Table 1

Regional and country-specific abundance estimates for western lowland gorillas and central chimpanzees (with 95% CIs), plus areas of forest, PAs, and FSC-certified concessions. Also shown by country: percentage of regional gorilla and chimpanzee populations; percentage loss of gorillas 2005–2013; area of forest as given by Verhegghen et al. (53) apart from Angola, for which Global Forest Watch data (http://www.globalforestwatch.org/country/AGO/4) were used; and percentage of total regional forest cover per country. Information on PAs and FSC certification was downloaded from the WRI Interactive Congo Basin Forest Atlases (http://www.wri.org/our-work/project/congo-basin-forest-atlases), apart from Angola (Cabinda), for which we used the legal document for the creation of Mayombe National Park (http://extwprlegs1.fao.org/docs/pdf/ang118430.pdf). For Cameroon, the area south of the Sanaga River only is included, which is within the range of western lowland gorillas and central chimpanzees.

SubspeciesYear/
measurement
CameroonCARCongoEquatorial
Guinea
GabonAngolaRegional totals
Gorilla g. gorilla200549,379
(45,497–127,517)
5,985
(4,862–12,938)
264,655
(242,633–309,516)
2,325
(1,510–3,476)
123,869
(95,667–242,293)
3,086
(2,188–6,355)
449,300
(424,244–595,564)
201338,654
(34,331–112,881)
4,695
(3,872–9,705)
215,799
(180,814–263,913)
1,872
(1,082–3,165)
99,245
(67,117–178,390)
1,652
(1,174–3,311)
361,919
(302,973–460,093)
% of total10.71.359.60.527.40.5100
% loss21.721.618.519.519.919.4
Pan t. troglodytes2005–201321,489
(18,575–40,408)
2,843
(1,194–4,855)
55,397
(42,433–64,824)
4,290
(2,894–7,985)
43,037
(36,869–60,476)
1,705
(1,027–4,801)
128,760
(114,208–317,039)
% of total16.72.243.03.333.51.3100
Forested areakm2117,44569,888213,10021,560224,6006,045652,638
% of total18.010.732.73.334.40.9100
PAs (IUCN categories
I–VI)
km218,8535,46732,6324,34634,2161,93097,444
% of total19.35.633.54.535.12.0100
FSC-certified
concessions
km29,105026,069020,677055,851
% of total16.3046.7037.00100