Human influence on the population dynamics of large herbivores

Published on
October 30, 2013

Insights into the processes that influence population size are vital to the conservation of wild species in terrestrial ecosystems. Until recently, little attention has been paid to the role of humans in this issue. This is in spite of the fact that almost all terrestrial ecosystems are influenced by human activities that, in all likelihood, influence the natural course of animal populations in turn. “I have researched the role of both natural and human processes in relation to the population of large herbivores”, says Edson Gandiwa, who was awarded a PhD for his research by Wageningen University on 29 October.

“I have also looked into how policy instruments can influence human activity and the conservation of nature in a semi-arid savannah ecosystem  within the context of the Gonarezhou National Park in Zimbabwe.”

Under the Communal Areas Management Programme for Indigenous REsources  (CAMPFIRE), those who live in ‘communal areas’ bordering Zimbabwe’s national parks share in the income from the commercial exploitation of the wildlife. When these programmes are successful, the number of conflicts between people and wild animals is decreased.

The research showed fluctuations in the intensity of illegal hunting, a prime example of human influence. These fluctuations corresponded to variations in how strongly the law was enforced. In 2004, a number of extra park watchers were employed so that more of the park could be patrolled. This resulted in less illegal activity. “Consequently, my results show that political instability – between 2000 and 2008 there was instability due to President Mugabe’s land reforms – does not necessarily lead to increased illegal hunting, and certainly not if policy instruments such as laws are passed and enforced.”

During the nineties, most newspapers reported how successful wildlife conservation in Zimbabwe was. That changed, however, after the land reforms began in 2000. The international media lost interest in Zimbabwean wildlife conservation. The international media’s focus also changed. They began to write more about political instability and land reforms and efforts with regards to wild life conservation were treated negatively. Edson Gandiwa: “The coverage spoke of how a ‘spill-over effect’ from the political unrest accompanying Zimbabwean land reforms was impacting on wildlife conservation.”

The dissertation provides new insights into the processes influencing the population dynamics of large herbivores in a semi-arid savannah ecosystem dominated by humans. These processes consist of diverse wildlife management regimes  and emphasise the importance of media framing and both the representation and misrepresentation of problems by wildlife management after political instability, crisis or societal unrest. As a result of these findings, Edson Gandiwa has concluded that natural processes such as drought influence the population dynamic of large herbivores from the bottom-up. In contrast, policy instruments, incentives, facilities and societal frameworks mainly exercise a top-down influence on the populations of wild, large herbivores in savannah ecosystems .