RUMPED ELEPHANT-SHREWS (GRES) (Rhynchocyon Chrysopygus) IN
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ASSESSING THE ABUNDANCE AND NESTING BEHAVIOUR OF GOLDEN- RUMPED ELEPHANT-SHREWS (GRES) (Rhynchocyon chrysopygus) IN ARABUKO-SOKOKE FOREST, KILIFI COUNTY, KENYA ONDORO RAEL NELLY NYANCHAMA A thesis submitted in partial fulfillment of the requirements for the Degree of Master of Science in Environmental Science of Pwani University. May, 2020 ii DECLARATION This thesis is my original work and has not been presented in any other University or any other Award. Ondoro Rael N. Nyanchama MG20/PU/36233/17 Signature: Date: 08/03/2021 We confirm that the work reported in this thesis was carried out by the candidate under our supervision. 1. Dr. Benards Okeyo Department of Environmental Science Pwani University Signature: Date: 08/03/2021 2. Dr. Colin Jackson, National Director A Rocha Kenya, Watamu, Kenya Signature: ___________________ Date: 08/03/2021 iii DEDICATION “Conservation is a cause that has no end. There is no point at which we will say our work is finished.” Rachel Carson. iv ACKNOWLEDGEMENTS First, I would like to thank the Almighty God for the strength and courage that He bestowed upon me making the completion of this work possible. Many thanks to Nature Kenya and Mohammed Bin Zayed Funding for Nature for their financial support. My sincere gratitude to my supervisors Dr. Bernards Okeyo and Dr. Colin Jackson for tirelessly providing professional guidance throughout this period. Special thanks to the Community Forest Association, Forest guards, and research assistants led by Mr. Willy Kombe. I extend my gratitude to Mr. Francis Kagema of Nature Kenya for providing support in many ways especially on the fieldwork. I am also grateful to my wonderful family for their assistance, encouragement, and support throughout the study. Since I may not be able to mention each person individually, I am sincerely grateful to each person who in one way or another contributed to the success of this thesis. v ABSTRACT The Golden-rumped Elephant-shrew (GRES) (Rhynchocyon chrysopygus) is an insectivorous mammal endemic to Arabuko-Sokoke Forest (ASF) and environs. It is listed as Endangered by the International Union for Conservation of Nature (IUCN) Red List. Previous population monitoring studies showed that the GRES population has been decreasing from ASF with the decline attributed to a change in the forest quality resulting from demand for forest products. However, these studies were conducted over a decade ago. This study aimed to assess the abundance, and influence of deadwood volume on nest sightings across the Cynometra, Brachystegia and Mixed Forest vegetation types in ASF. Line transects of 100m length were used to collect data on nesting behaviour while one 10 by 10m quadrat at the centre of each transect was used to collect deadwood data. Distance sampling method, utilizing detection probability data was used to determine the abundance in each of the vegetation types. Linear regression models were employed to examine the association between the number of nests per transect and deadwood volume while means and proportions were calculated to examine the determinants of GRES nesting sites. A total of 44 transects were laid across the three main vegetation types. Findings from this study indicate that the GRES population was estimated to be 19,423. Besides, deadwood volume was not associated with the number of nest sightings. Nests were found in areas with higher canopy cover, litter depth, and vegetation density. Although findings from this study indicate an increase in the GRES population in ASF, there is a need to continue monitoring their numbers to inform guidelines and conservation measures. There should be continued support to the community to improve their livelihoods to reduce the pressure for forest products and degradation which threatens flora and fauna including GRES with extinction. vi TABLE OF CONTENTS DECLARATION ............................................................................................................. ii DEDICATION ................................................................................................................ iii ACKNOWLEDGEMENTS ............................................................................................ iv ABSTRACT ......................................................................................................................v LIST OF FIGURES ..........................................................................................................x LIST OF TABLES ......................................................................................................... xii ABBREVIATIONS AND ACRONYMS ..................................................................... xiii CHAPTER 1: INTRODUCTION .....................................................................................1 1.1 Background Information .........................................................................................1 1.2 The Problem Statement ...........................................................................................5 1.3 Objectives of the Study ...........................................................................................6 1.3.1 General Objective .............................................................................................6 1.3.2 Specific Objectives ...........................................................................................6 1.4 Research questions ..................................................................................................6 1.5 Significance of the Study ........................................................................................6 1.6 Ethical Considerations in the Study ........................................................................8 1.7 Limitations of the Study ..........................................................................................8 CHAPTER 2: LITERATURE REVIEW ..........................................................................9 2.1 A general overview of small mammals ...................................................................9 2.2 Distribution of Small Mammals ..............................................................................9 2.3 Elephant Shrews ....................................................................................................12 2.3.1 Description of Elephant Shrews .........................................................................13 2.3.1.1 Golden-rumped Elephant-Shrew .....................................................................14 vii 2.3.1.2 Other Giant Sengis .........................................................................................15 2.3.1.3 Other types of elephant shrews .......................................................................15 2.3.2 Distribution of Elephant Shrews ........................................................................16 2.3.3 Ecology and Behaviours of Elephant-Shrews ....................................................17 2.3.3.1 Habitats............................................................................................................17 2.3.3.2 Diet and Foraging ............................................................................................18 2.3.3.3 Activity Patterns ..............................................................................................19 2.3.3.4 Mating and Courtship ......................................................................................20 2.3.3.5 Reproduction and Parenting ............................................................................21 2.3.4 Ecological Importance of Elephant Shrews .......................................................21 2.3.5 Effect of Habitat Changes on the Ecology of Small Mammals and Elephant- Shrews………………… .............................................................................................22 2.3.6 Conservation of Small Mammals and Elephant Shrews ....................................24 2.3.7 Socio-Economic Benefits of Small Mammals ...................................................26 2.3.7.1 Creation of Jobs ...........................................................................................26 2.3.7.2 Creation and Support of local business .......................................................26 2.3.7.3 Boost to Tourism .........................................................................................26 2.3.7.4 Development of Infrastructure .....................................................................27 2.3.7.5 Empowerment of the Local Communities ...................................................27 2.3.7.6 Ecosystem Services .....................................................................................27 2.3.7.7 Option Value................................................................................................28 2.3.7.8 Existence Value ...........................................................................................28 2.4 Arabuko-Sokoke Forest.........................................................................................28 2.4.1 Flora in Arabuko-Sokoke Forest ....................................................................28 viii 2.4.2 Fauna in Arabuko-Sokoke Forest ...................................................................29 2.4.3 Status of Arabuko Sokoke Forest ...................................................................30 2.4.4 Local, National, Regional and Global Value of Arabuko Sokoke Forest ......31 2.4.5 Threats to Arabuko Sokoke Forest .................................................................31