Population structure, movement and health status of elephants and other wildlife in the Selous-Niassa Wildlife Corridor, southern Tanzania

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1 AUS DEM INSTITUT FÜR ZOO- UND WILDTIERFORSCHUNG (IZW) IM FORSCHUNGSVERBUND BERLIN E.V. EINGEREICHT ÜBER DIE PROFESSUR FÜR INTERDISZIPLINÄRE ZOO- UND WILDTIERFORSCHUNG DES FACHBEREICHES VETERINÄRMEDIZIN DER FREIEN UNIVERSITÄT BERLIN Population structure, movement and health status of elephants and other wildlife in the Selous-Niassa Wildlife Corridor, southern Tanzania INAUGURAL-DISSERTATION zur Erlangung des Grades eines Doktors der Veterinärmedizin an der Freien Universität Berlin vorgelegt von Donald Gregory Mpanduji Tierarzt aus Sengerema-Mwanza, Tansania Berlin 2004 Journal-Nr.: 2827 i

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3 Gedruckt mit Genehmigung des Fachbereichs Veterinärmedizin der Freien Universität Berlin Dekan: Erster Gutachter: Zweiter Gutachter: Dritter Prüfer: Prof. Dr. L. Brunnberg Prof. Dr. Dr. H. Hofer PD Dr. S. Dahms Prof. Dr. Weyrauch Deskriptoren: migration corridor, satellite tracking, home range, habitat preference, population structure, elephant, Selous-Niassa Tag der Promotion: i

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5 Table Index CONTENT TABLE INDEX... III FIGURE INDEX... V ABBREVIATIONS... VII 1. INTRODUCTION Overview of wildlife conservation The Selous-Niassa Ecosystem Conservation and development in the Selous-Niassa Wildlife Corridor Research objectives LITERATURE REVIEW Overview of elephant population in the Selous Corridor concept and definition Corridor identifications and design MATERIAL AND METHODS Description of the study site Public village meetings Individual questionnaire-based interviews Field observations Field patrols by village game scouts Crop damage, human and livestock injuries or death Elephant immobilization and radio-collaring Capture procedures Delivery systems and immobilizing drugs Monitoring of anaesthesia Haematology and blood chemistry Satellite-based radio-tracking of elephants Data analysis RESULTS Status and distribution of wildlife Status and distribution of elephants Losses of crops: the role of wildlife Attacks on humans and livestock by wildlife Wildlife utilization and poaching Immobilization and assessment of physical conditions in elephants Major elephant movement routes Seasonal elephant movements...47 i

6 The Selous-Niassa Wildlife Corridor 4.9 Common food plants of elephants Comparing the GPS and Argos satellite location data Elephant home ranges Cumulative home range characteristics Elephant travelling distances Habitat selection and utilization by elephants DISCUSSION Status and distribution of elephants Surveying wildlife: comparing low tech and high tech approaches Elephant capture, immobilization and assessment of physical status Elephant home ranges and movements Habitat use by and preference of elephants Corridors and population persistence People and wildlife The future conservation status of the SNWC in southern Tanzania SUMMARY ZUSAMMENFASSUNG REFERENCES APPENDIX: SCIENTIFIC NAMES OF WILDLIFE SPECIES APPENDIX: QUESTIONNAIRE ACKNOWLEDGEMENTS CURRICULUM VITAE ii

7 Table Index TABLE INDEX Table 1: Details of villages in the study area where village public meetings, individual questionnaire surveys and field observations were conducted. Villages along the north of the Songea-Tunduru road belong to the northern section of the Selous Niassa Wildlife Corridor (SNWC), villages south of the road to the southern section of SNWC...15 Table 2: Estimates of dosage for immobilization of elephants. (Etorphine was available at a concentration of 9.8mg/ml, and Azaperone at a concentration of 40 mg/ml) Table 3: Status and distribution of wildlife species as assessed by village group discussions, individual questionnaire-based interviews and aerial censuses during the wet and dry season Table 4: Village areas where field observations for elephant signs were carried out, including encounter densities for each area Table 5: Crop raiding wildlife species, damaged growth stages, type of damage and expected losses Table 6: Report of the crop damaged by larger wild animal species in Songea Rural (Namtumbo) District from 1990 to Table 7: Total area of mixed crops cultivated and the total damage caused by weeds, diseases, small pest species (rodents, birds), elephants and other large mammals in Songea Rural (Namtumbo) District as reported by the District Agriculture Office...34 Table 8: Monthly distribution of the number of livestock killed by wild animals in Songea Rural (Namtumbo) District for the period from 1990 to Table 9: Signs of poaching activities observed during field observations in different village lands...38 Table 10: Date, time, location, sex, type of drug, dose and posture of elephants immobilized in different areas of the Selous-Niassa wildlife corridor in southern Tanzania...40 Table 11: The shoulder height, sex and age group definition from eleven elephants darted in the Selous-Niassa wildlife corridor in southern Tanzania...41 Table 12: Immobilization, haematology and blood chemistry values in elephants from different areas of the Selous Niassa Wildlife Corridor in southern Tanzania...42 Table 13: Major river systems in the centre of the Selous-Niassa Wildlife Corridor associated with elephant presence Table 14: Trees, shrubs and grass species eaten by elephants as food in the Selous- Niassa Wildlife Corridor as reported by local people...53 Table 15: The characteristic of the GPS and ARGOS Satellite data acquired from the second generation Telonic radio-collars used on 10 elephants in the SNWC from Table 16: Comparison between the number of position fixes and the mean monthly home range between the Argos and GPS system from months where both data were available for the elephants radio-collared in the Selous-Niassa wildlife corridor, southern Tanzania...55 Table 17: Home range sizes of radio-tracked elephants in the Selous-Niassa Wildlife Corridor, as calculated with the minimum convex polygon, kernel and Jennrich- Turner methods...56 Table 18: Percentage of the total home range overlap of each radio-collared elephant with all other radio-collared elephants from the Selous-Niassa wildlife...59 iii

