Population Survey

The forest elephant (Loxodonta africana cyclotis) is a keystone species in the rainforest ecosystems of the Congo basin. In March 2014 an elephant survey from dung pile encounters was conducted in the Lomako Yokokala Faunal Reserve, northern Democratic Republic of Congo. Before 2010, no elephant signs had been detected in the reserve. The aims of the survey were to estimate baseline elephant abundance through dung encounter rates and to examine if the population was breeding. The survey yielded 49 dung encounters, leading to wide confidence intervals when conventional methods were used to estimate elephant abundance. Consequently two methods of analysis of transect and reconnaissance (recce) data were used, namely: Adapted Jolly’s 1969 aerial survey, and recce methods were used. Results from Jolly’s method suggested that there were 0.09 (95% CI: 0.0905-0.0907) elephants.km-2 translating to 105 (95% CI: 65-145) elephants in the area. The recce method suggested that there were 0.0002 (95% CI: 0) elephants.km-2 translating to < 1.0 elephants. Camera-traps captured images of at least two cows and a calf suggesting that the population is breeding. Restoring the elephant population and encouraging its growth in the reserve and neighbouring forests are key for optimal ecosystem performance in the area. Elephant density (Jolly method) estimated as 0.09 (95% c.l. 0.0905-0.0907) Survey type (Line transect, guided recce, or travel recce); "Jolly's 1969 aerial survey was adapted. Recces and camera trapping also used. Effort in km walked per stratum, and total km walked; 84 km of transect; 228 recce Number of transects and length of transects (per stratum: sometimes transects are different lenghts in adjacent strata) or recces: there were 84 transects, each 1km long. Recces were also used between transects. Dung density if available, plus 95% confidence limits, plus %CV; per stratum and per landscape Jolly method 130.95 (95% c.l. 80.88-181.1) Dung encounter rate plus 95% confidence limits, plus %CV; per stratum and per landscape 0.26 dung 194 piles.km-1 on transects and 0.1 dung piles.km-1 on recces. Dung production and decay rates (if used), and whether derived from a time-and-site-specific study (i.e just before the survey), or a site-specific study (at the same site but at a different time), or a study elsewhere (and what it was: reference) Dung production rate of 25.3 (Olivier et al., 2009) and dung decay rate of 57.13 (Walsh & White 2001) were used.