The mammal survey was carried out using line transect techniques and the information on seen animals 

 and indirect signs (faecal drops) was referred to the corresponding plot. For analyses of the available 

 data we selected species on the basis of 1) importance for local people (duikers {Cephalophus spp.), 

 bushtailed porcupine (Atherurus africanus), and small diurnal monkeys), 2) charismatic and 

 international conservation value (gorilla {Gorilla gorilla), chimpanzee {Pan troglodytes), elephant 

 (LoxodontaAfricana), 3) total protection status in Gabon (aquatic chevrotain {Hyemoniscus africanus) 

 and yellow backed duiker {Cephalophus sylvicultor)) ( Table i). 



Table 1 : Common and scientific names of the mammal species selected for our analysis 



Plots were also characterized by a series of biophysical parameters: topographic position, canopy cover, 

 abundance of understorey vegetation, abundance of herbaceous species {Maranthaceae, Zingiberaceae 

 or ferns), abundance of lianas and soil type. All plots where characterized by their distance to 

 waterways, to main roads and to villages. Signs of human activities, such as logging damage or 

 infrastructures (gaps, roads, skidding trails, log yards) and hunting indices (snares, cartridges, hunting 

 camps) were also recorded for each plot. Small rivers, villages and main roads where digitised from a 

 1/50 000 map and integrated on a GIS where the biophysical characteristics of plots and human and 

 mammal signs were also added. A multiple correspondence analysis (MCA) was computed using 

 XIstat2006® to identify the biophysical and human factors that better explain the distribution of 

 mammal species within the logging concession. A linear regression and Spearman correlation test were 

 also computed to examine if the probability of encounter of a species co-varied with the main 

 discriminant variables obtained with the MCA. For species that showed no linear correlation, we used 

 the t-test to detect significant differences between means. 



The GIS maps show that 20% of the concession is located less than 3 km from a main roads and less than 

 5 km from a village. Most hunting traces are located less than 3 km from the main roads or at less than 5 

 km from the bigger cities (Rabi, Mandji, Guietsou, Mbongoul ). We found a strong significant positive 

 correlation (Spearman Coef = 0.676; p<0,000) between hunting traces and distance from roads. The 

 habitats that sustain the highest mammal richness are the lowland dense forests and the savanna-forest 

 mosaics. Results of a Multiple Correspondence Analysis show that the distribution of mammals within 

 the forest concession is more influenced by roads and hunting than by the direct effects of logging 

 (figure 2). Small diurnal monkeys were found far from the villages and between 3 and 10 km from the 

 main roads (Figure 3). Elephants were equally found close or far from roads and don't seem to be 

 affected by hunting activities. Red duikers avoided hunted zones and were significantly more abundant 

 far from roads. Other species like gorillas, chimpanzees or forest buffaloes showed no negative 

 relationship with distance to roads and were observed close to villages. 



Nature & Faune Vol. 23, Issue 1 12 



