Editor’s Choice @Biotropica 48(3): Mapping Hunting Pressure in Central Africa


I am pleased to announce the Editor’s Choice Article for Biotropica 48(3): Stefan Ziegler, John E. Fa, Christian Wohlfart, Bruno Streit, Stefanie Jacob and Martin Wegmann (2016), Mapping Bushmeat Hunting Pressure in Central Africa, 48: 405–412.

There is no doubt that hunting poses a major threat to the persistence of wildlife throught the tropics. Ziegler and colleagues have done a monumental job of summarizing and analyzing data on the hunting of mammals over the course of almost 20 years in Cameroon, Central African Republic, Democratic Republic of Congo, Equatorial Guinea, Gabon, and Republic of Congo. Coupled with data on environmental variables and anthropogenic pressure, protected areas, and population density they use these data to map hunting pressure across the Congo Basin, and show – among other things – that many protected areas are located in high-risk areas. Their threat map provides a means of  identifying areas where hunting is likely to have the greatest impact and to guide large-scale conservation planning initiatives for central Africa.  It’s blend of synthesis, innovative analysis, and impact makes it an important study and an easy selection as for the Editor’s Choice.

Congratulations to Stefan and his coauthors.

Cameroon, near Jakiri Koumengba (photo by jbdodane, CC BY-NC 2.0)

Cameroon, near Jakiri Koumengba (photo by jbdodane, CC BY-NC 2.0).


Stefan Ziegler

In the 1990s, when the synonym of “empty forest” was first mentioned to describe the extirpation of forest mammalian diversity, many of the authors started their career in conservation projects in tropical Africa. Although many local people have traditionally hunted game for subsistence use or for barter, those who most depend on wildlife resources are in a dilemma: their food security is threatened due to presumably non-sustainable levels of hunting. But there is no easy answer to the question what is sustainable hunting?

In 2000, John Robinson and Liz Bennett, in their seminal book ‘Hunting for Sustainability’, invoked an image of the slippery concept of sustainability by comparing it to Lewis Carroll’s ‘snark’, an imagery animal difficult to track down. Almost two decades later, we are probably just as far away from tracking down the fabled animal. In other words, our understanding of the sustainability of hunting in the tropics is still incomplete. But, although we do know much about who hunts and why, as witnessed by the large number of studies that have been published on hunting in the tropics, our understanding of how much is extracted in areas such as the Congo Basin is still sketchy. Knowing where extraction of wild meat occurs is a prime importance in understanding how to tackle the problem of over-exploitation of wildlife. After all, bushmeat extraction, which has no doubt increased substantially during recent decades, is perhaps the most pervasive threat to biodiversity in tropical forests worldwide.

John Fa

We wanted to calculate levels of wild meat extraction throughout the tropical rain forests of Central Africa and see where this occurs at the highest levels. This paper is the first to do this. Previous work had calculated amounts of wild meat (mammals) exploited in the Congo Basin compared to the Amazon Basin but no attempt had been made to map areas of exploitation within these. In order to do this, we had to assemble a strong group of specialists involving remote sensing experts, ecologists, and scientists who had worked on bushmeat hunting in Africa.

The main intention of our work was to find out where and how much wild meat is extracted throughout Central Africa. Our motivation was simple – if it is possible to highlight those areas of the Congo Basin forests that are under higher hunting pressure can we target these for more active conservation actions. A review of the relationship between recent trends of bushmeat trade and various variables of environmental change and development was eye-opening: the greatest challenge associated with the exploitation of the wildlife resources in Central Africa is the paucity of biological and socioeconomic data on a scale that would enhance a thorough understanding of the problem within the sub-region. The remote sensing specialist Martin Wegmann from the University of Würzburg, Germany had an answer to the problem and deployed spatial modelling tools to overcome this hurdle. The initial work to this paper was born and culminated in the elaboration of a Diploma thesis on spatial analysis of bushmeat extraction in Central Africa written by Stefanie Jacob.

Martin Wegmann

Building on Stefanie’s thesis, we increased the number of data on hunting offtake of mammals – published studies conducted between 1990 and 2007 in Cameroon, Central African Republic, Democratic Republic of Congo, Equatorial Guinea, Gabon and Republic of Congo. From these data sources, we estimated annual extraction rates of all hunted species and analysed the relationship between environmental and anthropogenic variables surrounding each hunting rate and levels of bushmeat extraction. We defined hunting pressure as a function of bushmeat offtake and number of hunted species, and analysed the variables that significantly correlated with this. Not surprisingly we found that road density, distance to protected areas and human population density were correlated with hunting levels.

These correlations were then used to map hunting pressure across the Congo Basin. We showed that predicted risk areas show a patchy distribution throughout the study region and that many protected areas are located in high-risk areas. The map produced could help to support sustainable regional planning by ensuring that – as far as possible – roads do not carve up areas rich in wildlife. The map also identifies neuralgic points where the potential for hunting pressure is particularly high. Anti-poaching measures should concentrate on these zones.

Stefan Ziegler
WWF Germany &
Goethe University
Frankfurt, Germany

John E. Fa
Manchester Metropolitan University
Manchester, UK &
Center for International Forestry Research (CIFOR)
Bogor, Indonesia

Martin Wegmann
University of Würzburg
Würzburg, Germany