Model-Based Suitability and Connectivity Analysis of Lion and Zebra Habitats in a Wildlife-Human Interaction Region of Northern Namibia
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Technische Universität München Model-Based Suitability and Connectivity Analysis of Lion and Zebra Habitats in a Wildlife-Human Interaction Region of Northern Namibia Modelbasierte Habitateignungs- und Konnektivitätsanalyse für Löwen und Zebras in einer Mensch-Tier Interaktionszone in Nordnamibia Wissenschaftliche Arbeit zur Erlangung des Grades Master of Science (M.Sc.) Geprüft von Prof. Dr. Ralph Kühn, Lehrstuhl für Zoologie Betreut von Prof. Dr. Ralph Kühn, Kenneth Uiseb, Tammy Hoth, Dr. Philip Stander Eingereicht von Elisabeth Kirchner (03700594) Eingereicht am 23.07.2020 Eidesstattliche Erklärung Eidesstattliche Erklärung Hiermit versichere ich, dass die vorliegende Masterarbeit ohne Hilfe Dritter und nur mit den angegebenen Quellen und Hilfsmitteln angefertigt wurde. Alle verwendeten Passagen wurden kenntlich gemacht. Diese Arbeit hat in gleicher oder ähnlicher Form noch keiner Prüfungsbehörde vorgelegen. Elisabeth Kirchner Freising, 23.07.2020 II Abstract Abstract Context In northern Namibia, carnivores and large, mammal herbivores are of high eco- nomic importance as they contribute to the touristic value of the region but are also threat- ened by anthropogenic actions as habitat conversion often results in population declines and extinctions. Habitat suitability models are a practical tool to detect relevant habitat patches and wildlife corridors. The knowledge of these can support management decisions on how to prioritize conservation actions to establish stable wildlife populations. Objectives The thesis goal was the detection of suitable habitats for Hartmann’s mountain zebras (Equus zebra hartmannae), plains zebras (Equus quagga) and lions (Panthera leo) as well as possible hybridization zones between the two ungulates in an area between Etosha National Park and Skeleton Coast National Park in Namibia. Besides, preferred habitat patches of lions and their linkages were computed to see if there is a lion corridor that connects Etosha National Park and Skeleton Coast National Park. Methods Habitat suitability models for Hartmann’s mountain zebras, plains zebras and li- ons were created. The selection and weighting of the included parameters were based on literature review and expert opinions. Lion corridors were computed through least-cost connectivity analysis with the ArcGIS Spatial Analyst Toolbox and the Linkage Mapper Toolbox. The results were validated by telemetry data, distribution maps and home range maps. Results Hartmann’s mountain zebras have their main habitat suitability in the escarpment between Etosha National Park and Skeleton Coast National Park and a high habitat suit- ability for plains zebras occurs inside Etosha National Park. The highest hybridization risk between Hartmann’s mountain zebras and plains zebras was detected in the western part of Etosha National Park. Suitable habitats of lions were found to be mainly inside protected areas. A lion corridor between Etendeka Concession and Palmwag Concession was de- tected that enables movements of lions between the Etosha National Park and Skeleton Coast National Park. A second corridor was found that can function as an alternative lion corridor between the north-western part of Etosha National Park and Skeleton Coast Na- tional Park. Conclusions The corridor between Etendeka Concession and Palmwag Concession offers ideal conditions for the realization of a protected wildlife corridor that connects Skeleton Coast National Park and Etosha National Park. The northern corridor is also of high im- portance as it can lower the pressure on the southern corridor. The thesis focuses on the habitat suitability of lions, Hartmann’s mountain zebras and plains zebras but also provides a general approach on how to support management decisions in conservation planning. III Acknowledgement Acknowledgement I would like to express my gratitude to everyone who supported me during the development process of this master’s thesis in Germany and Namibia. I would like to thank my supervisor Prof. Dr. Ralph Kühn from the Chair of zoology at the Technical University of Munich whose door was always open when I needed advice on the thesis, who constantly supported my progress in Germany and Namibia and introduced me to this vulnerable network of wildlife specialists in Namibia. Moreover, I would like to thank William Versfeld from the Ongava Research Centre and the Namibian Lion Trust for his constant help in the data acquisition and the introduction to a great network as well as for his hospitality, organizational and specialist support at the Namibian Lion Trust camp in Namibia. A special thank you also goes to Tammy Hoth, director of the Namibian Lion Trust, for sharing