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In 1995, Mek Penawar became the first Asian elephant to be equipped with a satellite tracking transmitter. Mek Penawar had been relocated after she raided a starfruit plantation in southern Malaysia. The satellite transmitter was used to monitor her post-release movements.

In 1996, male tusker Abang Ramadan, became the project's second elephant. Abang Ramadan also had been relocated after raiding crops on a plantation in southern Malaysia. He was released at the same site as Mek Penawar

The Malaysian Elephant Satellite Tracking Project is a collaboration of the Department of Wildlife and National Parks Peninsular Malaysia and the Smithsonian Institution Conservation and Research Center.

The Malaysian Wildlife Department's (DWNP) helps landowners reduce crop damage caused by wildlife. Because elephants can cause great damage to plantations, DWNP has an elephant relocation program. Elephants are identified as repeated crop raiders are moved from agricultural to protected areas.

Mek Penawar had been captured in a fruit tree plantation in Peninsular Malaysia's most southern state of Johore. She was trucked about 250 miles north and released in Taman Negara National Park. Mek Penawar was one of more than 400 elephants captured and relocated by DWNP from 1974.

The goal of the satellite tracking project was to learn where elephants went after they were released in Taman Negara National Park. Researchers wondered if the reloacted elephants stay near the release site, go back to where they were caught, or randomly move about until they establish themselves at a specific site. They also wondered how fast the elephants moved.

Earlier tracking difficulties

Previous attempts to follow the movements of elephants released in Taman Negara using regular ground tracking telemetry had been unsuccessful. The hilly terrain and dense rain forest had made it very difficult for persons on the ground to receive signals from the tracking transmitters.

For the satellite tracking project, the scientists attached a transmitter to Mek Penawar. It beamed radio signals to satellites passing overhead. The satellites relayed data to stations elsewhere on Earth where computers calculated Mek's location. Thatlocation information was then sent to the computers of the home researchers who then plotted Mek's movements.

Mek's satellite transmitter was a little white box attached to a collar made of heavy machine belting.

Tracking animals on the ground

It is difficult to follow the movements of wild animals without modern electronic tools. Many wild animals move around at night. They often move through terrain that is hard for humans to penetrate.

Radiotelemetry is a tool that has been used successfully to track animal movements. To use that tool, an animal is caught, a transmitter is attached -- usually around the neck -- and the animal is released. The signal strnegth of the transmitter then is received by a directional antenna from a distance of up to a few miles.

The researcher receives several signal readings at about the same time from different locations. This allows a reasonably accurate calculation of where the animal is -- the spot from which the signal was sent.

Most radio tracking still is done by humans on the ground. However, since the researcher has to be near an anaimal to receivbe the radio signal, certain kinds of animals moving about in remote or difficult locations have been trakced more readily by airplanes. Also, if several animals are being tracked in a large area, airplanes are handy.

Satellites are even more useful

The area in which the researchers released the elephant Mek Penawar was very hilly and covered with dense jungle. Signals from the telemetry transmitters did not travel far through the jungle as they were reflected by the trees. Signals became garbled as they crossed from one valley into the next because they were reflected by the hillsides.

Trackers constantly had to climb hilltops to receive signals at all. There was no road network that the trackers might have used to move to strategic reception points to locate the elephants.

Twice they tracked an elephant by helicopter, using the ground-tracking equipment. That was successful. However, regular tracking of elephants by aircraft was not feasible. There were only a few small aircraft in Malaysia and the cost of hiring aircraft was prohibitive. Thus, the researchers were prompted us to use satellite telemetry.

ARGOS satellites

The U.S. National Oceanographic and Atmospheric Administration (NOAA) weather satellites circled the earth at about 500 miles altitude. Several NOAA satellites had ARGOS instruments inside. Those instruments could detect signals from the low-power transmitters carried by the elephants when the satellites were overhead.

When a satellite would receive two data messages during one overhead pass, computers at the Earth station could calculate the location of the transmitter -- where the elephant was. Location computations with greatest accuracy were based on four or more data messages. In that instance, there was a good chance that the elephant being tracked actually was within one kilometer of the location calculated by the satellite.

Satellites have problems, too

The researchers had three problems with the satellite telemetry:

The elephants were released close to the equator at about 4 degrees Northern latitude. Two NOAA satellites with ARGOS instruments passed over that area eight or nine times a day. Each pass lasted between two and twelve minutes, depending on the location of the satellite in relation to the transmitter. As a result, the researchers had only eight or nine short windows of opportunity each day to get a location for the elephants.

The jungle around the elephant release area was very dense. The tree canopy was closed overhead. In many places, the low-power signal of the satellite transmitter attached to the elephant was not able to penetrate upward through the canopy. If the elephant was standing under dense canopy during the eight or nine short passes, the researchers might not get a single location report for an entire day. Of course, they tested the transmitters in the release area before they put them on elephants. They even tied them to branches under canopies of different density to see whether signals could get through. Unfortunately, the results were not encouraging. It turned out that only one out of three signals got through to the satellite. Still, they decided to go ahead and attach the transmitters to the elephants. They hoped that the elephants would go to streams and lakes to drink and bathe. Since bodies of water would not have a closed tree canopy overhead, the radio signal could reach one of the satellites.

Satellite telemetry also was very expensive. Daily tracking of one transmitter cost the equivalent of some U.S.$3700 per year. ARGOS did offer a reduced-price tracking plan at about one third of the cost. However, that plan allows the transmitter to be turned on only one third of the time. If the satellite were to pass overhead at a time when the transmitter was not sending a signal, no location would be calculated, and the elephant would be lost for a time. Fulltime tracking was thought to be important.

How did it turn out?

Satellite telemetry probably was the only way to follow the relocated elephants. For instance, during the first twelve months of tracking, Mek Penawar moved long distances within a range of almost 4,500 miles. That large a range would have made it impossible to track her from the ground. Searching such a large area by aircraft would have been prohibitively expensive.

SOURCES: Centre National d'Etudes Spatiales (CNES, the French space agency), National Aeronautics and Space Administration (NASA) and the National Oceanic and Atmospheric Administration (NOAA), the National Zoo's Office of Public Affairs, Smithsonian Institution Office of Information Resource Management, Spatial Analysis Laboratory at the University of Vermont School of Natural Resources, and Space Satellite Handbook.

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