Small population with nonrestricted habitat

A small population with a more extensive habitat has better prospects for in situ conservation, but may present a real management challenge. Examples of such elephant populations include the Cat Tien National Park in Vietnam, the Mondulkiri-Dak Lac region of Cambodia-Vietnam, and even some regions of West Africa, such as Niokola Koba National Park in Senegal or forest reserves in Togo.

The demographic viability of these populations is still in doubt, but at least these enjoy the luxury of surviving at much below the carrying capacity of the habitat, with prospects for growth. Such populations are less likely to be in conflict with people, but this is not guaranteed.

Some of the management options suggested for small populations with restricted habitats could still be explored, but several other options should be actively pursued. There may be possibilities of supplementing this population with animals from elsewhere. Where space is not a major limitation, the "immigrant" elephants would have better chances of settling down and thereby in creasing the overall demographic and genetic viability of the population. For purely genetic reasons, the introduction of bulls would suffice. This should be carefully monitored to ensure that social conflict among the resident and introduced bulls does not reduce the demographic or even the genetic viability of the population.

The real management challenge, however, lies in nursing the small population to a larger, viable one. There are historical examples of such recovery of elephant populations. A classic example is that of Addo in South Africa. Hunting had reduced the elephant numbers there to an estimated 11 animals in 1931, when a sanctuary was granted. By 1953, when the 117-km park was entirely fenced to keep the elephants inside, the population was under 20 individuals. From here, the population increased at a phenomenal 7% average annual rate to about 325 elephants by the year 2000.

The first goal should be to identify the factor responsible for reducing the population to its present state. In most cases, this would be capture (of Asian elephants) and hunting. Population recovery can be contemplated only when these systematic factors are eliminated (and not just controlled). Intensive management would be needed to aid the recovery process. Dry season mortality of elephants may be reduced through artificial provisioning of water. If the population is nutrient limited, very likely in some habitat types, it may be possible to enrich the habitat with some of these nutrients. Sodium can be provided through artificial salt licks. The suggestion that bore water is enriched with iodine, a nutrient critical for reproduction, is worth investigating. Controlled burns of ground vegetation could stimulate the growth of protein-rich grasses. Obviously, these needs may be locality specific and must be carefully studied before implementation. If the elephants come into conflict with people, it would be necessary to prevent any deaths of either party. If people are killed, there would be demands for removal of elephants or retaliation; the demographic viability of a small population would certainly be compromised if any elephants are eliminated.

The Cat Tien National Park in Vietnam, where I have recently studied the elephants along with Nguyen Xuan Dang and Surendra Varma, is a typical example of this management scenario. Vietnam's wild elephant population is down to as low as 100 or fewer individuals, found scattered in small groups across the country. Cat Tien National Park has remnants of the country's tropical moist forests, with major portions transformed into secondary growth of bamboo and rattan, partly the result of defoliants used by American forces during war. The park itself is divided into two main blocks separated by human settlements; elephants are confined to the southern Nam Cat Tien (383 km2). Our surveys in Cat Tien indicate there may be as few as 9 elephants and at most 12-15 elephants here, a population with very low viability. The presence of two adult bulls and some breeding cows, as evidenced from a juvenile and a newborn within the herd, offers a ray of hope amid the dismal scenario. Nam Cat Tien is bordered to its west and to its south by forestry enterprises with about 280 km2 of secondary forest interspersed with cashew plantations. Thus, about 650 km2 of potential habitat is available for elephants, an area that can easily hold 100 or more elephants. The present small group is largely confined to the southwest of the park, making extensive use of the secondary forests to the south, the cashew trees for their fruit during the dry season, and agricultural fields that are raided beyond.

Saving these elephants by building up the population to a safer level will be a Herculean task; indeed, Cat Tien would be the ultimate test for the survival of the Asian elephant. Our recommendations are to minimize conflict by erecting an electric fence in the southwest, after allowing the elephants the use of part of the enterprise area comprising secondary forest and cashew plantation. The habitat within the park can also be managed in a manner designed to attract elephants. The elephant population itself has to be closely monitored for its demography and health status.

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