Contemporary fire regimes and elephant impacts in Baikiaea-dominated woodlands of the Chobe region, northern Botswana
Othusitse Lekoko A B * , Jeremy Russell-Smith B , Andrew Edwards B and Cameron Yates BA
B
Abstract
Savanna ecosystems constitute approximately 20% of the Earth’s terrestrial surface and are increasingly under threat from various factors including effects of climate change. In Baikiaea plurijuga-dominated woodlands of Botswana, the combination of destructive fire regimes and large elephant populations has been cited as a major cause of adverse vegetation changes in African savanna and woodland systems.
We assessed the status of fire regimes in Botswana’s premium wildlife eco-tourism Chobe region to determine whether market-based fire management could be applied to support broader ecological fire management and employment outcomes.
The methods used were: (1) reconstructed fire regimes from the early 1990s coinciding with the cessation of commercial timber exploitation; (2) combined automated MODIS 250 m and manually derived Landsat 30 m burn scar products to generate a 33-year Fire Frequency Index (FFI); (3) classified regional vegetation structural types derived from a 5-year (2021–2024) early dry season Landsat median image; and (4) assessed dry season elephant population density distributions in relation to fire occurrence.
Frequent (on average, one in every 2.5 years) and relatively severe late dry season fires were characteristic in more open-canopied legume-dominated savannas and grasslands in the eastern sector of the project area. Elephant distributions in the dry season were independent of fire occurrence. Wildfires plausibly cause relatively greater impacts to Baikiaea-dominated vegetation macro-structure than elephants.
Multiple factors including national fire exclusion policy contribute to contemporary fire patterning in the Chobe regional landscape.
We suggest that carbon market-based approaches have potential for contributing to ecologically sustainable fire management and local employment opportunities.
Keywords: Baikiaea plurijuga, carbon markets, Chobe, elephant impacts, fire management, forest management, Miombo, savanna, wildlife conservation.
References
Andela N, Morton DC, Giglio L, Chen Y, Van Der Werf GR, Kasibhatla PS, Defries RS, Collatz GJ, Hantson S, Kloster S, Bachelet D, Forrest M, Lasslop G, Li F, Mangeon S, Melton JR, Yue C, Randerson JT (2017) A human-driven decline in global burned area. Science 356, 1356-1362.
| Crossref | Google Scholar | PubMed |
Anderson G, Walker B (1974) Vegetation composition and elephant damage in the Sengwa Wildlife Research Area, Rhodesia. South African Journal of Wildlife Research 4, 1-14.
| Google Scholar |
Archibald S, Scholes RJ, Roy DP, Roberts G, Boschetti L (2010) Southern African fire regimes as revealed by remote sensing. International Journal of Wildland Fire 19, 861-878.
| Crossref | Google Scholar |
Archibald S, Staver AC, Levin SA (2012) Evolution of human-driven fire regimes in Africa. Proceedings of the National Academy of Sciences of the United States of America 109, 847-852.
| Crossref | Google Scholar | PubMed |
Barnes ME (2001) Effects of large herbivores and fire on the regeneration of Acacia erioloba woodlands in Chobe National Park, Botswana. African Journal of Ecology 39, 340-350.
| Crossref | Google Scholar |
Ben-Shahar R (1993) Patterns of elephant damage to vegetation in northern Botswana. Biological Conservation 65, 249-256.
| Crossref | Google Scholar |
Ben-Shahar R (1996a) Do elephants over-utilize mopane woodlands in northern Botswana? Journal of Tropical Ecology 12, 505-515.
| Crossref | Google Scholar |
Ben-Shahar R (1996b) Woodland dynamics under the influence of elephants and fire in northern Botswana. Vegetatio 123, 153-163.
| Crossref | Google Scholar |
Ben-Shahar R, Macdonald DW (2002) The role of soil factors and leaf protein in the utilization of mopane plants by elephants in northern Botswana. BMC Ecology 2, 3.
| Crossref | Google Scholar | PubMed |
Beuchner H, Dawkins HC (1961) Vegetation change induced by elephants and fire in Murchison Falls National Park, Uganda. Ecology 752-766.
| Crossref | Google Scholar |
Breiman L (2001) Random forests. Machine Learning 45, 5-32.
| Crossref | Google Scholar |
Bussière E, Potgieter D (2023) KAZA Elephant Survey 2022. Results and Technical Report. Kasane, Botswana. https://www.kavangozambezi.org.
