Visitors at the San Diego Zoo experienced a moment of alarm over the weekend when a 10-year-old western lowland gorilla named Denny charged at the glass of his enclosure, cracking one of the protective panels. Zoo officials confirmed that no one—human or animal—was injured in the incident, which they described as a natural display of adolescent behavior.

The event occurred Saturday at the zoo’s Lost Forest gorilla habitat, where Denny lives among a troop of gorillas. Witnesses told local outlets that the sound of the impact startled guests watching from the viewing area. On Tuesday, the zoo confirmed that one of the enclosure’s three layers of tempered glass had been broken during the charge.

“Natural Behavior” for a Young Male Gorilla

In a statement, the San Diego Zoo reassured the public that such behavior, while dramatic, is typical for a young male gorilla.

It is common for male gorillas, especially in adolescence, to express these types of behaviors,” the zoo said. “Bursts of energy, charging, dragging items, or running sideways are all natural for a young male.

The zoo added that the enclosure design, which includes multiple layers of reinforced glass, ensured that no one was ever in danger. “The panel that was breached is made up of three layers of tempered glass,” the statement explained. Only one layer was damaged during Denny’s charge.

Guests Startled but Safe

Although no visitors were injured, some onlookers described being frightened when the glass cracked. “You could feel the vibration when he hit the window,” one guest told NBC San Diego. “Everyone gasped and backed away.”

Following the incident, zoo staff temporarily closed the gorilla viewing area and boarded up the damaged panel. Denny and another gorilla have been moved to a behind-the-scenes habitat while repairs are made. The zoo did not provide an estimated reopening date for the exhibit.

Remembering Denny’s Family

Denny, who turned 10 earlier this year, is well-known among San Diego Zoo visitors. He was named after philanthropist T. Denny Sanford, whose foundation funded the San Diego Zoo Kids television channel.

The gorilla’s family has been part of the zoo’s long-running conservation and education efforts for decades. Just two months ago, the zoo announced the death of Denny’s older brother, Maka, a 30-year-old male who died of a cardiac event. Maka had been one of the troop’s dominant males and a fixture at the exhibit for years.

Western Lowland Gorillas: A Critically Endangered Species

Western lowland gorillas, the species to which Denny belongs, are classified as critically endangered by the International Union for Conservation of Nature (IUCN). The International Fund for Animal Welfare estimates that their population in Central Africa declines by nearly 3% each year due to habitat loss, poaching, and disease—particularly Ebola outbreaks that have devastated wild populations.

Native to the dense forests of Central and West Africa, western lowland gorillas are the smallest of the gorilla species but still among the most powerful primates on Earth. Adult males can weigh up to 400 pounds and are capable of displaying intense strength when threatened or excited.

Zoo officials said the incident underscores both the raw power of gorillas and the importance of respecting the natural behaviors of wild animals, even in controlled environments. “Our staff works every day to provide environments that support the physical and emotional well-being of the animals in our care,” the zoo said in a statement.