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![]() Determining the Status of PopulationsThe African Elephant Database, which is maintained by AfESG in collaboration with UNEP, collects, compiles, and disseminates information on elephant numbers and distribution. The value of the database, however, can be no better than the quality of the data entered into it, which varies in quality from the definitive to the speculative. The data for a third of the range states is comprised from guesswork. Elephant populations can be counted by total, or sample, aerial surveys; by total ground counts of known animals, or by dung counts. Because of forest and cloud cover, aerial surveys tend to underestimate the true number of elephants by unknown amounts. W hile dung counts can provide estimates of elephant numbers, there is room for improvement in both accuracy and cost-effectiveness. Extrapolation from local density figures to determining the size of an elephant population in an entire region can be improv ed when more detailed information on elephant distribution and on the relationship between elephant density and forest habitats is known. Thus the shortcomings of the present survey situation. Relatively few elephant populations have, in fact, been properly surveyed, largely due to limitations of both finance and capacity. Generally speaking, there is good information from savanna populations in some eastern and southern African countries that have regular aerial survey programmes and at least some cooperation in the surveying of cross-border populations. Little information, however, is available from Sudan, Somalia, Mozambique, and Angola, and the savanna populations of central and western Afr ica. The coverage of forest elephants is much less complete, because of the great difficulty, high cost, and the expertise that is needed in conducting dung counts.
Tracking the movements of herds that cross international borders, or move great distances within a country, present particular problems for conservation and management. Some information will come from surveys, but the most effective technique is through t he use of radio telemetry. Yet this approach requires considerable effort and expense to organize, and is of limited use in forest habitats. It is hoped that advances in the use of satellites and remote-tracking technology will make the study of movements easier, although it may not necessarily become cheaper. As financial and hence human and technical resources are always less than the study and management of elephants throughout their range requires, it may be necessary to concentrate conservation action on priority populations. There are various different wa ys in which this can be done. For example, building on the conservation biology tenet of "minimum viable populations", priorities could be set on the basis of the assumed viability, size (e.g. those > 5,000), and/or ecological uniqueness of selected popul ations, including special adaptations to specific types of habitats. In future, other criteria for prioritisation, derived from the conclusions of current studies of the genetic differences between forest and savanna elephants may be established. For the present, there is no consensus among conservation and management specialists on how priority populations should be determined. Next: Building Capacity for Elephant Conservation and Management
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