Large population with restricted habitat

A large population close to the carrying capacity of the habitat, without scope for expansion of its range, presents several management dilemmas. The elephants could be rapidly transforming their habitat, as in parts of semiarid Africa, or they could be in serious conflict with agriculture. Examples include the Nilgiris-Biligirirangans region in southern India and several populations in southern Africa. Management of such populations should not encourage further growth through habitat manipulation, but rather aim at stabilizing elephant numbers. I am stating this explicitly because there is often a tendency in wildlife management practice to manipulate the habitat excessively without a clear understanding of its long-term consequences for animal populations. For instance, the density of an elephant population, normally determined by vegetation, may be artificially increased through provisioning of water. Within the elephant's range in southern India, water is impounded not only in small ponds, but also by a large number of dams, with a spread of 5-150 km2. Water is therefore not a limiting factor; it may actually be excessively available in many parks. This may have lowered dry season mortality, resulting in strong population growth and artificially high densities in places. I mentioned the experience of Kruger in South Africa, where provisioning of water could have influenced the strong population growth.

Abundant populations may be at risk of a crash during periods of serious drought. Such populations are also in conflict with peopleā€”a headache for park management. Over the long term, it would be impractical and expensive to prop up an abundant population through artificial means. Therefore, the goal of management should be to allow larger elephant populations to regulate themselves at "natural" densities. The point I wish to emphasize here is that field management of large wildlife populations should allow the evolutionary process to operate with minimal interference. A large population has the luxury of being able to absorb normal environmental fluctuations. Some additional dry season mortality may not be a bad thing; in the medium to long term, this would help stabilize an abundant elephant population apart from ensuring the "survival of the fittest."

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