Assessing Waterhole Design and Determining the Impact of Artificial Waterholes in Balule Nature Reserve, South Africa
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ASSESSING WATERHOLE DESIGN AND DETERMINING THE IMPACT OF ARTIFICIAL WATERHOLES IN BALULE NATURE RESERVE, SOUTH AFRICA by EILIDH SMITH submitted in accordance with the requirements for the degree of MASTER OF SCIENCE In the subject NATURE CONSERVATION at the UNIVERSITY OF SOUTH AFRICA SUPERVISORS: DR AS BARRETT PROF LR BROWN JANUARY 2016 Declaration I declare that ASSESSING WATERHOLE DESIGN AND DETERMINING THE IMPACT OF ARTIFICIAL WATERHOLES IN BALULE NATURE RESERVE, SOUTH AFRICA is my own work and that all the sources that I have used or quoted have been indicated and acknowledged by means of complete references. 26/01/2016 ________________ _____________________ Eilidh Smith Date Summary Herbivores have a significant influence on their environment. Factors that influence herbivore distribution in a landscape are important for conservation. Artificial water provision is one such factor, with water sources being focal points of herbivore activity. Variation between herbivore utilisation of different waterhole types and habitat integrity surrounding the different waterholes is assessed in this study. Correlations are drawn between herbivore utilisation and habitat integrity to quantify the impact that artificial waterholes have on the landscape. A scoring system is devised to investigate the various factors affecting vegetation around artificial waterholes. Results show that there are significant variations between herbivore utilisation for different artificial waterhole types, as well as significant variation in habitat integrity surrounding the different waterhole types. Distance between waterholes and drainage lines, and utilisation by specific herbivore species have a significant impact on habitat integrity - specifically affecting veld condition and disturbance observed on woody plant species. A habitat score that was created by combining data from both the herbaceous and woody layers is not affected by waterhole type, distance from waterholes, or the different herbivore species utilising the different waterhole types. Earth dams have the greatest impact on surrounding vegetation and are the most utilised waterhole type. Closures of earth dams are not recommended due to their importance to herbivores. Less utilised waterhole types are also important, mitigating the impact of herbivore damage to vegetation at earth dams. Key Terms Artificial waterhole, Balule, habitat integrity, herbaceous layer, herbivore impact, piosphere, woody layer Table of Contents TABLE OF CONTENTS ........................................................................................................................................ 1 CHAPTER 1 : INTRODUCTION ......................................................................................................................... 10 1.1: BACKGROUND ................................................................................................................................................ 10 1.2 HERBIVORE UTILISATION OF WATERHOLES ............................................................................................................ 12 1.3 THE IMPACT OF ARTIFICIAL WATERHOLES ON HABITAT INTEGRITY ............................................................................... 13 1.4 ASSESSING THE INFLUENCE OF HABITAT INTEGRITY FOR SELECTED HERBIVORES ............................................................. 13 1.5 OBJECTIVES .................................................................................................................................................... 14 REFERENCES ......................................................................................................................................................... 16 CHAPTER 2 : STUDY AREA .............................................................................................................................. 21 2.1 LOCATION AND SIZE ......................................................................................................................................... 21 2.2 TOPOGRAPHY AND GEOLOGY ............................................................................................................................. 22 2.3 SOIL .............................................................................................................................................................. 22 2.4 VEGETATION ................................................................................................................................................... 22 2.5 FAUNA .......................................................................................................................................................... 24 2.6 LAND USE HISTORY ........................................................................................................................................... 26 2.7 CLIMATE ........................................................................................................................................................ 26 REFERENCES ......................................................................................................................................................... 28 CHAPTER 3 : METHODOLOGY ......................................................................................................................... 29 3.1 WATERHOLE SELECTION .................................................................................................................................... 29 3.2 HERBIVORE UTILISATION OF WATERHOLES ............................................................................................................ 32 3.2.1 Data collection .................................................................................................................................... 32 3.2.2 Visitations ........................................................................................................................................... 34 3.2.3 Species diversity .................................................................................................................................. 34 3.2.4 Diet ...................................................................................................................................................... 34 3.2.5 Group size and herd type .................................................................................................................... 35 3.2.7 Herbivore activity ................................................................................................................................ 35 3.2.8 Species electivity of waterholes .......................................................................................................... 35 3.3 THE IMPACT OF ARTIFICIAL WATERHOLES ON HABITAT INTEGRITY ............................................................................... 35 3.3.1 Herbaceous layer ................................................................................................................................ 37 3.3.2 Woody layer ........................................................................................................................................ 38 3.3.3 Habitat score ....................................................................................................................................... 38 3.4 ASSESSING THE INFLUENCE OF WATERHOLE DESIGN ON HABITAT INTEGRITY WITH REFERENCE TO SPECIFIC HERBIVORES ........ 39 3.5 STATISTICAL ANALYSIS ....................................................................................................................................... 39 3.6 GIS STUDY ..................................................................................................................................................... 39 REFERENCES ......................................................................................................................................................... 41 CHAPTER 4 : HERBIVORE UTILISATION OF WATERHOLES ............................................................................... 43 4.1 INTRODUCTION ............................................................................................................................................... 43 4.2 METHODOLOGY .............................................................................................................................................. 45 4.2.1 Camera traps....................................................................................................................................... 45 4.2.2 Visitations ........................................................................................................................................... 47 4.2.3 Animal species diversity ...................................................................................................................... 48 4.2.4 Diet ...................................................................................................................................................... 48 Page | 1 4.2.5 Group size and herd type .................................................................................................................... 49 4.2.6 Herbivore activity ................................................................................................................................ 50 4.2.7 Species electivity of waterholes .......................................................................................................... 51 4.2.8 Statistics .............................................................................................................................................