Census of gorillas in northern Republic of Congo

We censused gorilla populations in northern Congo from February to April 1989 and June 1990. The objective was to provide the first quantitative data from a variety of sites on gorilla populations from a country that had unknown but potentially high populations. The method used was a census of nests along strip transects. A total of 401.0 km of transects was sampled in four different study areas. The overall density calculated for all transects was 0.4 nesting gorillas/km². The highest density, 1.2 nesting gorillas/km², was found in the vast Likouala swamp area of north central Congo. The two northern sites showed low densities of 0.1 and 0.2 nesting gorillas/km², respectively. The northwestern site showed an intermediate density of 0.6 nesting gorillas/km². The vegetation type with the highest density was swamp forest with 2.4 nesting gorillas/km². The limited sample presented shows that gorillas are widespread and common in northern Congo, even in the swamp forests previously considered unsuitable as gorilla habitat. It is probable that Congo holds the largest population of gorillas in Africa after Gabon. © 1992 Wiley-Liss, Inc.