Yala National Park of southeastern Sri Lanka is a remarkable place of ecological diversity and great natural beauty. Unfortunately, it was situated in the direct path of the catastrophic tsunamis that hit Southeast Asia in December.

Even while the world watched in horror as images of the paths of devastation flickered across television screens, Sri Lankans were called into action to help: first for the humanitarian effort, and soon after, in the case of Wildlife Trust scientist Dr. Prithiviraj "Pruthu" Fernando, to assess the impact of the natural disaster on the ecosystems of Yala National Park. Pruthu and his associates' assessment and study of the tsunami impact in Yala began on January 1 and is on-going.

For his current research, Pruthu is partnering with Jennifer Pastorini, Devaka Weerakoon and Eric Wikramanayake through the Centre for Conservation and Research (CCR) to study a 30-mile section of coastline, from Palatupana to Okanda. While parts of the coastline were protected by coastal sand dunes, sea incursion onto land occurred through lagoon inlets, estuaries and areas not protected by dunes.

The ground team is mapping the area of impact, and assessing the effects on vegetation, fresh water bodies and fauna, with observational date collection on beach line, dune height, extent of flooding and type of damage, etc.

In this WT online interview,
Pruthu discusses his work.

1. Where were you when you heard about the tsunami?

We were in Colombo, back from fieldwork in Yala where we collared a second elephant as part of our elephant conservation work with the Dept. of Wildlife Conservation. We, like all other Sri Lankans, only heard of the tsunami after it hit the shores of Sri Lanka. At first, we thought it was a minor event, but then the pictures of the destruction made it clear that this was indeed a catastrophe of great magnitude, and the death toll kept mounting and mounting with every hour, making this the largest human disaster Sri Lanka has experienced. The TV stations immediately started sending out appeals for help and practically all Sri Lankans immediately responded by bringing clothes, food, water, etc. to the collection centres.

2. As a scientist, what were your first thoughts when you heard the news?

I am afraid I only started thinking as a scientist a few days after the event. It was such a massive humanitarian catastrophe of unprecedented scale that all our thoughts and actions over the first few days were about what could be done for the survivors. We, like thousands of other Sri Lankans, provided what assistance we could for the people effected and went round helping with medical camps, etc.

Then one of the trustees of CCR called and said that they had a large consignment of medicine, so we decided to take them to the area close to Yala and distribute them, because supplies were still not getting there. Once the humanitarian issues were getting under control with the government and aid organizations stepping in, we began thinking more about what the tsunami would mean in environmental terms.

3. You know Yala National Park very well. What makes this park such a remarkable place?

Yala is the largest protected area complex in Sri Lanka being over 1500 square km, and especially in terms of elephant conservation, it's one of the most important. It is also interesting because of the diversity of habitat types. Being situated on the southeastern corner of Sri Lanka, it has a coast that stretches almost 60 km, completely uninhabited, with pristine beaches and some really amazing areas of sand dunes, limestone cliffs, etc.

Then there are the lagoons, the fresh water lakes, dry thorn forest, scrub forest, the gallery forests along the rivers, and more inland: the evergreen monsoon forests. A number of rock outcrops and isolated granite masses occur across the landscape. A number of prehistoric and historic sites also occur within the Yala National Park.

It is also a great place to observe the large mammals of Sri Lanka such as elephants, leopards, sloth bear, sambur, spotted deer, wild boar, etc., as well as a multitude of birds both resident and migrant.

So it is almost an entire world, where one could spend a few life times and still be surprised by something new the next day!

4. How long have you worked on research projects in Yala? What's the nature of those projects?

I started my thesis work in Yala in 1992 and have been working there since then. The first work I did was based on radio tracking five elephants, for which we spent long hours tracking them from dawn to dusk, day in and day out. They wandered over a large area of the park and we followed them. We spent many hours collecting observational data to identify individuals, study social organization, feeding ecology etc.

We became very familiar with the landscape and the fauna and flora of Yala during this time. This work formed the basis of my research, which has continued since then. Even through the time I was writing up my thesis work at the University of Oregon, and my subsequent work at Columbia University in New York, I kept the project going and spent a few months every year in Sri Lanka.

Since 2004, I decided to be based back in Sri Lanka and have spent most of my time working in Yala.

5. What were your first impressions as you walked through Yala National Park, after the tsunami hit?

The first impressions were of the enormous scale of the impact. One could see a huge area where practically every single tree was broken or uprooted and the vegetation rolled into massive tangled clumps, all of which appeared to be dead. When you are standing in the middle of a patch one square mile, which has been devastated in this manner, with trees over two to three feet in diameter broken in two as if they were match sticks, others torn from their roots and transported many hundreds of yards, sweeping all that was around into tangled masses, one can but wonder at the immense force that was unleashed.

We also visited areas of short grass fields, which were inundated. Here all the grasses and herbs were dead and looked as if it was the height of the dry season rather than the end of the wet season, when everything should have been lush and green.

However, we also noted that where there was a sand dune 20 feet high, there was practically no damage and the force of the wave was absorbed by the dune and incursion of water into the land prevented. So the damage appeared to be severe where it occurred, but patchy in nature, with incursions only occurring at the deepest point of curvature of bays.

6. What do you hope to accomplish through your current research to assess the impact of the tsunami on natural eco-systems of Yala National Park?

One way of looking at the tsunamis is that it is something that has not happened in living memory and that it is an unprecedented event.

While this is true from the point of view of the human toll, if one looks at it from an evolutionary point of view, one is looking at an entirely different time scale and tsunamis are not that rare. In fact the last tsunami recorded in Sri Lanka was caused by the cataclysmic eruption of the volcano Krakatoa in 1883. While very few people were killed, the tsunamis that were caused were likely of similar magnitude.

Then again, there are records of a massive tsunami in the 1500s when the coastal areas of Sri Lanka were under Portuguese rule. So tsunamis occur in this part of the world with a periodicity of a few hundred years.

At first sight, everything in the areas impacted appeared to be dead, and we expected a process of primary succession to occur. However, no one had done a scientific study of how a natural tropical eco system responds to a tsunami. After all, the last time a tsunami occurred in this region, science was still in its infancy.

Therefore, we decided that this was an opportunity where we could actually undertake a scientific study of a phenomenon that could have a profound effect on shaping coastal eco-systems. Contrary to expectations, we were amazed to see that practically everything that had a root left in the ground started regenerating. The grasses that appeared dead and brown put out new green shoots, the sea shore vegetation that was buried under a foot of sand sent out shoots to the surface.... so it seemed that most of the vegetation did survive, and the recovery process would be one of regeneration rather than succession.

Thus, if most individuals did survive and some did not, obviously some would survive better than others. In other words, natural selection could indeed be exerting a strong effect here.

Similar profound effects could also be occurring with respect to the fauna. In the areas inundated, practically all land snails appeared to be wiped out; so too with the frogs in the fresh water bodies inundated.

We want to look at these things in more detail, and answer questions such as:

•  What are the inshore and offshore physical factors that determine the impact of a tsunami on a location?

•  What are the species impacted and to what extent?

•  How will the flora and fauna respond to the tsunami?

Therefore, our approach has been first to document the impact of the tsunami, monitor the process of recovery, and conduct detailed studies so that we can understand the role of such catastrophes in shaping nature.