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Using animals to predict natural disasters like hurricanes, earthquakes, and tsunamis
Biologists find some animals get early warnings on natural disasters
By David Fleshler
Staff Writer
Posted January 13 2005
Source
As hurricane after hurricane struck Florida last year, animals showed a striking ability to predict catastrophe and get out of the way.
When Hurricane Charley came within hours of the Caloosahatchee River, eight sharks tagged by biologists suddenly bolted out of the estuary to the safety of the open ocean.
When Hurricane Jeanne approached Gainesville, butterflies in an experimental rain forest wedged themselves under rocks and disappeared into tree hollows.
And as the whole series of hurricanes churned through the state, birds appeared to delay their migration south, stacking up somewhere north of Florida until the route to their winter habitat was safe.
Like the elephants, buffalo and deer of South Asia that fled to high ground well ahead of last month's tsunami, many Florida animals have shown they can predict hurricanes and take steps to survive them.
While there was talk that the Asian wildlife displayed a "sixth sense" in anticipating the huge waves, scientists say animals may simply have a more acute ability to detect vibrations, smells or changes in barometric pressure. Until the past few decades, when humans invented weather satellites and seismographs to extend the range of their own crude sensory organs, it may be that animals had the advantage in avoiding natural disasters.
"It doesn't make any difference if it's a hurricane, a fire or an earthquake," said Frank Mazzotti, a wildlife biologist at the University of Florida. "They apparently sense these things before humans can do that. Not a lot of work has been done to learn the sensory mechanisms. It's likely a combination of smell, vibrations and pressure. They start moving away from danger before humans pick it up."
Hurricane Jeanne was several hours away from Gainesville last September when University of Florida biologist Thomas Emmel noticed butterflies taking shelter among rocks and trees in the university's enclosed rain forest. He suspects they could detect changes in barometric pressure with eardrum-like organs on their abdomens. Because air pressure decreases before a storm, this ability allows them to avoid being torn apart by high winds.
About 12 hours before Hurricane Charley struck southwestern Florida, scientists at Mote Marine Laboratory noticed odd behavior among sharks they had tagged in Pine Island Sound. As underwater hydrophones listened, eight of the 10 sharks headed swiftly out to sea.
Michelle Heupel, staff scientist at the lab's Center for Shark Research, said she suspects the sharks sensed the drop in air pressure and instinctively headed for the safety of the open ocean.
"If they get caught in the storm surge or big wave action, they could get bashed around or pushed ashore," she said. "What we've been finding fairly consistently, that sharks in coastal areas actually leave the area as storms approach."
While sharks fled the area, migratory birds may have delayed their flight through Florida until the hurricanes passed.
Fred Griffin, a Broward County birder, said it appeared that birds waited until October, very late in the season to head south into Florida.
"Once the hurricanes got through, it seemed like the migration really started," he said. "You have to figure they were hanging around and waiting for the atmosphere to clear out."
Douglas Levey, professor of zoology at the University of Florida, said birds have the ability to time migrations to take advantage of trailing winds and avoid headwinds. As with other animals, he suspects it's through detecting changes in air pressure.
"Nobody is out studying birds during a hurricane," he said. "But we can tell you that a lot of birds survive. Nobody has ever been able to tell where they go during a hurricane. But it's safe to say most of them find shelter."
The hurricanes of 2004 avoided the southeastern tip of Florida, home to endangered American crocodiles. But judging from past experience, the reptiles would have known how to handle whatever nature threw at them.
In 1992 Hurricane Andrew scored a direct hit on the crocodiles that live in the cooling canals of the Turkey Point power plant in southern Miami-Dade County. But when the storm passed, not a single dead crocodile was found. No one knows where they went, whether to open water or the bottom of 20-foot canals.
"There was no diminishment of nesting activity," Mazzotti said.
Not all animals could avoid danger. Last year's hurricanes wiped out about half the sea turtles nests in Florida, washing them away or burying them in sand. Many bald eagles returned to the state this winter to discover their nests were destroyed. After one of the hurricanes that passed over Lake Okeechobee, 30 to 40 dead alligators were found along the northwestern shore, Mazzotti said.
Among experienced hunters and fishermen, it's well known that animals show themselves more in the days or hours before a hurricane, as they pack in calories before the storm makes it hard to find food.
"When you go fishing before a storm, they bite like crazy," said Bouncer Smith, a Miami Beach charter captain. "Snook, grouper and tarpon feed very aggressively because storms cause them to relocate and make the water dirty."
As he bow-hunted in northwest Palm Beach County the day before the arrival of Hurricane Charley, J.R. Muguerza saw a huge buck with a nine-point rack emerge from the forest. He shot it dead, crediting the approaching hurricane with drawing out the big animal.
As he hunted, he was struck by the number of deer and hogs scurrying around the pine trees and palmetto bushes trying to stock up on food before the storm.
"They're feeding and running around," he said. "It was like somebody rang the dinner bell."
� Copyright 2005 Sun-Sentinel Co. & South Florida Interactive, Inc.
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