The Bukit Tigapuluh Project

In the Bukit Tigapuluh forest, Sumatra (Indonesia), more than 8,000 people live in the immediate vicinity of elephants. Over the last years an increasing number of serious incidents has been recorded in which elephants have entered small settlements, destroyed homes and even killed and injured people.

Against this background it is likely that human-elephant conflicts (HEC) will escalate in the near future, if nothing changes.

Crop raiding occurs frequently, and as a result elephants have been killed by poison set out by upset locals. The Bukit Tigapuluh elephants live almost exclusively outside protected areas and have to share much of their shrinking habitat with a growing number of people. If nothing is done to curb these negative interactions it is likely that human elephant conflict (HEC) will escalate in the near future as the human population continues to swell.

The objectives of this project are to:

  1. develop and test site-specific conflict mitigation techniques and strategies, and
  2. promote and support their implementation.

As the long-term goal of the project is to create a situation in which elephants and people are able to coexist in a peaceful manner, the cooperation of stakeholders (e.g. local people, authorities, concession managers) will be of high priority in all of the project’s stages.

The project is decreasing serious HEC incidents (e.g. killing of elephants and human injuries/deaths) and crop raiding.

As the Bukit Tigapuluh elephants form one of only two populations with long-term survival potential in central Sumatra, a decrease of HEC in Bukit Tigapuluh will improve the overall chances of survival for this subspecies.

Invisible Giants in the Thicket

Despite their size, Sumatran elephants are not easy to see. As the animals live hidden in jungle thickets, biologists have to make do with indirect indications and interpreting their tracks.

Time and again, people are amazed at how difficult it is to count wild elephants. You might think that a mammal of this size would be easy to spot. But unfortunately that is not the case. On the contrary, the precise estimation of the size of a wild elephant population is a real challenge for the biologists of the ECMU in Sumatra. As Sumatran elephants can only rarely be observed in their natural habitat (and when they are, then generally only under circumstances which do not permit direct counting), we have to use more sophisticated methods.

Tracking the Elephants with DNA Samples

Whenever animals cannot be counted directly, biologists avail of indirect indications of the presence of the animals and then apply scientific methods and statistical models to analyse these indirect observations and ‘convert’ them into individual or population sizes. Indicators which have proven particularly helpful here are animal gnaw marks, footprints, sounds and, above all, droppings. On average, an elephant produces a well-sized dung heap 18 times a day, which is not only relatively easy to find, but also holds much more information than one might think. The outer layer of elephant dung, in particular, contains epithelia cells, which are ‘scraped off’ as course fodder passes through the intestines. These cells contain the elephant’s DNA. Using highly-sensitive forensic methods, these can be extracted in specially-equipped laboratories and conserved. Once the animal’s DNA has been secured, a so-called genetic fingerprint can be taken, allowing the almost certain identification of an individual elephant. When enough dung samples have been collected and analysed, the minimum number of animals in an area can be determined exactly, and the total population estimated precisely.

The ECMU in Indonesia is among the first projects worldwide to use this new technique for calculating elephant numbers. The project’s field work in Bukit Tigapuluh has already been completed, the dung samples collected are currently being analysed in cooperation with the Berlin Leibniz Institute for Zoo and Wildlife Research and the Eijkman Institute for Molecular Biology in Jakarta (Indonesia). First results are expected for around the end of 2012.

The question still remains: what is the point of all these endeavours? Do we really need to know how many elephants are living in a particular area? Of course the fact that they are being counted is of little immediate help to the elephants. However, population studies provide nature conservation authorities and wildlife managers with important key data for conserving animals, for example, when it comes to negotiating sufficiently-large conservation areas, evaluating species conservation programmes or designing management plans. Meaningful work in the area of nature conservation cannot be based on assumption; it needs solid facts. With our DNA study, we can not only estimate the population size but also recognise population fluctuation, document the distribution of the animals and monitor the gender ratio and the age structure of the population. In this way, we can identify negative effects on the population, e.g. through farming and forestry, in good time and are able to take countermeasures.

Direct Monitoring using GPS Transmitters

A broad back pushes its way through dense undergrowth, barely making a sound. A few moments later, Anna is standing in the clearing. The last rays of sunlight fall gently on her skin, dark in colour after her evening bath. The rest of the family follows at an easy pace, taking its time. The whole day long, there was barely any indication of their presence. Only now, as evening falls, does Anna’s family leave the small area of forest in which it has spent the day. Anna is the first of a total of five elephants we equipped with radio transmitters in early August 2012, in cooperation with the Indonesian Elephant specialist Pak Nazaruddin and the German vet Christopher Stremme (Veterinary Society for Sumatran Wildlife Conservation, VESSWIC) within the framework of the Elephant Protection Programme. Around her neck, Anna is wearing a small transmitter which determines her position every four hours via GPS and relays it in real time to a computer network. In addition to a GPS transmitter, the elephant’s collar also contains a VHF transmitter which allows the animal to be located precisely over short distances by classic radio telemetry. Only using this technology is it possible to meaningfully follow the animals’ movements and gain deeper insights into their behaviour. Despite their size, Sumatran elephants are true masters of camouflage and rarely allow themselves to be observed under normal conditions.

As the majority of the elephants in Sumatra are increasingly finding themselves in conflict with the local population, most of the encounters between humans and elephants are of a negative nature – making the animals even more timid and cautious. Elephants are adaptable and have learned to help themselves from fields and plantations, generally under cover of darkness, when the farmers are not working their land. The fact that elephants that come across cultivated crops in their habitat dine on them, is hardly surprising – conflicts with the farmers are just waiting to happen. This turns the elephants into “problem animals” that are often combated using all available means. Anna and her family are so-called problem elephants, animals that, because of the destruction of their habitat, have come into conflict with the land-hungry population.

This is where the new transmitter comes in, allowing the elephants’ movements to be tracked. When a group approaches a village, the farmers can be warned and patrols activated to prevent the elephants encroaching into the agricultural areas - before the animals can cause major damage. This early warning system is now being tested within the framework of the Human Elephant Conflict Mitigation project and is intended to significantly augment the activities of the ECMU team. If it is possible to minimise the damage to plantations, the likelihood of farmers poisoning or injuring elephants will sink. Furthermore, with the help of the transmission collars, it is possible to follow the elephants in their habitat. The presence of the ECMU in close proximity to the animals make is increasingly difficult for poachers and intractable farmers to kill an elephant. The use of this technology therefore benefits both humans and the elephants and could prove a very effective method for elephant conservation in the future, not only in Bukit Tigapuluh.