Can Animals Sense
Earthquakes?
Maryann Mott
for National Geographic
News
The
belief that animals can predict earthquakes has been around for
centuries.
In
373 B.C., historians recorded that animals, including rats, snakes
and weasels, deserted the Greek city of Helice in droves just days
before a quake devastated the place.
Accounts
of similar animal anticipation of earthquakes have surfaced across
the centuries since. Catfish moving violently, chickens that stop
laying eggs and bees leaving their hive in a panic have been
reported. Countless pet owners claimed to have witnessed their cats
and dogs acting strangely before the ground shook—barking or whining
for no apparent reason, or showing signs of nervousness and
restlessness.
But
precisely what animals sense, if they feel anything at all, is a
mystery. One theory is that wild and domestic creatures feel the
Earth vibrate before humans. Other ideas suggest they detect
electrical changes in the air or gas released from the Earth.
Earthquakes
are a sudden phenomenon. Seismologists have no way of knowing
exactly when or where the next one will hit. An estimated 500,000
detectable quakes occur in the world each year. Of those, 100,000
can be felt by humans, and 100 cause damage.
One
of the world's most earthquake-prone countries is Japan, where
devastation has taken countless lives and caused enormous damage to
property. Researchers there have long studied animals in hopes of
discovering what they hear or feel before the Earth shakes in order
to use that sense as a prediction tool.
American
seismologists, on the other hand, are skeptical. Even though there
have been documented cases of strange animal behavior prior to
earthquakes, the United States Geological Survey, a government
agency that provides scientific information about the Earth, says a
reproducible connection between a specific behavior and the
occurrence of a quake has never been made.
"What
we're faced with is a lot of anecdotes," said Andy Michael, a
geophysicist at USGS. "Animals react to so many things—being hungry,
defending their territories, mating, predators—so it's hard to have
a controlled study to get that advanced warning signal."
In
the 1970s, a few studies on animal prediction were done by the USGS
"but nothing concrete came out of it," said Michael. Since that time
the agency has made no further investigations into the theory.
Erratic
Behavior in Dogs
Researchers
around the world continue to pursue the idea, however. In September
2003 a medical doctor in Japan made headlines with a study that
indicated erratic behavior in dogs, such as excessive barking or
biting, could be used to forecast quakes.
There
have also been examples where authorities have forecast successfully
a major earthquake, based in part on the observation of the strange
antics of animals. For example, in 1975 Chinese officials ordered
the evacuation of Haicheng, a city with one million people, just
days before a 7.3-magnitude quake. Only a small portion of the
population was hurt or killed. If the city had not been evacuated,
it is estimated that the number of fatalities and injuries could
have exceeded 150,000.
The
Haicheng incident is what gave people hope that earthquakes might be
predictable, says Michael, and what prompted the animal behavior
studies by the USGS.
It
was later discovered, though, that a rare series of small tremors,
called foreshocks, occurred before the large quake hit the
city.
"It
was the foreshock sequence that gave (Chinese officials) the solid
prediction," Michael said.
Still,
the Chinese have continued to look at animal behavior as an aid to
earthquake prediction. They have had several notable successes and
also a few false alarms, said Rupert Sheldrake, a biologist and
author of the books, Dogs that Know When Their Owners Are Coming
Home and The Sense of Being Stared At.
A
reproducible connection between animal behavior and earthquakes
could be made, he said, but "as the Chinese have discovered, not all
earthquakes cause unusual animal behavior while others do. Only
through research could we find out why there might be such
differences."
Sheldrake
did his own study looking at animal reactions before major tremors,
including the Northridge, California, quake in 1994, and the Greek
and Turkish quakes in 1999.
In
all cases, he said, there were reports of peculiar behavior
beforehand, including dogs howling in the night mysteriously, caged
birds becoming restless, and nervous cats hiding.
Geologists,
however, dismiss these kinds of reports, saying it's "the
psychological focusing effect," where people remember strange
behaviors only after an earthquake or other catastrophe has taken
place. If nothing had happened, they contend, people would not have
remembered the strange behavior.
Reporting
Strange Behavior
Sheldrake
disagrees. Comparable patterns of animal behavior prior to
earthquakes have been reported independently by people all over the
world, he said. "I cannot believe that they could all have made up
such similar stories or that they all suffered from tricks of
memory."
More
research is needed and is long overdue, said Sheldrake, who proposes
a special hotline or Web site where people could call or write in if
they saw strange behavior in their animals. A computer would then
analyze the incoming messages to determine where they originated. A
sudden surge of calls or e-mails from a particular region might
indicate that a quake was imminent.
The
information would be checked to make sure the observations were not
caused by other circumstances known to affect the behavior of
animals, such as fireworks, or changes in weather. And to avoid
issuing false warnings, Sheldrake said, the data would be used in
conjunction with other monitoring devices such as seismological
measurements.
"Such
a project would capture the imagination of millions of people,
encourage large-scale public participation and research—and would be
fun," he said. "What is holding this research back is not money but
dogmatism and narrow-mindedness."
http://news.nationalgeographic.com/news/2003/11/1111_031111_earthquakeanimals.html
November
11, 2003
National
Geographic News
Maryann
Mott
| 