her expertise in lion behavior, giving me access to the data of the Namibian Lion Trust and the great hospitality at the Namibian Lion Trust camp. Moreover, I would like to thank Kenneth Uiseb, Deputy Director of the Wildlife Research and Monitoring Division of the Ministry of Environment and Tourism (MET) in Namibia, for sharing his expertise in zebra behavior and wildlife conservation, the sharing of valuable data and this support during my visit to Namibia. I would also like to thank John Mendelsohn, Ongava Research Centre, for the data support and the offered hospitality during the uncertain times of the corona crisis. I want to thank Dr. Patrick Keilholz for his academic, professional and personal advice and Philipp Huttner, both from DHI WASY, for the help in data management and GIS work- flows. Besides, I would like to thank the following persons and institutes for the sharing of infor- mation, data and the given access: Katharina Diedericks from NASCO, Sophie Haupt from the African Wildlife Tracking, Axel Hartmann from the Etosha Ecological Institute, Piet Bey- tell and Shayne Kötting from the Ministry of Environment and Tourism of Namibia, Jackson Kavetu and Scott Kapi from the Namibian Lion Trust, Lise Hansson from the Kwando Car- nivore Project as well as the conservancies Ehirovipuka, Orupupa, Omatendeka, Anabeb and !Khoa di //Hoas and the protected areas Hobatere concession. Finally, I would like to express my gratitude for the personal support of my family as well as to my boyfriend Sebastian Stasch who accompanied me to Nambia. Elisabeth Kirchner IV Table of Contents Table of Contents 1 Introduction ............................................................................................................. 1 2 Material and Methods.............................................................................................. 3 2.1 Study Area ...................................................................................................... 3 2.1.1 Climate .............................................................................................. 4 2.1.2 Hydrology .......................................................................................... 6 2.1.3 Geomorphology................................................................................. 7 2.1.4 Flora .................................................................................................. 8 2.1.5 Fauna ................................................................................................ 9 2.1.6 Area Status ..................................................................................... 10 2.2 Species ......................................................................................................... 13 2.2.1 Zebras ............................................................................................. 13 2.2.2 Lions ............................................................................................... 19 2.3 GIS Modeling ................................................................................................ 26 2.3.1 Geodata Preprocessing .................................................................. 26 2.3.2 Habitat Suitability Models ................................................................ 36 2.3.3 Resistance Surface ......................................................................... 51 2.3.4 Habitat patches for Lions................................................................. 51 2.3.5 Least-Cost Connectivity Analysis with the ArcGIS Spatial Analyst Toolbox ........................................................................................... 52 2.3.6 Least-Cost Connectivity Analysis with the Linkage Mapper Toolbox ........................................................................................................ 52 3 Results ................................................................................................................... 53 3.1 Telemetry Data ............................................................................................. 53 3.2 Habitat Suitability Model for Mountain Zebras .............................................. 58 3.3 Habitat Suitability Surface Plains Zebras ...................................................... 62 3.4 Comparison of Mountain Zebra and Plains Zebra Suitable Habitats ............. 66 3.5 Habitat Suitability Surface for Lions .............................................................. 67 3.6 Cora Areas for Lions ..................................................................................... 69 3.7 Least-Cost Connectivity Analysis with the ArcGIS Spatial Analyst Toolbox .. 73 3.8 Least-Cost Connectivity Analysis with the Linkage Mapper Toolbox ............ 75 V 4 Discussion ............................................................................................................