A powerful earthquake measuring 7.2 on the Richter scale recently struck Haiti, resulting in numerous casualties. Amid the news of this disaster, a recurring question arises: can we predict earthquakes through animal behavior?
Animal Prophets
According to the United States Geological Survey (USGS), the earliest reference we have regarding unusual animal behavior prior to a major earthquake dates back to Greece in 373 BC. It is believed that mice, weasels, snakes, and centipedes left their burrows seeking safety days before a devastating earthquake.
There is extensive evidence of animals, fish, birds, reptiles, and insects displaying strange behaviors anywhere from weeks to seconds before an earthquake. In many instances, warnings from animals have saved humans from disaster. The story from Haicheng (Liaoning, China) in 1975 serves as a prime example.
Despite freezing temperatures, numerous snakes slithered out of their hibernation spots in the weeks leading up to the 7.3 magnitude earthquake that struck Haicheng on February 4, 1975. The behavior of these reptiles, along with other incidents, convinced authorities to evacuate residents just hours before the disaster occurred.
Animals have long been believed to sense earthquakes early.
For centuries, humans have documented unusual animal behaviors right before earthquakes: dogs barking incessantly, cows refusing to be milked, frogs leaping ashore… to investigate whether animals can predict earthquakes. In a 2013 study, German scientists filmed red wood ants nesting along a fault line and discovered that they altered their daily habits before the earthquake, becoming more active at night and less so during the day.
In another study, scientists from the Max Planck Institute for Animal Behavior and the University of Konstanz, both in Germany, along with a multinational team, used highly sensitive biological sensors to monitor the activity of a group of livestock before an earthquake occurred. Over a period of four months from 2016 to 2017, they attached GPS sensors to six cows, five sheep, and two dogs living on a farm in a seismically active region of northern Italy.
A total of more than 18,000 tremors occurred during the study period. Analysis showed that the animals’ activity significantly increased before earthquakes measuring 3.8 or greater on the Richter scale when they were confined together in a pen. The farm animals seemed to predict tremors from one to 20 hours in advance, reacting earlier when they were closer to the epicenter and later when they were farther away.
What Reliable Explanation Exists?
Researchers believe that these findings support the hypothesis that animals can somehow perceive ion diffusion signals from geological activities. In the days leading up to an earthquake, tectonic plates shift, compressing rocks along a fault line, causing them to release minerals that push ions into the air. Animals are believed to sense this and react accordingly.
Meanwhile, a post on the USGS homepage suggests that unusual animal behavior is related to two types of seismic waves generated by an earthquake event: P-waves and S-waves. P-waves have a shorter wavelength and travel faster than S-waves. Many animals with more acute senses may detect P-waves seconds before S-waves arrive.
Before the earthquake in Haicheng (China) occurred in February 1975, many animals in the area exhibited unusual reactions.
However, these remain preliminary conclusions, and further research is needed to clarify the matter. “Most of the evidence is primarily based on isolated observations or even anecdotes,” a report published in 2018 by the Seismological Society of America stated after reviewing 180 studies on unusual animal behavior before earthquakes.
Wendy Bohon, a geologist at the Geological Research Institute in Washington, also expressed skepticism about these hypotheses. “My cat may act strangely before an earthquake. But it also behaves erratically if it hears unusual noises. To use animals as a basis for prediction, it is essential to determine that they exhibit unusual behavior solely in response to seismic events,” Dr. Bohon stated.
An illustration of the study conducted by scientists regarding the relationship between livestock responses and earthquakes in northern Italy.
Unfortunately, the consistent and reliable behavior of animals before seismic events, along with a valid explanatory mechanism for such behavior, remains an open and complex question. Nonetheless, the search for a connection between early animal responses and earthquakes continues, with the hope that humans will be able to predict such disasters sooner.
