This report documents an aerial survey of the Zambezi landscape in north-east Namibia conducted in September-October 2015.
The survey was conducted using a Cessna 182 to cover the 17 474 km² area at an average intensity of 13%. A total elephant population of 13 136 (95% c.i. 9 701 - 16 570) was estimated across 8 strata. The stratification of the survey area was based of the distribution of elephants seen during the 2011 dry season survey (MET 2011).
The number of elephants estimated has decreased since the 2014 survey (13 136 as opposed to 14 095), although the change is not statistically significant. However, the report notes that there has has been a very highly significant increase in the estimated number of elephant carcasses since 2014. Other observations suggest that illegal hunting of elephants continues to take place in the area.
The elephant carcass ratio (8%) is assessed to represent mortality rates on the margin of sustainability.
The authors note that the Salambala-Impalila stratum, where carcasses unexpectedly increased tenfold, should have been sampled at the same level as the previous survey for best precision. In addition, one observer consistently identified more carcasses than the other, which may suggest an underestimate in carcass numbers overall.
Source:Gibson, D. S. C., & Craig, G. C. (2015b). Aerial Survey of Elephants and Other Wildlife in Zambezi Region September/October 2015. WWF.