DESIGNING A RANGELAND TO PRESERVE AFRICA’S MOST ENDANGERED MAINLAND BIRD AND A PEOPLE’S WAY OF LIFE BRUKTAWIT ABDU MAHAMUED A thesis submitted in partial fulfilment of the requirements b of the Manchester Metropolitan University for the degree of v Doctor of Philosophy Division of Biology and Conservation Ecology School of Science and the Environment Manchester Metropolitan University 2016 Abstract The Borana rangelands once had the highest grazing potential in East Africa and productive breed of cattle. Currently, the rangelands are severely degraded due to increase in human and cattle population, overgrazing, climate change and agricultural expansion. The Liben Plains, located 10 to 40 km from Negelle, is an area of rangeland known to be one of the last remaining stronghold of the Liben Lark (Heteromirafra archeri). The species is currently listed as Critically Endangered, mainly due to habitat degradation, and with a tiny and rapidly declining global population. Research examining the abundance and habitat preferences of the species have been ongoing since 2007. Here I present an analysis of these and additional survey data from 2007 to 2013 regarding the species population size, density and habitat associations, and track changes in the patterns of land-use, habitat loss and degradation over the last 20 years. Distance sampling line-transect surveys were used to assess the density and distribution of the species. Measurements of structural habitat characteristics were also recorded using a standardised habitat recording method in use since 2007. Spatial data analysis revealed that the Liben Plains are experiencing significant and ongoing levels of habitat loss, primarily through the conversion of grassland habitat to cereal crops farming has been evident since 1994, but has accelerated since 2000, and alarmingly, has spread to include areas of red soil grasslands that were previously believed to be unsuitable for agriculture. Density estimates from 2007 to 2013 revealed that the Liben Lark population has declined dramatically across the Plains. The species is now extremely rare, numbering no more than 1 individual per km2, and confined to just three tiny areas of ‘density hotspots’ covering an area of degraded grassland between 10km2 and 26km2 in size. Liben Larks were found to avoid areas of severe habitat degradation i.e. areas of the plains with high bare ground cover, short heavily disturbed grass, high cover of trees and invasive fennel, but preferred areas with medium to tall dense grass (least grazed areas), but patterns of habitat associations varied between differed survey seasons. Nest concealment is a large contributing factor for the survival of artificial lark nests containing artificial lark eggs, which experimental trials in this study reveal suffer extremely high nest failure rates due to predation by birds and mammals, and trampling by livestock. These factors may be restricting the Liben Lark population from breeding effectively. An integrated management system involving state, traditional and non-governmental bodies is crucial to balance grazing land for livestock and suitable habitat for the survival of the Liben Lark. I Acknowledgments First of all, I would like to express my deepest gratitude to my Director of Studies, Dr Huw Lloyd for helping and guiding me all throughout the duration of my thesis work. I am equally very grateful to all my supervisors Prof Stuart J. Marsden, Prof Nigel J. Collar, Dr Paul F. Donald and Dr James Bennett for their tremendous effort and help throughout the study period. I thank the Ethiopian Wildlife and Natural History Society (EWNHS) especially Mengistu Wondafrash and Yilma Dellelegne for all their support. I thank Waariyo Sara, the project officer of the EWNHS at the study site. I am very grateful to Samson Zelleke, Alazar Daka, Zelalem Teffera, Assefa Getachew and Wellelta Sheferaw for all their support during the field work and write up. Finally, my deepest gratitude goes to my family Emama, Huiy, Bubu, Mumu, Redu and Biyo who have supported and encouraged me throughout – I could not have done this without them. This research would not have been possible without the generous funding and support from: (1) an MMU PhD studentship from the School of Science and Environment, Faculty of Science and Engineering, Manchester Metropolitan University; (2) The Leventis Foundation; (3) and the Institutional support from BirdLife International (Cambridgre UK) and the Royal Society for the Protection of Birds (RSPB). I owe them all a great deal of gratitude and thanks, and remain humbled by their faith in me to conduct this research, to try and make practical conservation recommendations to save the Liben Lark from extinction and preserve Borana pastoralism. II Table of Contents Abstract............................................................................................................................................................................................I Acknowledgments.................................................................................................................................................................... II List of Figures ....................................................................................................................................................................... VIII List of tables...............................................................................................................................................................................XI Chapter One ................................................................................................................................................................................ 1 INTRODUCTION............................................................................................................................................................ 1 1.1. Rangelands and Grassland Ecosystems ...................................................................................................... 1 1.1.1. Grassland avian diversity and threats .................................................................................................... 1 1.1.2. Rangeland Management................................................................................................................................. 2 1.2. The Borana Ethiopian rangelands ................................................................................................................. 3 1.2.1. The Gadda system of land management................................................................................................. 4 1.2.2. The Liben Plain, Southern Ethiopia ......................................................................................................... 5 1.2.3. Threats to the Liben Plain ............................................................................................................................. 6 1.2.3.1. Threats from bush encroachment .......................................................................................................... 7 1.2.3.2. Threats from drought and climate change ........................................................................................ 8 1.2.3.3. Use of fenced enclosures and state ranches..................................................................................... 8 1.2.4. Biodiversity on the Liben Plain .................................................................................................................. 9 1.3. The Liben Lark........................................................................................................................................................ 9 1.3.1. Taxonomy and Identification ....................................................................................................................... 9 1.3.2. Behaviour and Song ...................................................................................................................................... 11 1.3.3. Habitat preferences of the Liben Lark ................................................................................................. 13 1.3.4. Nesting behaviour of Liben Lark ............................................................................................................ 13 1.3.5. Threats and the Conservation Status of the Liben Lark.............................................................. 14 1.4. Overall Aim of the PhD and objectives of chapter ............................................................................ 15 1.4.1. Academic Aim ................................................................................................................................................... 15 1.4.2. Objectives ........................................................................................................................................................... 15 1.4.3. Scope of Analysis Chapters ....................................................................................................................... 16 1.5. References .............................................................................................................................................................. 17 Chapter Two............................................................................................................................................................................. 24 PATTERNS OF GRASSLAND HABITAT CHANGE ACROSS THE LIBEN PLAIN.. 24 III 2.1. Abstract ...................................................................................................................................................................