Okavango Comparative Ecology Study

Okavango Comparative Ecology Study: Livestock and Wildlife Land Use Systems at Risk of Increased Climate Variability

The aim of this project is to initiate exploratory work on long-term ecological change in and around the Moremi Game Reserve by comparing the ecology of livestock and wildlife land use systems. 

Researcher: Andrea Wolf

Background
There is an urgent need to understand how the environment is changing under different land use systems, not least because the economies of Northern Botswana are heavily dependent on the environment, through livelihood strategies ranging from agriculture and hunter-gathering to pastoralism and wildlife-based tourism. The climate is highly variable and predicted to become more so through climate change; indeed preliminary data shows rainfall is already lower and more variable than it was before 1980.

Scientifically, the Okavango region provides an excellent site to measure the effects of different land uses on the environment. The landscape has been artificially divided into three primary uses for several decades (park-tourism; hunting; livestock), and plot level and aerial photography data exist dating back to before the divisions were established. 

Project Details
This study will focus on finer scale data than previous studies, using transect plots, looking at changes in grass cover, woody vegetation (seedlings, shrubs, trees) and wildlife (using dung counts). This level of detail will allow for detailed paramatisation of both predictive models and satellite analyses that is not normally done. The larger research question is whether Social Ecological Systems heavily dependent on browsers like elephant, kudu and impala are responding differently to variability than those that depend on domestic grazing species (i.e. livestock), and whether this has ecological implications for land use decisions and the survival of vegetation (e.g. Zizyphus mucronata) and wildlife (e.g. tsessebe) in the face of climate change.

Objectives
The purpose of this project is to initiate exploratory work on long term ecological change in and around the Moremi Game Reserve (MGR). The baseline and methodology provided by the project will be tracked as part of a much larger study. There is no comprehensive ecological monitoring in northern Botswana, despite the challenges of over-populations of elephant and livestock and the imminent threat of climate change.

The comprehensive monitoring programme includes:
1. Development of detailed baseline soil maps in Moremi Game Reserve

2. Development of baseline and methods for monitoring vegetation change

3. Monitoring of long-term changes in wildlife populations related to habitats

4. Linkages of soil, vegetation and wildlife monitoring to:
a. Satellite-based remote sensing
b. Past and models of future climate change
c. Predictive ecological models that allow prediction for how combinations of elephant and impala or livestock will play out in the future. This project is critical to provide detailed data on the status of vegetation to run these models.

This research will be carried out in collaboration with park managers/researchers in Botswana and will inform Botswana's Department of Wildlife and National Parks. A joint programme with graduate students at the University of Botswana in Gabarone is under discussion.

Studies conducted on the Chobe riverfront, as well as recent newspaper articles in Botswana, suggest that these ecosystems are being simplified, with the loss of both vegetation and mammal species. The objective of this study is to establish a monitoring system to verify this.

A further goal is to establish a long-term ecological monitoring and modelling programme in/around Moremi.

Methodology
180 detailed vegetation/soil transects will be undertaken in the MGR during the next three consecutive dry seasons in three different treatment sites (MGR, surrounding wildlife areas, and rangelands). This area has been selected so as to compare with the baseline FAO survey conducted in the 1960's by Graham Child (who will assist in this project). The new transects will be compared with Dr Child's.

Detailed vegetation work will be used to train satellite imagery of the larger Ngamiland system to assess changes on a much larger spatial scale. It will also be used to model future habitat and wildlife scenarios using well-developed models such as SAVANNA and Q&D which is currently being applied in South Africa's Kruger National Park. 

Outputs
The study will inform park managers of long term changes in land cover and ecosystem health and landowners who may need to make decisions regarding long-term questions of sustainability and profitability of their land. This work will inform management of the Moremi Game Reserve and the eastern Okavango Delta more generally, as the wildlife and tourism industry in the country attempts to reconcile conservation policies with economic development.