Scientists: Bird in advance feel the approach of a hurricane – BBC Russian

• December 19, 2014

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Tornadoes in April 2014 led to the deaths of 35 people and caused damages worth over a billion dollars

American scientists have found that the birds “hear” the approach of a tornado and leave their nesting places for the day before the disaster.

Researchers examined data from sensors attached to songbirds and found that in April 2014 the bird flew 700 km to the south of the Gulf of Mexico, and the next day the central part of the United States swept a wave of deadly tornadoes.

Before you embark on this journey, the birds have returned from seasonal 5,000-kilometer migration.

Environmentalists have suggested that songbirds along with other individuals feel the approach of extreme events due to excellent low-frequency hearing.

Unprecedented flight

The researchers attached sensors 20 songbirds of the genus Vermivora in May 2013. After wintering in Colombia 10 birds sensor returned to the US in April 2014.

“This is a very small songbirds – they weigh about nine grams. And what they came back with geolokatorami, was a great success in this season, “- said the Air Force Dr. Henry Striba the University of California.

The team observed the birds, when she received a warning of the approach of a tornado.

For the observations, scientists have chosen zolotokrylyh Vermivora

A powerful storm brought with it a minimum of 84 tornadoes that caused the deaths of 35 people and caused damages worth over a billion dollars.

After the storm, scientists have caught five birds with geolokatorami and removed from their device.

These tiny devices weighing half a gram measures light levels and allow scientists on the basis of a certain time of the day and longitude to determine the approximate location of the birds.

In this case, the sensors indicated that the birds have made an unprecedented flight a day or two before the hurricane.

“Songbirds, which we studied, flew a total of at least 1,500 kilometers, – said Dr. Striba. – They flew south from the trajectory of the hurricane. And to 2 -th May all five birds returned to their breeding “.

Infrasound

Scientists amazed that the evacuation began when a tornado was coming at a distance of hundreds of kilometers. Weather conditions in the area of ​​nesting birds were quite common.

84 tornadoes have been recorded over the United States in the period from 27 to 30 April 2014

Most likely, the tip for birds served as a low hum, which produces a tornado. This sound is significantly below that which the human ear can hear.

The noise in the infrasonic range extends for thousands of kilometers, and can serve to some extent, an early warning system for animals that can catch it.

According to Dr. Striba, songbirds – are not the only creatures that can detect such signals.

Even at the household level observations was quite obvious that the day before the hurricane approaching the number of birds has decreased dramatically, he says that indicates the presence of abilities “anticipate” element in other species of birds.

Dr Chris Hewson, senior ecologist British Ornithology Foundation, also told BBC BBC that “infrasound”, most likely, is the most likely explanation of this phenomenon.

According to Hewson, some birds, including falcons, guided by infrasound.

To see a tornado in the United States – are not uncommon

“Based on the weather conditions, the other obvious signals, which could be guided bird, no,” – said Hewson, adding that the results of the study in a sense, “open your eyes” scientists.

At the same time, ecologists clarify that the study has an error associated with the location-based devices. Place the birds were determined by the lighting level, and not on the basis of satellite data.