Nature’s Weather Forecasters

Do animals have built-in weather detectors? 
Nature’s Weather Forecasters

23rd of March was  World Meteorological Day. Before the discovery of sophisticated weather forecast equipment and satellites, it was simply animal and plant behaviour that had warned our ancestors of weather changes. Animal behaviour can still be used to predict weather, and ZooLander looks at some of the animals that have the ability to predict weather patterns.
Today meteorologists use satellites and there are state-of-the-art weather stations around the world to monitor the weather, and for forecasting. However, even with  the modern technology of  today, there are so many variables, that 100% accuracy in weather forecasting is difficult. But our ancestors with traditional knowledge could predict the weather by animal and plant behaviour, with acumen gained from generations before. Some farmers even looked at these nature’s signs to decide on when to cultivate and surprisingly these signs often were accurate.
Birds, bees, colours in the sky, formation of clouds and the colour of falling rain, are some of nature’s signs for predicting weather.
The swallows are perhaps the most common weather forecasters known to  many Sri Lankans. Their Sinahala name wehi lihiniya translates into English as ‘rain bird’. It is believed that if they fly low, then rain will follow by evening. This prediction is often more accurate than weather forecasts that are relayed over TV  or Radio. But how do swallows know that it would rain? Or is this   just another myth?

Wehi lihiniya - or rain birds
Zoologists who studied the movements of swallows found that there is actually a scientific basis to their behaviour. Swallows that often fly high, come down mainly because the insects which they feed on, descend to lower levels on rainy days. Scientists explain that this could happen due to changes in  ‘air pressure’ shortly  before rain. The impact of air pressure could control the movements of the little insects, more than that of birds, resulting in the swallows having to come down to feast, just before it rains. It is in fact the insects that sense the change, but it is the wehi lihiniya that gets the credit in issuing the warning about the oncoming weather changes -- in the manner of a skilful meteorologist.
Scientists have conducted research on several species of birds, and confirm that they are able to foretell the weather, although it is yet to be established, to exactly what degree. In other countries this phenomena has also been tested with some other birds like the black cockatoos. It is said that these birds will fly down from hills and mountains and will glide towards coastal areas, particularly in the early mornings when heavy rain and storms are imminent. A further explanation for this behaviour could also be the changes in plant behaviour such as  opening of  seed pods in certain trees, due to the changes in air pressure.

Birds’ nests too could give clues
In some villages in India, the village folk look at a particular bird species to have an inkling  about the upcoming rainy season. This bird builds nests on trees and if the nests are toward the top of the trees, then heavy rains follow. But if they are lower down, there will be less rain think these villagers with centuries of experience. An Indian researcher having studied this phenomenon also found that the basis could be interpreted as, when the nest is near the centre of the tree, close to the trunk, it means heavy rains. But if birds build their nests on the tips of the branches, it means scanty rains and a drier season and the birds do not have to worry too much about getting their nests destroyed by heavy rains and winds.

Fish
Both saltwater and freshwater fish have been known to change their behaviour prior to weather changes.  An explanation put forward is that shallow dwelling species such as the plankton can sense atmospheric pressure and temperature changes, and change their behaviour.  This may then trigger a reaction along the food chain.
Many species of fish will ‘bite’ prior to an intense change in the weather.  Quite often fish will swim nearer to the surface and will take bait quickly before the rains come. Several species of freshwater fish that frequent the upper reaches of rivers, streams and creeks are often caught near the mouths of rivers and creeks before flooding rain spells.
Researchers observed this type of behaviour among a group of sharks as they tracked the sharks’ movements during tropical storm Gabrielle and hurricane Charlie. When the barometric pressure dropped just a few millibars - an occurrence that causes a similar change in hydrostatic pressure - several sharks swam to deeper waters, where there was more protection from the storm.

Ants
Ants are the most reliable weather forecasters on earth, say researchers.  A change in the weather is inevitable if the ants behave in a manner which is out of the ordinary.  They will be extra industrious and work frantically to clean out nests, construct and move into new nests, and gather food, when heavy rains are on the way.
Ants building cones or crowns around their nests on the ground, is an excellent indication that rain is on the way.  When ants build nests on top of fence posts or old stumps, rain is imminent, as per  folklore. Nests can also be found in or around any object that the ant deems to be higher than ground level --  when rain is on the way.

Do animals have a sixth sense?
Yala National Park was severely damaged by the 2004 Tsunami. Lots of visitors to the park were killed, but very few  large animals had died. It is said that the animals almost ‘flew’ away from the marauding sea. It is said that elephants in Thailand had moved inland to higher ground, just a few minutes before the Tsunami. Scientists say the elephants could sense the vibrations in their feet. It could be the same in the case of  earthquakes when animals seem forewarned.
It is believed that birds and bees too can sense earthquakes. A few minutes prior to the earthquake, everything becomes completely still - no movement or sound.  Birds stop singing and chirping and flying around.  Insects cease making noises and moving about, and there is a total silence and stillness.  Seconds before the earthquake dogs will start howling and other animals become agitated.  After the earthquake has passed, the silence is felt again for a couple of minutes.
It is said that animals could be having a sixth sense helping them to make weather predictions. But scientist believe they just have the five senses which we all possess; however they are successful predictors that have more powerful senses helping them make accurate predictions...

Published on LakbimaNews on 01.04.2012