Survey Methods | How Many? | Aerial Surveys: Advantages

A map of Africa that shows the aerial survey area for the Zambezi Valley in north Zimbabwe with layers that can be selected to show the area of the Strata, Blocks, Transects, and Flight Paths.

The Strata map layer shows a large survey area on the left and a smaller one below it to the right. The larger survey area is divided into 24 different irregularly shaped strata. The smaller survey area is divided into three different irregularly shaped strata.

The Blocks map layer shows a roughly circular area of irregularly shaped and spaced blocks on the left-hand side. From there, a scattering of blocks appears going diagonally to the upper right and diagonally to the lower left. A separate cluster of six blocks appears on the right-hand side of the map.

The Transects map layer shows a roughly triangular area on the left-hand side of the map with closely spaced horizontal lines. To the right of it is a roughly trapezoidal area with vertical lines that are even more closely spaced than those in the area to the left. These closely spaced vertical lines continue in a roughly finger-shaped area extending to the right from the top of the trapezoid. Below this area is an area with closely spaced horizontal lines at the top with three more widely spaced lines in the middle and more closely spaced lines below it. Areas with increasingly widely spaced horizontal lines extend beyond it to the right-hand side of the map. Above this area of horizontal lines is an area with widely spaced vertical lines. Above this area of vertical lines is an area of widely spaced horizontal lines.

The Flight Paths map layer shows a roughly triangular area on the left-hand side of the map with closely spaced horizontal lines. To the right of it is a roughly trapezoidal area with vertical lines that are even more closely spaced than those in the area to the left. These closely spaced vertical lines continue in a roughly finger-shaped area extending to the right from the top of the trapezoid. Below this area is an area with closely spaced horizontal lines at the top with three more widely spaced lines in the middle and more closely spaced lines below it. Areas with increasingly widely spaced horizontal lines extend beyond it to the right-hand side of the map. Above this area of horizontal lines is an area with widely spaced vertical lines. Above this area of vertical lines is an area of even more widely spaced horizontal lines. Clustered areas with higher concentrations of intersecting lines appear on the lower left-hand side of the map extending diagonally to the top right and horizontally to the right. A separate area with clusters of higher concentrations of intersecting lines appears at the lower right.

Expand/Collapse

Aerial Surveys

Aerial surveys are the most common method for directly counting large numbers of savanna elephants spread across vast landscapes. Because of their large size, elephants in open habitats are easy to identify from aircrafts or helicopters. Aerial surveys also allow researchers to census areas that are inaccessible on the ground. An aerial survey costs about 25% of what a dung survey covering the same area would cost.

The map shows the survey area for the Zambezi Valley in Zimbabwe, with transect sample counts in strata with flat terrain and block sample counts in strata with hilly terrain. The total count method was not used in this survey area.

Suggestions for viewing the map:

Select the flight paths layer to see the actual path that the airplane flew during the survey. To best view the block and transect layers, unselect the flight paths layer.