In February-early March 2008, the fifth aerial census (the fourth by the Laboratory of Applied Ecology) of the Pendjari Biosphere Reserve was carried out. This exercise aims to collect regular data on the state of animal populations. It is based on the fixed band transect census methodology. This year 22 transects representing a total length of 1161.6 km were carried out using a CESSNA, representing 9.9% of the Reserve. Data processing and analysis are carried out according to the method of Jolly II (1969). Only species for which at least 5 contacts were made were considered for statistical analyses. Thirteen species, ten of which were subject to statistical processing, were encountered during the 2008 census. The most encountered species are small antelopes (61 contacts), then cobes (40 contacts) and hippotragues (29 contacts). However, the highest numbers of individuals were observed for buffalo (184 individuals), followed by hippotragues (143 individuals) and buzzards (112 individuals). The frequency of encounters of individuals per transect is therefore higher for the buffalo, i.e. 8.8 individuals/transect, the hippotrague (6.3 individuals/transect) and the buballa (5.2 individuals/transect). The buffalo is the most abundant species in the Reserve with an average population of 1865 individuals. It is followed by the hippotrague, the bubale and the cobes with respective numbers of 1444, 1136 and 984 individuals. Elephants have a low abundance estimated at 669 individuals, but present the highest contribution to biomass (426 kg/km²) due to their very high live weight. The other largest weight contributions are those of buffalo (98 kg/km²), hippotragues (53.6 kg/km²) and buzzards (24.1 kg/km²). Comparison with data from previous counts shows an increase in the numbers of Moth and Hippotragus, and in particular in the numbers of cobes and small antelopes. As for the largest mammals, the buffalo and the elephant, there is a decrease in their numbers which must be the consequence of migration to areas adjacent to the RBP, which are better and better managed and offer a high reception capacity, due to their low load rate in the past. This hypothesis can easily be verified if all adjacent reserves (Arly and W) adopted the same concerted policy for monitoring wildlife populations. We can therefore understand how much we regret this lack of contribution and harmonization of wildlife counting exercises on the part of the managers of the Arly and W Regional Park reserves, especially since the results of this exercise are useful for better planning of surveillance and development activities in all the contiguous protected areas of this vast ecological complex. From the results obtained from this count, it should be noted that the annual series of counts in February or April are complementary and very useful in better explaining the seasonal and inter-annual fluctuations in wildlife populations.

 

Prof. Dr. Ir. Brice SINSIN

Ir. Etotépé A. Sogbohossou

Georges NOBIME Mama ADI

Laboratory of Applied Ecology

Faculty of Agricultural Sciences

University of Abomey-Calavi

Tel/Fax: 21 30 30 84