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SummaryDropping counts were used to assess elephant abundance in the remote forests of northeastern Gabon where there are few people and no logging. Elephants prefer the secondary forest which grows on abandoned villages and plantations, but avoid roads and villages. Thus elephant distribution is governed by the distribution of both past and present human settlement, even in the remotest and least disturbed forests of equatorial Africa.RésuméOn a évalué l'abondance des éléphants en comptant les excréments, dans les forêts reculées du nord‐est du Gabon, là où il n'y a que peu de gens et aucun abattage d'arbres. Les éléphants préférent les forêts secondaires qui poussent dans les villages et les plantations abandonnés, mais évitent routes et villages. Donc, la distribution des éléphants est régie par la répartition des installations humaines présentes et passées, même dans les forêts les plus reculées et les moins troublées d'Afrique équatoriale.

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This paper presents the analyses of data obtained from eight permanent 20 km transects to determine the relative effect of local human populations and ecological factors on the distribution of large mammals within the Dzanga sector of the Dzanga-Ndoki National Park and the adjacent area of the Dzanga-Sangha Dense Forest Special Reserve in south-west Central African Republic. Principal component analysis indicated that human activities significantly influence the distribution of large mammals, even within this protected area. Distance from the village and the main road as well as the distance from secondary roads appeared to have the greatest influence. Elephants in particular were significantly less common in areas related to human use. Our study showed that poachers use roads, both primary and secondary, to penetrate into the National Park. Thus increasing anti-poaching efforts along these roads could be an effective protection measure.

A survey of apes was carried out between October 1996 and May 1997 in the Dzanga sector of the Dzanga-Ndoki National Park, Central African Republic (CAR), to estimate gorilla (Gorilla gorilla gorilla) and chimpanzee (Pan troglodytes) densities. The density estimates were based on nest counts. The strip transect census and the line transect survey method (Standing Crop Nest Count) were used to estimate the gorilla nest group density. The strip transect has been most commonly used to date. It assumes that all nest groups within the width of the strip are detected, but as this assumption is easily violated in the dense tropical rain forest, the line transect survey was also used. In this method, only the nest groups on the transect line itself should be detected. This method proved to be an adequate and easy technique for estimating animal densities in dense vegetation. The gorilla density of 1.6 individuals km À2 (line transect survey method) found for the Dzanga sector is one of the highest densities ever reported in the literature for the Western lowland gorilla. The density estimate for chimpanzees was 0.16 individuals km À2 (census method). The results of this study con¢rm the importance of the Dzanga-Ndoki National Park for primate conservation.

The number of elephants living in the forests of Gabon was estimated by a stratified dung survey. The forest zone was stratified according to the distribution of the human population. The density of dung-piles was estimated for each stratum by the line-transect method. The total number of dung-piles in the forests of Gabon was estimated to be 52.43 × 106 ± 13.25 × 106. This gave an elephant estimate of 61,800 ±20,200. This survey shows Gabon to have one of the largest elephant populations on the continent.

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This paper addresses the e¡ect of human activities on the density of large mammals in the Dzanga-Ndoki National Park and the adjacent Dzanga-Sangha Reserve in the Central African Republic.Between six and eight 20 km long permanent transects were walked on a monthly basis from January 1997 to August 1999 to assess large mammal populations as well as human intrusion. There were no obvious seasonal or monthly trends in elephant, gorilla or non-human primate densities.Overall, it appears that human activities negatively in£uence the distribution of most of the large forest animals in Dzanga-Sangha. Elephants in particular were signi¢cantly less common in areas used by humans, but also other species such as non-human primates showed lower densities closer to the main road and the town of Bayanga.This studycon¢rms the ¢ndings of previous studies that roads have a negative impact on wildlife populations.Results of this study stress the need for conservation of large uninterrupted forest blocks to maintain wildlife populations at normal levels. Simply creating roads, even within a protected Central African forest, is likely to have negative impacts on wildlife populations.