WRITE DOWN TWO EXAMPLES OF DIFFERENT ANIMALS BEHAVIOR DURING TSUNAMI
Answers
Unusual Behaviour of Animals before Tsunamis!
As in case of earthquakes, animals start behaving in unusual manner, before tsunamis actually strike the coast. At the time of catastrophic tsunamis which wrecked havoc in Indian Ocean on 26th December 2004, elephants in Thailand started wailing. They soon calmed down, but started wailing again about an hour later.
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This time they could not be comforted despite their mahauts’ efforts. The elephants just kept running for the hill. The elephants that were not working broke their hefty chains. Soon the area was attacked by devastating tsunamis caused by the earthquake (8.9 on Richter Scale) of Sumatra.
Abnormal behaviour of birds and animals was also observed in the coastal belt of Tamil Nadu (the worst hit area in India). Animals in forests were feeling restless. Birds stopped crying and there was unusual silence. About two months before the tsunamis struck the Indian coast fishermen of Pondicherry found fish with reddish tails, called Red Bait, in their trawler nets. The sighting of this fish had always preceded a natural calamity.
Catches of similar type in 1977, 1979 and 1996 were followed by major cyclones. It is a fishermen’s instinct that Red Bait portends disaster and it has often come true. According to Central Marine Fisheries Research Institute (CMFRI), the Red Bait (measuring about 12 cm when fully grown and is edible) is a deep water fish which surfaces during ‘upwelling’ of water (a phenomenon of water at the bottom coming-up). This phenomenon is more pronounced on the West Coast.
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But this time upwelling happened on the East Coast and that too during the non-upwelling season. Still CMFRI was not alarmed, since unlike cyclones, tsunami was completely unknown.
Some of the other instances of abnormal behaviour of animals and birds noticed on that fateful day were as under.
i. Crows flew into CMFRI’s fish hatchery in Chennai and didn’t budge.
ii. Cows on the Chennai beach ran like mad away from the coast.
iii. At Point Calimere Wildlife Sanctuary, black bucks and deer fled towards higher ground.
Vegetation:
Impact of tsunamis can be considerably reduced by growing sea coast vegetation. Sea vegetation can be effective protection if the vegetation cover along the coast exceeds 70 per cent of the area. Unfortunately most of the natural vegetation has been destroyed for obtaining fodder and fuel. In Tamil Nadu only 110 km stretch out of a total coastal length of 1,076 km has sufficient vegetation cover.
A team of researchers led by Finn Danielsen of the Nordic Agency for Development and Ecology in Copenhagen, Denmark, presented its findings regarding tsunami damages in Cuddalore district of Tamil Nadu in October, 2005 issue of the journal Science.
According to the report presented by this team, “In the north, stands of mangroves had five associated villages, two on the coast and three behind the mangrove. The villages on the coast were completely destroyed, whereas those behind the mangrove suffered no destruction, even though the waves damaged areas unshielded by vegetation north and south of these villages.” The overall damages were found to be 35 per cent of coastal land without trees, 15 per cent where there were some trees and less than 1 per cent where there was protection by dense tree growth.
Structures like walls, ridges etc. can act as protective devices to some extent. Tamil Nadu government has proposed to construct a sea wall along the entire 1,076 km long coastline from Chennai to Kanniyakumari. But it will have its own financial and ecological limitations.
Although tsunamis constitute a natural tragedy and man has hardly any control on such a powerful natural phenomenon yet man’s own misdeeds have made the situation very dangerous and helped in aggravating the fury of tsunamis.
For example, no construction is allowed within 500 metres of the coast. There is legal obligation in India to leave this stretch of land vacant but all sorts of constructions residential, commercial, recreational etc.) is carried on without caring for the law. People living in this belt are most vulnerable to tsunamis and other sea related hazards.
Mining of sand and other minerals from the sea, as is done in Kanniyakumari, makes the concerned area highly vulnerable to tsunamis. The sand deposited on the sea coast absorbes much energy of the waves, and saves from their fury. There is urgent need to check unwanted construction and mining in ecologically sensitive coastal areas.