Population Viability: Assessing the Impacts of Live Capture on Burma's Wild Elephants
Asian elephants have long taken center stage in people's imagination and fascination. Interactions between people and elephants were recorded in paintings and books as long as 4,000 years ago. Over the centuries, elephants have been valuable allies to people—always to society's advantage, and often leading to the elephants' own demise. Today, people still encounter elephants in many contexts, in the wild, in jungle elephant camps, and in zoos. Despite these close connections, elephants now face almost certain extinction in almost every place they exist in the modern world.
Approximately 15,000 captive Asian elephants—one-third of all living Asian elephants—are found in timber camps, temples, and private camps throughout Asia. Most of them face a dire fate. With reduced revenues in timber operations and declining forest cover, timber elephants increasingly face unemployment. They are condemned to roam the streets, posing with their mahouts to cadge baksheesh from passing tourists.
Myanmar has one of the largest captive populations of Asian elephants. Elephants are the still the most effective tool used in logging, and as many as 3,000 elephants are believed to be kept in government-run logging camps, while an additional 3,000 are privately owned. These captive populations are not self-sustaining, however. For decades they have been supplemented through the capture of live elephants from the wild. Although it has been suggested that this continued live-capture poses a serious threat to Myanmar's remaining wild elephant populations, no one knows what its impact is. However, a recent National Elephant Conservation Workshop in Myanmar indicates that instead of 10,000 remaining wild elephants, there may be fewer than 2,000 elephants remaining in Myanmar's forests. We used population viability modeling to assess how reported rates of wild elephant captures might have contributed to this suspected decline in Myanmar's wild elephant populations.
Modeling Population Dynamics of Captive Elephants
Using birth and death rate data, the survival of the captive elephant population in Myanmar can be predicted over time. Models show that captive populations decline constantly and that current numbers can only be maintained by capturing new elephants on a regular basis. Adding 25 wild elephants per year would still result in a drop from an initial population size of 3,000 to about 1,500, whereas capture of 50 elephants per year would suffice to maintain the original population size over time.
In trying to identify the cause of population instability in the captive herds, wild birth and death rates were inserted into the model. The results of this analysis indicate that improving the birth rate within the captive population could significantly increase survival of that population.
Preliminary models on wild populations suggest that the removal of 50 elephants a year would be devastating, leading to the extinction of a wild elephant population of 2,000 within the next 100 years. Capture of wild elephants in past decades may be the major reason for low population densities of wild elephants in Myanmar.