In 2011, 23 days before a 7.0 earthquake hit part of Yanachaga National Park in Peru, animals began to disappear from the forests, and then 24 hours before the earthquake hit, no animal movement was recorded. This is very unusual for an area that is usually filled with animal movement. This national park was about 350 kilometers from the epicenter of the earthquake.
Scientists used motion-capture cameras and also recorded the reflection of very low frequency (VLF) radio waves above the area surrounding the epicenter, to detect disturbances in the ionosphere. A particularly large fluctuation was recorded eight days before the quake, coinciding with the second significant decrease in animal activity observed in the pre-earthquake period. Rats seem to be more attuned to an early warning system. Eight days before the earthquake, there were no rats to be found, which is very unusual for this area.
In L’Aquila, Italy in 2009, scientists noticed unusual toad behavior in areas where atmospheric disturbances were detected that usually occur before earthquakes. Researchers believe that the animals in Peru and the toads in Italy could have been reacting to the same seismic phenomenon which was positive ionization of air molecules that results from the shifting of the earth’s crust. It is believed that the ions had an irritating effect upon the animals. Animals that are in captivity might become restless or become panicky as a result of the positive ionization. In seismic areas, people can react to positive ionization with signs of discomfort like headaches or nausea. Another reason why animals might also be reacting prior to earthquakes is the very low-frequency radio waves that come out of the ground before earthquakes happen.
Some researchers are hoping to further this study by looking at the biological changes in plankton ahead of major seismic shifts. To me, it would be quite interesting to see those results.
More work needs to be done to understand the warnings that animals can give prior to earthquakes. Just looking at animals to predict earthquakes is unreliable, so there still is a need for geophysical measurements in combination with animal measurements. There is so much we don't yet understand about animals. It is intriguing to study animals to find out all the talents that they have that are unforeseen to us humans. #earthquakes