Cassidy L, Perkins J, Bradley J (2022) Too much, too late: fires and reactive wildfire management in Northern Botswana’s forests and woodland savannas. African Journal of Range & Forage Science 39(1), 160-174.
| Crossref | Google Scholar |
Chevallier R (2016) State of Community-based Natural Resource Management in Southern Africa: Assessing Progress and Looking Ahead. South African Institute of International Affairs (2016) Stable https://www.jstor.org/stable/resrep28378. 20.500.12592/4br8bx
Childes S, Walker B (1987) Ecology and dynamics of the woody vegetation on the Kalahari sands in Hwange National Park, Zimbabwe. Vegetatio 72, 111-128.
| Crossref | Google Scholar |
Coughenour MB, Ellis JE (1993) Landscape and climatic control of woody vegetation in a dry tropical ecosystem: Turkana District, Kenya. Journal of Biogeography 20, 383-398.
| Crossref | Google Scholar |
Desanker PV, Frost P, Justice C, Scholes R (1997) The Miombo Network: framework for a terrestrial transect study of land-use and land-cover change in the Miombo ecosystems of central Africa. In ‘Conclusions of the Miombo Network Workshop’. December 1995, Zomba, Malawi. https://www.cabidigitallibrary.org/doi/full/10.5555/19991905916
Dube OP (2013) Challenges of wildland fire management in Botswana: towards a community inclusive fire management approach. Weather and Climate Extremes 1, 26-41.
| Crossref | Google Scholar |
Dube OP (2024) Global wildfire activity re-visited. Global Environmental Change 89, 102894.
| Crossref | Google Scholar |
du Toit JT, Moe SR, Skarpe C (2014). Elephant‐mediated ecosystem processes in Kalahari‐Sand woodlands. In ‘Elephants and Savanna Woodland Ecosystems: A Study from Chobe National Park’. (Eds C Skarpe, JT du Toit, SR Moe) pp. 30–39. (John Wiley & Sons, Ltd: Botswana) 10.1002/9781118858615.ch3
Dziba L, Ramoelo A, Ryan C, Harrison S, Pritchard R, Tripathi H, Sitas N, Selomane O, Engelbrecht F, Pereira L (2020) Scenarios for just and sustainable futures in the miombo woodlands. In ‘Miombo Woodlands in a Changing Environment: Securing the Resilience and Sustainability of People and Woodlands’. (Eds NS Ribeiro, Y Katerere, PW Chirwa, IM Grundy) pp. 191–234. (Springer) 10.1007/978-3-030-50104-4
Eames T, Vernooij R, Russell-Smith J, Yates C, Edwards A, Van Der Werf GR (2023) Division of the tropical savanna fire season into early and late dry season burning using MODIS active fires. International Journal of Applied Earth Observation and Geoinformation 125, 103575.
| Crossref | Google Scholar |
Edwards A, Hauser P, Anderson M, Mccartney J, Armstrong M, Thackway R, Allan G, Hempel C, Russell-Smith J (2001) A tale of two parks: contemporary fire regimes of Litchfield and Nitmiluk National Parks, monsoonal northern Australia. International Journal of Wildland Fire 10, 79-89.
| Crossref | Google Scholar |
Evans J, Russell-Smith J (2019) Delivering effective savanna fire management for defined biodiversity conservation outcomes: an Arnhem Land case study. International Journal of Wildland Fire 29, 386-400.
| Crossref | Google Scholar |
FAO (2020) ‘Global Forest Resources Assessment: Main Report.’ 1st edn. (FAO: Rome, Italy) 10.4060/ca9825en
Fox JT, Vandewalle ME, Alexander KA (2017) Land cover change in northern botswana: the influence of climate, fire, and elephants on semi-arid savanna woodlands. Land 6, 73.
| Crossref | Google Scholar |
Grace J, José JS, Meir P, Miranda HS, Montes RA (2006) Productivity and carbon fluxes of tropical savannas. Journal of Biogeography 33, 387-400.
| Crossref | Google Scholar |
Guy P (1981) Changes in the biomass and productivity of woodlands in the Sengwa Wildlife Research Area, Zimbabwe. Journal of Applied Ecology 507-519.
| Crossref | Google Scholar |
Holdo RM (2005) Stem mortality following fire in Kalahari sand vegetation: effects of frost, prior damage, and tree neighbourhoods. Plant Ecology 180, 77-86.
| Crossref | Google Scholar |
Holdo RM (2006) Elephant herbivory, frost damage and topkill in Kalahari sand woodland savanna trees. Journal of Vegetation Science 17, 509-518.
