A line transect dung count was conducted in the Rio Muni region of Equatorial Guinea in 2011. The survey gave an elephant population estimate of 884 (437-1,789). Dung decay rates were estimated on-site following the retrospective method recommended by Laing et al (2003). The elephant dung density was calculated internally using the Barnes & Jensen (1987) formula (E = Yr/D, where E = elephant density, Y = dung density and r = dung decay rate which is 1/t where t = number of days to decay).
Source:Murai, M., Ruffler, H., Berlemont, A., Campbell, G., Esono, F., Agbor, A., Mbomio, D., Ebana, A., Nze, A. and Kuhl, H.S. (2013). 'Priority Areas for Large Mammal Conservation in Equatorial Guinea'. PLoS ONE 8(9), p.e75024.