Story Of The Month

So how did the wildlife survive?

  Contd. From our last issue.

  -Gehan de Silva Wijeyeratne, CEO, Jetwing Eco Holidays (www.jetwingeco.com)

  Sixth senses aside, one simple reason why animals survived is that the few hundred meters beside the coastline is an arid habitat. It is generally sparsely populated by large, visible animals, relative to the habitats further inland which has fresh water pools and grassy meadows fringed by scrub of woodland.

Another reason could be the so called sixth sense which allowed many animals to 'hear' the arrival of the Tsunami. The seismic activity which generated the Tsunami would have generated energy waves at long wavelengths. Long wavelengths carry great distances, which is why radio communication uses long wavelengths. The human ear hears within the range of 20 - 20,000 Hz. Many animals have a wider auditory or hearing range.Elephants have been studied for a number of years on their use of communication with infra sounds, wavelengths longer than which the human ear is able to hear. They are also known to stomp their feet and create seismic waves which can be picked up by other elephants over 40 km away. In November 2003, I remember being in Yala with Lyn Hughes, the Managing Editor of Wanderlust Magazine. A distressed family of elephants touched and nuzzled each other whilst keeping up a chorus of deep rumbles. I also guessed they were communicating in infrasound, with other members of the family. Mature bulls are usually solitary, but one bull may have been tailing the family because one of the cows were in heat. Suddenly there was a crash in the undergrowth and a big tusker emerged 'stomping' his feet, sending seismic waves announcing his arrival and might.

In "Leopard and other wildlife of Yala, Charles Santiapillai et al write "The feet of elephants are filled with vibration sensors known as Pacinian corpuscles, which have a structure similar to an onion, with a shiny gel between each layer. Vibrations from the ground are picked up by the feet and passed on to the brain through these sensors. Thus, they are able to detect infra sound which we cannot hear, and communicate over very large distances".

The so called sixth sense is probably in many cases a wider hearing range which allowed them to pick up wavelengths which the humans did not hear. In a sense they heard the arrival of the Tsunami. This could have been airborne infra sounds or seismic waves (also in the infra sound range). Even noise audible to humans would have been detected earlier by animals who have more sensitive hearing. A few seconds or minutes of extra warning would have given them enough time scramble to safety. Sometimes all that was need was to climb a tall tree or flee a few hundred meters.

Animals such as lizards and snakes who are sensitive to vibrations may also have picked up tremors as the Tsunami approached the shore. Nadeera Weerasinghe, one of the naturalists of the Yala Safari Game Lodge reported seeingsnakes and lizards sharing the trees which human survivors had climbed.

Birds which migrate long distances and turtles have a sophisticated mechanism for detecting subtle changes in the earth's geomagnetism. Seismic activity could produce changes which animals can detect. But it is unlikely that birds in Sri Lanka were alerted by geo-magnetic changes. As the tidal wave struck the east and south coast, oblivious to it, I was in the Kotte Marshes, a wetland on the outskirts of Colombo . A flock of over 100Lesser Sand Plovers and Golden Plovers , winter migrants gave no hint of impending devastation.Purple Swamphens were engaged in bitter territorial warnings. There was no hint of danger from the wildlife around me.

It seems that the birds in Sri Lanka picked up the danger, visually by seeing the tidal wave and not by geo-magnetic changes or changes in atmospheric pressure.

Uditha Hettige in his account of survival e-mailed to me wrote "In the morning, about 20-30 minutes before the tsunami hit Yala, I saw flocks of birds (Black-headed Ibis, Painted Storks, Openbill Storks , etc) flying inland. That does not prove that they sensed the tsunami. I have seen them behaving like this before due to other reasons.

I was at Yala at the time the tsunami hit the Yala area. I was having breakfast at that time, while looking at the lagoon. A group of birds (Cormorants, Egrets, Terns , etc.) took off suddenly and I knew that it was not because of an attack by an animal (e.g. raptor or bird of prey). At the same time I looked at the estuary of the lagoon and saw water coming from the estuary of the lagoon. And at that point it occurred to me for water to come this far, it must be a tidal wave as the beach is about 100m away and 5 feet plus lower than the level of the hotel. I could not see the sea because my view was blocked by a row of rooms. I stood up, even without grabbing my camera bag and shouted “Tidal Wave” and started running and everybody around started running".

The birds probably picked up an acute alarm call from birds in the air. Birds have a varied vocal repertoire which serve different purposes. In the rainforests of Sri Lanka , one can hear the Sri LankaCrested Drongo uttering a 'flock gathering' call to form a mixed species feeding flock. I have heard the same bird utter an alarm call and observed how the whole forest falls silent as animals freeze for safety. Uditha's account supports the view that many of the birds escaped by other birds raising the alarm after visual detection. Perhaps Sri Lanka was too far from the center of seismic activity for geo-magnetism to have played a part.

On the 28th of December, I noticed one of the Giant Squirrelsat the Game Lodge back in its old territory. The sounders of wild pigwere back. Animal life had returned to normal. For us humans, we will forever be scarred by the tragedy of the great wave which swept away many lives. We still have hope and determination to re-build a shattered nation. Recognizing the need to help the local communities who are dependent on wildlife tourism and because the damage was minimal, the park was officially re-opened on 5 January 2005 . Wildlife conservationists and animal lovers can help the local communities by travelling to Sri Lanka 's national parks and reserves. The park is ready for visitors and so are all of the places providing accommodation at Tissa (and the Yala Village hotel). Everyone from safari jeep drivers, to wayside kiosk owners to room boys and restaurant waiters, need the dignity of employment to face the future. Many tour operators and clients have responded positively and confirmed their travel plans from mid January onwards.




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