Biodiversity Surveys within Protected Areas

The human population density in the Albertine Rift is the highest on the continent reaching 5-700, people per square kilometer. As a result of this, the pressures on protected areas are magnified by the demand for land by an ever-increasing population, and less and less free land.

In an attempt to reduce the conflict between people and the parks, efforts have been made to allow controlled access to many of the protected areas. This allows the sustainable harvesting of certain products. However, where this has been implemented, there have been no prior surveys to determine the areas of importance for conservation within the protected areas, and which should remain protected from human disturbance.

Consequently, WCS launched a programme of surveys within some of the forests of the rift to develop zoning plans based on biological criteria. Surveys have been made in Nyungwe forest in Rwanda, and all the forests in western Uganda from Echuya Forest Reserve to Semliki National Park. Nyungwe forest was the first forest to be surveyed and is used as an example of the type of product that comes from the surveys.

Three taxa are surveyed: large mammals, birds and plants. This is because there are reasonable keys for these taxa and because they represent three types of biodiversity.

1. Large mammals are always targeted first by hunters and indicate the levels of poaching that have occurred.
   
2. Birds are useful because there are many species and you can look at feeding guilds (frugivores, insectivores, gramnivores etc)
   
3. Plants do not move and hence represent the diversity of the habitat which probably influences insects and other invertebrates.

The forest is divided into sectors and each sector is surveyed relatively intensively so that a good proportion of the total species are counted. The species richness, diversity and number of endemic species are counted for each sector and mapped. The images below show the difference in total species numbers and endemic species numbers for Nyungwe Forest birds.

Bird species richness	Albertine Rift endemic birds

The maps are then combined for the three taxa weighting by endemic and threatened species to produce one composite map using a complementarity analysis. This effectively shows which sectors are most important for conservation of these three taxa in the forest. It is hoped by combining three very different taxa that they will act as surrogates for other biodiversity.

This map shows the results of combining the three taxa, weighting for endemic species for Nyungwe Forest. These results are then combined with results from the socioeconomic surveys around the forest to identify sites that can be used by local people at minimum cost to the conservation of the forest