Aerial Survey of Mammoth Importance

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The San Diego Zoo collaborates on elephant conservation in Africa with the nonprofit organization Elephants Without Borders, based in Botswana. Read Kelli’s previous post, Wild Elephant Rainbow Spirit.

Elephants are plentiful along the Chobe River.

We are very pleased to share with everyone what has kept Elephants Without Borders (EWB) busy the last few months in the field. With the support of Botswana’s Department of Wildlife & National Parks and the San Diego Zoo Institute for Conservation Research, we finally completed flying a mammoth aerial survey, counting elephants and wildlife species throughout northern Botswana. Piloted by Mike Holding, our 4-member survey team flew the  last 3 months, approximately. 250 hours, in a small, single-engine plane to complete the survey. The distance we covered was about 43,000 kilometers (26, 720 miles), flying along straight transect lines over Botswana’s varied terrain. That amount of flying is longer than the circumference of the Earth at the equator!

The study area essentially encompassed the entire elephant range in northern Botswana of approximately 115,800 square kilometers (44,710 square miles). Over high density wildlife areas, such the Okavango Delta, the sampling coverage was about 22 percent, the highest survey coverage ever flown over a vast area of northern Botswana, making this Botswana’s first aerial survey conducted with such a high sampling intensity. This is important, because the higher the sampling coverage, the more precise the population estimates. (Learn more about aerial surveys.)

An aerial view of zebras in Makgadikgadi.

Wildlife species we counted included large and small herbivores; predators were also noted when seen. Other observations included types of elephant herds (bull or family groups), elephant carcasses, elephant bones, and, if possible, whether tusks were intact or missing. We also recorded observations of selected large birds and nesting sites. Due to the growing concern on what possible impacts elephants are having on large trees in Botswana, and considering baobabs are an iconic tree in the country, we also counted baobab trees and took note of their size and possible damage they may have sustained. We made additional notes on environmental conditions, such as the extent of bush fires and the structural integrity of Botswana’s veterinary fence lines and whether livestock or wildlife had crossed them.

The information on elephant and wildlife numbers, distribution, movements, and demographic characteristics from this study will be incorporated into population models to better understand a variety of research and management questions relating to wildlife ecology and conservation management in Botswana.

This map shows the transects flown for EWB's survey. Click on all images to view in larger format.

We plan to publicize the results of this important aerial survey at an official launch of the report in early January. In addition, we plan to give several presentations on the project results to key stakeholders. The primary objectives of these presentations and meetings will be to share information obtained from this study and from the on-going research activities of EWB, identify priority areas for wildlife corridors, and develop strategies for promoting wildlife conservation in the region. We hope that the results of this collaborative survey with the Department of Wildlife & National Parks will have fundamental conservation management implications for land-use planning and conservation efforts in Botswana.

Kelly Landen is the director/program manager for Elephants Without Borders.

Watch the San Diego Zoo Safari Park’s African elephant herd daily on Elephant Cam.