Megaparks for metapopulations: Addressing the causes of locally high elephant numbers in southern Africa

Abstract

Conservation management options for southern African elephants range from local to regional scales. Here we review these options and argue in favour of actions that will deal with the causes rather than symptoms of elephant numbers that are locally high. Metapopulation theory ensures population persistence, while our approach extends this in order to stabilise elephant numbers regionally. By allowing for the development and maintenance of regional sinks, we may also limit numbers in sources. This application of the metapopulation metaphor is a powerful ecological platform from which to manage elephant numbers and impact through southern Africa. Our approach engages the causes of the apparently high abundance of elephants in parts of southern Africa. It moves away from the practice of dealing only with numbers (symptoms) when managing the impact of elephants on other species. While providing an ecological basis for the development of elephant management options, this needs to be melded with social, political and economic realities through southern Africa. In this regard we are encouraged by the ongoing development of several Transfrontier Conservation programmes and Peace Parks across the region. Article Outline

Incorporating mortality into habitat selection to identify secure and risky habitats for savannah elephants

“…Understanding the possible habitat variables which could contribute to mortality is the first step towards developing a habitat-based management plan. Balancing factors that contribute to elephant fitness and mortality to stabilize growth is a management option that could help alleviate concerns of elephant overpopulation (van Aarde and Jackson, 2007). Past elephant management entailed fencing populations into protected parks and supplementing water, which often resulted in localized overpopulation (van Aarde and Jackson, 2007).…”

“…Across Africa, initiatives to create corridors, link protected areas, and establish transfrontier conservation areas may increase the amount of land available to elephants. By increasing connectivity between protected areas we may be able to support and maintain the natural regulatory processes, such as long distance migrations and habitat heterogeneity, which may have help to limit elephant populations in the past (van Aarde and Jackson, 2007).…”

“…Habitat heterogeneity contributes to the spatial pattern of use and mortalities of elephants, and describing those patterns in particularly important in Africa, where the management of savanna elephants is a continuing concern (van Aarde and Jackson, 2007). Hunting and poaching in the late 19 th and early to mid 20 th century reduced some populations to near extinction (Roth and Douglas-Hamilton, 1991;Whyte et al, 2003), but actions taken to decrease poaching in the mid to late-20 th century were largely successful in southern Africa (Whyte et al, 2003).…”

Fecal 20-oxo-pregnane concentrations in free-ranging African elephants (Loxodonta africana) treated with porcine zona pellucida vaccine

“…Currently, various approaches have been explored in regards to managing elephant numbers, all with different advantages and disadvantages, including culling [5,6], translocation [5,7], range expansion [5,7,8], sterilization [9,10] and contraception [10,11]. In this regard, the use of the porcine zona pellucida (pZP) vaccine for immunocontraception of African elephant cows is a fairly recent development.…”

Functional connectivity within conservation networks: Delineating corridors for African elephants

“…Historically, the world's biodiversity was preserved through the establishment of parks and protected areas, but current initiatives are moving towards increasing connectivity between these wildlife islands (Hanks 2001;van Aarde and Jackson 2007). The establishment of transfrontier conservation areas (TFCA) and corridors interconnecting multiple protected areas, such as the Kavango-Zambezi TFCA in southern Africa and the Yellowstone to Yukon Corridor in the North America, are an increasing trend.…”