| Crossref | Google Scholar |
Holdo RM (2007) Elephants, fire, and frost can determine community structure and composition in Kalahari woodlands. Ecological Applications 17, 558-568.
| Crossref | Google Scholar | PubMed |
Humphrey GJ, Gillson L, Ziervogel G (2021) How changing fire management policies affect fire seasonality and livelihoods. Ambio 50, 475-491.
| Crossref | Google Scholar | PubMed |
Keeley JE, Rundel PW (2005) Fire and the Miocene expansion of C4 grasslands. Ecology Letters 8, 683-690.
| Crossref | Google Scholar |
Kgathi DL, Sekhwela MBM (2012) Sustainability of the commercial exploitation and mangement of the Chore Forest Reserves in Botswana. South African Geographical Journal 85, 26-34.
| Crossref | Google Scholar |
Klop E, Prins HH (2008) Diversity and species composition of West African ungulate assemblages: effects of fire, climate and soil. Global Ecology and Biogeography 17, 778-787.
| Crossref | Google Scholar |
Laws RM (1970) Elephants as agents of habitat and landscape change in East Africa. Oikos 1-15.
| Crossref | Google Scholar |
Lipsett-Moore GJ, Wolff NH, Game ET (2018) Emissions mitigation opportunities for savanna countries from early dry season fire management. Nature Communications 9, 2247.
| Crossref | Google Scholar | PubMed |
Mapaure IN, Campbell BM (2002) Changes in miombo woodland cover in and around Sengwa Wildlife Research Area, Zimbabwe, in relation to elephants and fire. African Journal of Ecology 40, 212-219.
| Crossref | Google Scholar |
McNaughton S (1985) Ecology of a grazing ecosystem: the Serengeti. Ecological Monographs 55, 259-294.
| Crossref | Google Scholar |
Mmolotsi RM, Obopile M, Kwerepe BC, Sebolai B, Rampart MP, Segwagwe AT (2012) Studies on Mukwa (Pterocarpus angolensis, DC) Dieback in Chobe Forest Reserves in Botswana. Journal of Plant Studies 1(2),.
| Crossref | Google Scholar |
Mosugelo DK, Moe SR, Ringrose S, Nellemann C (2002) Vegetation changes during a 36‐year period in northern Chobe National Park, Botswana. African Journal of Ecology 40, 232-240.
| Crossref | Google Scholar |
O’connor TG, Puttick JR, Hoffman MT (2014) Bush encroachment in southern Africa: changes and causes. African Journal of Range & Forage Science 31, 67-88.
| Crossref | Google Scholar |
Pellegrini AF, Pringle RM, Govender N, Hedin LO (2017) Woody plant biomass and carbon exchange depend on elephant‐fire interactions across a productivity gradient in African savanna. Journal of Ecology 105, 111-121.
| Crossref | Google Scholar |
Pettinari M, Lizundia-Loiola J, Chuvieco E (2021) ESA CCI ECV fire disturbance: D4. 2.1 product user guide—MODIS, version 1.1. https://climate.esa.int/en/projects/fire/key-documents/
Phan TN, Kuch V, Lehnert LW (2020) Land cover classification using Google Earth Engine and random forest classifier—The role of image composition. Remote Sensing 12, 2411.
| Crossref | Google Scholar |
Pricope NG, Binford MW (2012) A spatio-temporal analysis of fire recurrence and extent for semi-arid savanna ecosystems in Southern Africa using moderate-resolution satellite imagery. Journal of Environmental Management 100, 72-85.
| Crossref | Google Scholar | PubMed |
Ramo R, Roteta E, Bistinas I, Van Wees D, Bastarrika A, Chuvieco E, Van Der Werf GR (2021) African burned area and fire carbon emissions are strongly impacted by small fires undetected by coarse resolution satellite data. Proceedings of the National Academy of Sciences 118, e2011160118.
| Crossref | Google Scholar | PubMed |
Ribeiro NS, Shugart HH, Washington-Allen R (2008) The effects of fire and elephants on species composition and structure of the Niassa Reserve, northern Mozambique. Forest Ecology and Management 255, 1626-1636.
