Plumptre Andrew J, Nixon Stuart, Kujirakwinja Deo K, Vieilledent Ghislain, Critchlow Rob, Williamson Elizabeth A, Nishuli Radar, Kirkby Andrew E, Hall Jefferson S
Wildlife Conservation Society, 2300 Southern Boulevard, Bronx, New York 10460, United States of America.
Conservation Science Group, Department of Zoology, David Attenborough Building, Cambridge University, Pembroke Road, Cambridge, United Kingdom.
PLoS One. 2016 Oct 19;11(10):e0162697. doi: 10.1371/journal.pone.0162697. eCollection 2016.
Grauer's gorilla (Gorilla beringei graueri), the World's largest primate, is confined to eastern Democratic Republic of Congo (DRC) and is threatened by civil war and insecurity. During the war, armed groups in mining camps relied on hunting bushmeat, including gorillas. Insecurity and the presence of several militia groups across Grauer's gorilla's range made it very difficult to assess their population size. Here we use a novel method that enables rigorous assessment of local community and ranger-collected data on gorilla occupancy to evaluate the impacts of civil war on Grauer's gorilla, which prior to the war was estimated to number 16,900 individuals. We show that gorilla numbers in their stronghold of Kahuzi-Biega National Park have declined by 87%. Encounter rate data of gorilla nests at 10 sites across its range indicate declines of 82-100% at six of these sites. Spatial occupancy analysis identifies three key areas as the most critical sites for the remaining populations of this ape and that the range of this taxon is around 19,700 km2. We estimate that only 3,800 Grauer's gorillas remain in the wild, a 77% decline in one generation, justifying its elevation to Critically Endangered status on the IUCN Red List of Threatened Species.
格劳尔大猩猩（Gorilla beringei graueri）是世界上最大的灵长类动物，仅分布于刚果民主共和国东部，受到内战和不安全因素的威胁。战争期间，矿区的武装组织依靠猎捕丛林肉，包括大猩猩。格劳尔大猩猩分布范围内的不安全因素以及多个民兵组织的存在，使得评估它们的种群数量变得非常困难。在此，我们使用一种新方法，能够对当地社区和护林员收集的关于大猩猩栖息地的数据进行严格评估，以评估内战对格劳尔大猩猩的影响。战前估计该大猩猩种群数量为16900只。我们发现，它们在卡胡兹－别加国家公园的栖息地数量减少了87%。在其分布范围内10个地点的大猩猩巢穴相遇率数据表明，其中6个地点的巢穴数量减少了82%至100%。空间占有率分析确定了三个关键区域是这种猿类剩余种群最关键的地点，该分类单元的分布范围约为19700平方公里。我们估计，目前仅存3800只野生格劳尔大猩猩，一代内数量下降了77%，这使其在世界自然保护联盟濒危物种红色名录上被列为极度濒危物种。
