European toads (Bufo bufo) may be able to predict earthquakes.
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The Bufo bufo changed its breeding pattern to avoid an earthquake.
According to a study recently published in the Journal of Zoology, toads may be able to predict earthquakes. In 2009, a group of European toads (Bufo bufo) – also known as common toads – abandoned their breeding site five days before the earthquake that devastated L’Aquila, Italy, and didn’t return for several days.
Scientists were studying the toads’ breeding activities at San Ruffino Lake, 46 miles from the epicenter of the earthquake, when they noticed the unusual behavior. The European toad is primarily terrestrial, but travels to the water each year to breed, and the males stay at the site until spawning is finished. Five days before the 6.3 magnitude quake on April 6, the number of male toads at the spawning site decreased by 96 percent, which is highly unusual. They returned about 10 days later, not until after the full moon had already passed. Previous research confirmed that the toads at the San Ruffino site normally breed around the time of the full moon.
Using data from a nearby weather station, researchers were able to rule out climate conditions as a possible reason for the toads’ behavior, leaving the earthquake as the most likely factor. It’s possible that the toads anticipated the earthquake due to unusual levels of radon gas in groundwater or changes in the Earth’s magnetic field.
Research of this type is very rare. Because earthquakes are nearly impossible to predict, scientists have been unable to study animals before and after these events. Most evidence has been based on individual reports after the fact. It’s also rare to find an animal that can anticipate an earthquake so far in advance. Usually, dogs, cats and other animals exhibit strange behavior several seconds before an earthquake hits. This is because they can feel P-waves, a type of seismic wave, while humans can only feel the seismic S-waves that occur a few seconds later. Snakes, fish and mice are among the few animals that have been reported to behave strangely several days before an earthquake.
The study concluded that the European toad probably left its spawning site for higher ground, which could have saved it from falling rocks, flood and landslides. After comparing B. bufo’s behavior to reports of other animal activity before earthquakes, researchers say it’s possible that some animals, especially those at greater risk during an earthquake, have adapted over time and found ways to predict these disasters days in advance.