8 The Selous-Niassa Wildlife Corridor Table 19: Total distance travelled, maximum and average distance moved between successive tracking locations for elephants radio-collared in different areas of the Selous-Niassa wildlife corridor Table 20: Seasonal habitat preference of elephants in the Selous-Niassa wildlife corridor in southern Tanzania between December 2000 and September Table 21: Changes in habitat preference of elephants in the Selous-Niassa wildlife corridor in southern Tanzania between the wet and dry season...66 Table 22: Home range sizes of African elephants...75 iv

9 Figure Index FIGURE INDEX Figure 1: The Selous-Niassa ecosystem...3 Figure 2: The distribution of villages and roads in relation to the protected areas in and around the Selous-Niassa Wildlife Corridor in Tanzania and Mozambique. BZ: buffer zones around Selous are separate from the Game Reserve, around Niassa are part of the Game Reserve...12 Figure 3: Mean elephant calf: female ratios in six different survey areas of the Selous- Niassa Wildlife Corridor...26 Figure 4: Sizes of different age-sex classes in elephant groups in five different survey areas in the northern and central section of the Selous-Niassa Wildlife Corridor averaged over 5 years between 1997 and Adm-Adult male, Adf-Adult female.27 Figure 5: Sizes of different age-sex classes in elephant groups averaged across five different survey areas in the northern and central section of the Selous-Niassa Wildlife Corridor between 1997 and Adm-Adult male, Adf-Adult female...27 Figure 6: The relative frequency with which wildlife species were mentioned as being involved in crop raiding activities (n = 87) Figure 7: Shows the relationship between monthly crop damage by larger mammals and avarage rainfall pattern in Songea Rural District from 1990 to Figure 8: Bundles of snares collected from a single snare line by Game Assistant, Ally Msusa during fieldwork, in the southern section of the Selous Niassa Wildlife Corridor Figure 9: A trunk of a bull traumatized by snare on the southern section of the Selous- Niassa Wildlife Corridor. The wound was cleaned and treated by Oxytetracycline spray...37 Figure 10: The major elephant movement routes in the Selous-Niassa Wildlife Corridor in southern Tanzania, in relation to the location of roads, villages and local protected areas. Arrows indicate likely continuation of known route, but do not imply direction of movements by elephants. BZ: bufferzones around Selous are separate from the Game Reserve, around Niassa are part of the Game Reserves Figure 11: Tree diagram showing the Malimbani elephant route...45 Figure 12: Tree diagram showing the Nampungu ya Chakame elephant route...46 Figure 13: Tree diagram showing the Ritungula elephant route...48 Figure 14: Tree diagram showing the Sasawala-Lukumbule elephant route...49 Figure 15: Home ranges of nine radio-tracked elephants in relation to the locations of major elephant movement routes, villages and protected area boundaries in the Selous-Niassa Wildlife Corridor. BZ: bufferzones around Selous are separate from the Game Reserve, around Niassa are part of the Game Reserves...57 Figure 16: Cummulative observation area curve, illustrating the relationship between home range size and period of observation for six bull elephants radio-collared in the southern section of the Selous-Niassa Wildlife Corridor, Southern Tanzania...60 Figure 17: Cummulative observation area curves illustrating the relationship between home range size and period of observation in two elephants radio-collared in the northern section of the Selous-Niassa Wildlife Corridor, Southern Tanzania...60 Figure 18: Tracking locations of three radio-collared elephants in the northern section of the Selous-Niassa Wildlife Corridor (Arrow on the small map insert)...62 Figure 19: Tracking locations of three radio-collared elephants in the central section of the Selous-Niassa Wildlife Corridor (Arrow on the small map insert)...63 v

10 The Selous-Niassa Wildlife Corridor Figure 20: Tracking locations of three radio-collared elephants in the central and southern section of the Selous-Niassa Wildlife Corridor (Arrows on the small map insert)...64 Figure 21: One of the signboards showing where the SNWC (Malimbani Route) Crosses the Songea-Tunduru main road between Mchomoro and Kilimasera in Songea Rural District (Namtumbo). Four such signs have been placed in places identified as important elephant crossing areas along the main road to alert people not to carry out activities that will prevent elephant movements vi

11 Abbreviations ABBREVIATIONS AP ALT AST CBC DRDP EDTA GIS GPS GTZ Hb IZW MCP NAF NGR PCV RBC SCP SGR SNWC SODA SUA TAWIRI VEO VGS WBC WMA Alkaline Phosphatase Alanine AminoTransferase Aspartate Amino Transferase Community Based Conservation District Rural Development Programme Ethylene Diamine Tetraacetic Acid Geographical Information System Global Position System German Agency for Technical Cooperation Haemoglobin Institute for Zoo and Wildlife Research, Berlin, Germany Minimum Convex Polygon (to determine a home range) Sodium Flouride Niassa Game Reserve Packed Cell Volume Red Blood Cells Selous Conservation Programme Selous Game Reserve Selous-Niassa Wildlife Corridor Songea Development Action (predecessor of Songea DRDP) Sokoine University of Agriculture, Morogoro, Tanzania Tanzania Wildlife Research Institute, Arusha, Tanzania Village Executive Officer Village Game Scout White Blood Cells Wildlife Management Area (on village land) vii