Total Aerial Census of Elephants and Other Large Mammals in the Tsavo-Mkomazi Ecosystem
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TOTAL AERIAL CENSUS OF ELEPHANTS AND OTHER LARGE MAMMALS IN THE TSAVO-MKOMAZI ECOSYSTEM Shadrack Ngene1; Festus Ihwagi2; Martha Nzisa1; Joseph Mukeka3 Steve Njumbi4; and Patrick Omondi3 1Kenya Wildlife Service, Tsavo Conservation Area, P.O. Box 14 Voi, Kenya; 2Save the Elephants, P.O. Box 54667, Nairobi 00200, Kenya; 3Kenya Wildlife Service, Biodiversity Research and Monitoring, P.O. Box 40241, Nairobi 00100, Kenya; 4International Fund for Animal Welfare, P.O. Box 25499, Nairobi 00603, Kenya Sponsored by the International Fund for Animal Welfare and Kenya Wildlife Service AUGUST 2011 i TABLE OF CONTENTS TABLE OF CONTENTS ................................................................................................................................i LIST OF TABLES .......................................................................................................................................iii LIST OF FIGURES.........................................................................................................................................iv ILLUSTRATION.............................................................................................................................................vi ACKNOWLEDGEMENTS..........................................................................................................................................vii EXECUTIVE SUMMARY.............................................................................................................................ix GENERAL BACKGROUND .......................................................................................................................1 2. OBJECTIVES OF THE SURVEY............................................................................................................2 3. STUDY AREA ..............................................................................................................................................2 3.1 Location and area ....................................................................................................................................2 3.2 Rainfall ......................................................................................................................................................2 3.2. Geology and Soils...................................................................................................................................3 3.3 Habitat.......................................................................................................................................................3 3.4 Flora ..........................................................................................................................................................5 3.5 Fauna.........................................................................................................................................................5 4. METHODS....................................................................................................................................................5 4.1. Census Blocks design.............................................................................................................................5 4.2. Aircraft and crew....................................................................................................................................5 4.3. Data recording and cleaning .................................................................................................................7 4.4. Data analysis............................................................................................................................................7 5. RESULTS .......................................................................................................................................................8 5.1 Status and trends of elephants...............................................................................................................8 5.2 The distribution and density of elephants .........................................................................................10 5.3 Elephant carcasses and carcass ratio ..................................................................................................15 5.4 The status and distribution of buffalo................................................................................................18 5.5 Status, density and distribution of giraffe ..........................................................................................22 5.6 The status, density and distribution of common zebra ...................................................................25 5.7 The status, density and distribution of lesser kudu..........................................................................30 5.8 The status and distribution and density of cattle and shoats..........................................................32 5.9 The distribution and density of other species...................................................................................33 i 5.10 Distribution of settlements and mining activities...........................................................................33 5.11 Illegal activities.....................................................................................................................................42 6. DISCUSSIONS ...........................................................................................................................................44 6.1 Elephant number, density and distribution.......................................................................................44 6.2 Elephant carcasses and carcass ratios.................................................................................................44 6.3 Buffalo numbers, density and distribution ........................................................................................45 6.4 Hartebeest, Grant’s gazelle and Thomson’s gazelle.........................................................................45 6.5 Livestock.................................................................................................................................................46 6.6 Settlements and mining ........................................................................................................................47 6.7 Illegal activities.......................................................................................................................................47 7. CONCLUSIONS AND RECOMMENDATIONS .............................................................................48 7.1 Conclusions............................................................................................................................................48 7.2 Recommendations.................................................................................................................................48 8. REFERENCES ...........................................................................................................................................49 9 APPENDICES .............................................................................................................................................52 Appendix 1. A sample data sheet..........................................................................................................53 Appendix 2. Counting hours, scanning rates per block and crew members ..................................54 Appendix 3. Species codes used in recording data.............................................................................56 Appendix 4. List of participants in 2011 Tsavo-Mkomazi Ecosystem total elephant count .......57 Appendix 5. Number of elephant carcasses in Tsavo-Mkomazi ecosystem (1991-2011). ...........59 ii LIST OF TABLES TABLE 1. NUMBER OF ELEPHANTS COUNTED IN TSAVO-MKOMAZI ECOSYSTEM FROM 1962-2011......9 TABLE 2. NUMBER OF ELEPHANTS AND ELEPHANT CARCASSES COUNTED IN TSAVO-MKOMAZI ECOSYSTEM FROM 1988 TO 2011. OLD CARCASSES ARE CALCULATED BY SUBTRACTING TOTAL DEAD FROM RECENT DEAD.THE OLD CARCASSES INCLUDE VERY OLD AND OLD CARCASSES WHEREAS RECENT CASES INCLUDE FRESH AND RECENT CARCASSES. ..............................................15 TABLE 3. THE NUMBER OF BUFFALO COUNTED IN THE TSAVO-MKOMAZI ECOSYSTEM IN 7-12 FEBRUARY 2011........................................................................................................................................19 TABLE 4. THE NUMBER OF BUFFALO COUNTED IN THE TSAVO-MKOMAZI ECOSYSTEM IN 7-12 FEBRUARY 2011. DATA ON GIRAFFE FOR 2002 IS MISSING...............................................................22 TABLE 5. THE NUMBER OF COMMON ZEBRA COUNTED IN THE TSAVO-MKOMAZI ECOSYSTEM IN 7-12 FEBRUARY 2011........................................................................................................................................26 iii LIST OF FIGURES FIGURE 1. A MAP SHOWING THE COUNTING BLOCKS USED DURING THE 7-12 FEBRUARY 2011 AERIAL COUNT OF ELEPHANTS AND OTHER LARGE MAMMALS IN THE TSAVO-MKOMAZI ECOSYSTEM ....4 FIGURE 2. A MAP SHOWING THE FLIGHT LINES USED DURING THE 7-12 FEBRUARY 2011TSAVO- MKOMAZI AERIAL COUNT. .......................................................................................................................6 FIGURE 3. TOTAL COUNT ESTIMATES OF TSAVO ELEPHANTS FROM 1988 TO 2011. THE NUMBER OF ELEPHANTS INCREASED FROM ABOUT 6,399 IN 1988 TO ABOUT 12,573 IN 2011, WHICH IS ABOUT 96% INCREASE............................................................................................................................................8