| Crossref | Google Scholar |
Ribeiro NS, Katerere Y, Chirwa PW, Grundy IM (2020a) ‘Miombo Woodlands in a Changing Environment: Securing the Resilience and Sustainability of People and Woodlands.’ (Springer Nature) 10.1007/978-3-030-50104-4
Ribeiro NS, Silva De Miranda PL, Timberlake J (2020b). Biogeography and Ecology of Miombo Woodlands. In ‘Miombo Woodlands in a Changing Environment: Securing the Resilience and Sustainability of People and Woodlands’. (Eds NS Ribeiro, Y Katerere, PW Chirwa, IM Grundy) pp. 9–53. (Springer International Publishing) 10.1007/978-3-030-50104-4
Rodriguez-Galiano VF, Ghimire B, Rogan J, Chica-Olmo M, Rigol-Sanchez JP (2012) An assessment of the effectiveness of a random forest classifier for land-cover classification. ISPRS Journal of Photogrammetry and Remote Sensing 67, 93-104.
| Crossref | Google Scholar |
Roteta E, Bastarrika A, Padilla M, Storm T, Chuvieco E (2019) Development of a Sentinel-2 burned area algorithm: generation of a small fire database for sub-Saharan Africa. Remote Sensing of Environment 222, 1-17.
| Crossref | Google Scholar |
Russell-Smith J, Yates C, Vernooij R, Eames T, Van Der Werf G, Ribeiro N, Edwards A, Beatty R, Lekoko O, Mafoko J, Monagle C, Johnston S (2021) Opportunities and challenges for savanna burning emissions abatement in southern Africa. Journal of Environmental Management 288, 112414.
| Crossref | Google Scholar | PubMed |
Russell-Smith J, Yates C, Vernooij R, Eames T, Lucas D, Mbindo K, Banda S, Mukoma K, Kaluka A, Liseli A (2024) Framework for a savanna burning emissions abatement methodology applicable to fire-prone miombo woodlands in southern Africa. International Journal of Wildland Fire 33, WF23193.
| Crossref | Google Scholar |
Sankaran M, Hanan NP, Scholes RJ, Ratnam J, Augustine DJ, Cade BS, Gignoux J, Higgins SI, Le Roux X, Ludwig F, Ardo J, Banyikwa F, Bronn A, Bucini G, Caylor KK, Coughenour MB, Diouf A, Ekaya W, Feral CJ, February EC, Frost PG, Hiernaux P, Hrabar H, Metzger KL, Prins HH, Ringrose S, Sea W, Tews J, Worden J, Zambatis N (2005) Determinants of woody cover in African savannas. Nature 438, 846-849.
| Crossref | Google Scholar | PubMed |
Smith AM, Wooster MJ, Drake NA, Dipotso FM, Falkowski MJ, Hudak AT (2005) Testing the potential of multi-spectral remote sensing for retrospectively estimating fire severity in African Savannahs. Remote Sensing of Environment 97, 92-115.
| Crossref | Google Scholar |
Stoldt M, Göttert T, Mann C, Zeller U (2020) Transfrontier conservation areas and human-wildlife conflict: the case of the Namibian component of the Kavango-Zambezi (KAZA) TFCA. Scientific Reports 10, 7964.
| Crossref | Google Scholar | PubMed |
Thomson P (1975) The role of elephants, fire and other agents in the decline of a Brachystegia boehmii woodland. South African Journal of Wildlife Research 5, 11-18.
| Google Scholar |
Timberlake J, Chidumayo E (2011) Miombo Ecoregion Vision Report. Occasional Publications in Biodiversity. WWF SARPO, Harare, Zimbabwe. https://library.wur.nl.
Trapnell CG (1959) Ecological results of woodland and burning experiments in Northern Rhodesia. The Journal of Ecology 47, 129-168.
| Crossref | Google Scholar |
Trisos C, Adelekan I, Totin E, Ayanlade A, Efitre J, Gemeda A, Kalaba K, Lennard C, Masao C Mgaya Y (2022) Africa. Climate Change 2022: Impacts, Adaptation and Vulnerability. In ‘Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change’. (IPCC Secretariat: Switzerland) http://www.ipcc.ch
van der Sluis T, Cassidy L, Brooks C, Wolski P, Vanderpost C, Wit P, Henkens R, Van Eupen M, Mosepele K Maruapula O (2017) Chobe district integrated land use plan. Wageningen Environmental Research, Report 2813. 182 pp. Available at www.wur.nl/environmental-research
van der Werf GR, Randerson JT, Giglio L, Van Leeuwen TT, Chen Y, Rogers BM, Mu M, Van Marle MJ, Morton DC, Collatz GJ (2017) Global fire emissions estimates during 1997–2016. Earth System Science Data 9, 697-720.
| Crossref | Google Scholar |
White F (1983) ‘The vegetation of Africa: a descriptive memoir to accompany the UNESCO/AETFAT/UNSO vegetation map of Africa.’ Vol. 20. p. 356. (UNESCO: Paris, France) 10.5555/19840692540