Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Titre : Semi-nomadic pastoralism and the conservation of biodiversity in the Richtersveld National Park, South Africa

Auteur : Hendricks HH

Université de soutenance : University of Cape Town

Grade : Doctor of Philosophy (PhD) 2004

Résumé partiel
The thesis presented here is about traditional semi-nomadic pastoralism and the conservation of biodiversity in a semi-arid South African National Park. The aim was to help improve farmer livelihoods without compromising the unique biodiversity of the area, especially the succulent plants. The thesis sets out to analyse the dynamics of pastoral activities with the Richtersveld National Park (RNP), focussing on the relationship between pastoralism and livelihoods ; the impact of grazing on vegetation biodiversity ; and a synthesis of these in order to suggest management strategies to minimise conflicts between pastoralists and conservation interests, both of whom have a stake in the future management of the park. It is currently argued by rangeland theory that by lowering the size of a herd, the productivity of individual animals will increase and that this smaller herd size will conserve rangeland. So, in theory, reduced herd sizes would be beneficial to biodiversity conservation and herd performance. In common with most of pastoral Africa, de-stocking is difficult to implement in the RNP because it is unpopular and there is no clear agreement on which of the 20-odd pastoralists should be reducing their herd size. So how does herd size of a pastoralist influence (a) herd performance and pastoralist livelihood, and (b) biodiversity conservation ? Chapter 1 frames the problem between semi-nomadic pastoralism and biodiversity conservation, using the Richtersveld National Park case study, and so asks what chance is there for a sustainable coexistence between livestock farming and the conservation of biological diversity in communal rangelands ? Chapter 2 describes the physical and ecological aspects of the RNP, including the semi-nomadic pastoral system of the Nama people. Chapter 3 attempts to understand the management of the RNP in the overall context of its management history, livestock population patterns and the importance of livestock in the household economy of pastoralists. Both literature reviews and Participatory Rural Appraisal (PRA) techniques were used to determine the historical profile of the RNP. Livestock populations were counted four times a year (January, April, July and October) between 1995 and 2002. During these visits, pastoralists were interviewed on herd offtake and mortality. Data concerning household meat consumption and monetary income/expenditure were not based on accurate records, but on pastoralists’ estimates. Total stock numbers for the RNP (ca. 4 500 SSU) never exceeded the set carrying capacity of 6 600 SSU during the study period ; goat populations exceeded sheep and cattle by far. Herd number increased from 13 in 1995 to 18 in 2002. The mean herd size recorded was 391 animals. The average income from stock sales was ca. R750 per month compared to pastoralists monthly expenditure of ca. R2 000. Pastoralists slaughtered about two animals per month. Chapter 4 examines the regulatory effect of rainfall on stock numbers, and how herd size and pastoralist interventions and skills impact on livestock performance. The analyses in this chapter are based on the data set collected in Chapter 3. Here, I address the question whether herd size matters for herd performance ; specifically if an increase in herd performance is achieved with smaller herd sizes, if small herds have a higher risk of complete extirpation than larger herds and if herd performance is a function of various production objectives. I found that total stock numbers were regulated by annual rainfall, usually a lag effect of 1-2 years. This study found little relationship between herd size and herd performance, or herd size and density dependent stock losses and recovery rates during a two year drought. Smaller herds have a higher risk of disappearing than larger herds during a severe drought. Herd size manipulation is not an effective intervention for pastoralist livelihood and biodiversity conservation in the RNP Chapter 5 assess the seasonal movement patterns and daily foraging activities of livestock, making use of both GPS and telemetry data collection techniques. The second part of the chapter quantifies the potential impacts of herd movement on conservation-worthy sites. Seasonal herd movements were characterised by regular treks of approximately 10km between the Upland Succulent Karoo veld (`buiteveld’) in the winter and the Orange River pastures in the summer. The average foraging range was 2.5km, ca. 1 900 ha available grazing area. Goats and sheep walked much more quickly in the morning (ca. 1 km/hr) than in the afternoon (ca. 0.5km/hr). During these seasonal movements and daily foraging activities, livestock foraged a large proportion (ca. 60%) of areas with special conservation importance between 1995 and 2001. A few stock posts (ca. 10) were located within the conservation-worthy sites. Chapter 6 explores why pastoralists do what they do in the RNP. This study includes their herd production objectives, stock ownership patterns, and local knowledge about factors influencing herd size. movement from one stock post to another and the underlying motives for decision-making. Here, I used a suite of PRA techniques to collect the relevant data. I found that the traditional pastoral system is witnessing some changes. This is based on my suggestions that people begin to rely more heavily on remittances sent by relatives or allowances from government, the Nama language is mainly spoken by the older people still speak the Nama language make common use of it, animals are also hardly kept for ceremonial (sacrificial) purposes anymore, and the fact that the average pastoralist in this study was older than 50 years and the majority of pastoralists made use of ’hobby farming’. The herd production objectives varied between pastoralists, not all were trying to increase production. Pastoralists followed different approaches to track available resource. Chapter 7 determines the diet selection of goats with a focus on diet composition, plant growth forms, principal and preferred food plants in comparison with the conservation status of food plants. This study includes five-minute feeding observations during the winter rainfall period between 1997 and 1998.

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