Land Cover Assessment in the Habitat of the Chimpanzees in the Boé Sector, Guinea-Bissau

By David Studer

Abstract
For wildlife conservation purposes, monitoring of land cover changes with satellite data has increasingly become a standard tool. An understanding of the dynamics of land cover change is crucial for the successful protection of wildlife. The aims of this research were to conduct a land cover and land cover change assessment for the Boé sector in Guinea-Bissau, an area which serves as habitat to one of the largest remaining chimpanzee populations in Western Africa. In recent years, in addition to population growth and expansion of agriculture, an increase of mainly cashew plantations has been observed, which intensifies the pressure on the chimpanzees' habitat. Therefore, a land cover- and land cover change classification have been made for the years 2018 and 2014. Remote sensing data from Landsat was used. A random forest classifier was implemented for the land cover classification. The results show areas of the Boé sector with a high proportion of forest and a potentially low population density which might serve as future habitat of the chimpanzees. However, the classification of cashew, due its similarity to forest, did not succeed. The random forest classifier achieved an overall classification accuracy of 89.1 % with a classification error of 15.6 % for cashew. But visual validation suggests an over-classification of cashew. Similar observations have been made for cropland. No trends could therefore be derived from the land cover change classification. Nonetheless, field observation suggest an increase of pressure on the habitat of the chimpanzees in the Boé due increased cultivation of cashew. The study showed that the land cover classification for this area of Africa remains a challenge due the present agricultural practices. For future studies, a land cover monitoring approach is needed for deriving changes in land cover and for understanding the interaction between land cover change and socio-economic factors, all of which are crucial factors for the successful protection of the chimpanzees in the Boé.