Southern California experienced a 5.2-magnitude earthquake on Monday morning, according to the U.S. Geological Survey (USGS), because of which a herd of elephants formed a circle. The tremor struck at 10:08 AM local time, with its epicenter located just 2.5 miles (4 kilometers) south of Julian, a small mountain town near the U.S.–Mexico border. The quake originated at a depth of eight miles and was followed by multiple aftershocks.
The quake was felt across a wide area, with tremors reaching as far north as Los Angeles County, approximately 120 miles (193 kilometers) away. Despite the widespread reach, there were no immediate reports of serious damage or casualties. Scientists noted that structural impacts were unlikely due to the quake’s magnitude and depth.
Elephants respond instinctively at San Diego Zoo Safari Park
While the quake caused panic among residents in Julian — a town of 1,500 known for its quaint apple pie shops — it also triggered a striking display of animal behavior nearly 60 miles away at the San Diego Zoo Safari Park.
As the ground began to shake, surveillance footage captured a herd of elephants swiftly forming a tight circle around their young — a behavior known in the animal kingdom as an “alert circle.”
“This instinctive formation is a protective maneuver designed to shield the herd’s most vulnerable members from perceived threats,” the zoo stated. “They remained in the alert circle for around four minutes before relaxing, though the herd continued to stay close together.”
What is an ‘alert circle’?
In the wild, an alert circle — also called a “flight distance” response — refers to the invisible boundary surrounding an animal within which it becomes hyper-aware of potential dangers, whether predators, humans, or sudden environmental changes like earthquakes.
If that boundary is crossed, animals may display a range of defensive behaviors including freezing, fleeing, or assuming protective postures. The size and intensity of this response can vary depending on the species, the individual animal, and environmental context.
Understanding such behavior is critical not only for wildlife conservation and observation but also for ensuring ethical and safe handling practices in zoological settings.
Tectonic tension along the U.S. West Coast
California’s seismic activity is driven by numerous fault lines crisscrossing the region, marking the boundary between major tectonic plates. Southern California has seen a number of destructive earthquakes over the decades.
One of the most devastating in recent memory was the 1994 Northridge earthquake in the Los Angeles area, which resulted in dozens of deaths, thousands of injuries, and billions of dollars in damage.
In a historical context, the 1906 San Francisco earthquake — and the fires that followed — claimed an estimated 3,000 lives and caused widespread destruction, making it one of the deadliest natural disasters in U.S. history.
The San Diego Zoo Safari Park has released the video of the elephants’ instinctive reaction to the quake, offering a powerful glimpse into the natural instincts that persist even in controlled environments. Experts say such moments underscore the importance of understanding animal behavior in both conservation and crisis settings.