Competition between people and elephants in the Okavango Delta Panhandle, Botswana

The general objective of this study was to gain a greater understanding of the complexities of the competition between people and elephants, focusing on elements that can be investigated in the short term and could aid in devising effective mitigation and management strategies. Specifically, I aimed to a) determine the current elephant population numbers and growth rate in the study area and investigate how reliable aerial survey estimates are; b) monitor the extent of human-elephant conflict (HEC) incidents and compare community based monitoring techniques to a top-down government approach; c) determine key drivers of elephant crop-raiding and explore how spatial autocorrelation affects such data; d) investigate how elephant movements are affected by human habitat modifications, and; e) investigate rural farmers' attitudes towards elephants and compare perceived human-elephant conflict to actual measurable levels of elephant crop damage. My findings show that combinations of social and ecological factors are involved in shaping competition between people and elephants. A multi-disciplinary approach to investigations is, therefore, needed to fully understand such competition and resulting conflicts. Contributory factors to HEC identified in this study include: actual and perceived conflict levels; farmer vulnerability to risk and available coping strategies; susceptibility of crops to elephant foraging, which affects both actual and perceived conflict levels; methods used to measure damage; natural and modified behaviour of people and elephants affecting resource and spatial use as well as how each species reacts to living in close proximity to each other; and human feelings and perception towards elephants and the situation, which are influenced by an array of socio-economic factors. To be successful, effective conflict resolution and management strategies will, therefore, require consideration of short and long term dynamics, as well as a combination of mitigation approaches that consider all elements affecting conflict extent

Competition between people and elephants in the Okavango Delta Panhandle, Botswana

The general objective of this study was to gain a greater understanding of the complexities of the competition between people and elephants, focusing on elements that can be investigated in the short term and could aid in devising effective mitigation and management strategies. Specifically, I aimed to a) determine the current elephant population numbers and growth rate in the study area and investigate how reliable aerial survey estimates are; b) monitor the extent of human-elephant conflict (HEC) incidents and compare community based monitoring techniques to a top-down government approach; c) determine key drivers of elephant crop-raiding and explore how spatial autocorrelation affects such data; d) investigate how elephant movements are affected by human habitat modifications, and; e) investigate rural farmers' attitudes towards elephants and compare perceived human-elephant conflict to actual measurable levels of elephant crop damage. My findings show that combinations of social and ecological factors are involved in shaping competition between people and elephants. A multi-disciplinary approach to investigations is, therefore, needed to fully understand such competition and resulting conflicts. Contributory factors to HEC identified in this study include: actual and perceived conflict levels; farmer vulnerability to risk and available coping strategies; susceptibility of crops to elephant foraging, which affects both actual and perceived conflict levels; methods used to measure damage; natural and modified behaviour of people and elephants affecting resource and spatial use as well as how each species reacts to living in close proximity to each other; and human feelings and perception towards elephants and the situation, which are influenced by an array of socio-economic factors. To be successful, effective conflict resolution and management strategies will, therefore, require consideration of short and long term dynamics, as well as a combination of mitigation approaches that consider all elements affecting conflict extent.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Understanding farmers' reasons behind mitigation decisions is key in supporting their coexistence with wildlife

Coexistence between wildlife and farmers can be challenging and can endanger the lives of both, prompting the provisioning of mitigation methods by governments and non-governmental organizations (NGOs). However, provision of materials, demonstration of the effectiveness of methods or willingness to uptake a method do not predict uptake of methods. We used ethnographic decision models to understand how farmers' work through the decisions of uptake or non-uptake of methods to mitigate crop consumption by elephants, and how the government and NGOs can either enable or impede the ability of farmers to protect themselves and their crops. While farmers were motivated to use methods if they received or could afford to buy materials and they believed in the effectiveness of the methods, they still did not use them if they considered a method to be dangerous, or issues with elephants not to be severe enough, or when the supply of materials or income was not sufficient. Methods were not even considered by farmers if they lacked awareness or knowledge of the method. Government departments and NGOs enabled farmers to mitigate elephant crop consumption by providing opportunities for cash income, and providing materials and knowledge. Yet, there was disparity between the materials farmers received and methods they wished to adopt. One-off inputs of materials did not result in sustainable use of mitigation methods. We see an opportunity for governmental departments or NGOs to stimulate logistics (e.g. roads and retail) to increase availability of mitigation materials since this promoted farmer autonomy. We also highlight the importance of empowering farmers by facilitating within community sharing of mitigation ideas and increasing knowledge about the effectiveness of promising wildlife conscious farming, as despite promising farmer testimonies, only a few farmers used these techniques.</p

Bayesian tracer mixing models and isotope data elephant diet

In the supplementary information we explain why we did not use Bayesian tracer mixing models in the final paper. Isotope data: We air-dried the faecal and vegetation samples in an air-drying cabinet. After transportation, we dried samples for a further 24 h at 70 °C and ground to pass through a 1 mm mesh at the Okavango Research Institute laboratory. Samples were then shipped to the stable isotope laboratory housed in the archaeology department at the University of Cape Town, South Africa. There they were weighed in to tin cups to an accuracy of 1 mg on a Sartorius M2P microbalance.Sample weights were 2.5 mg for samples with potentially low nitrogen content, 2.1–2.2 mg for legumes and agricultural samples and 2.3 mg for other sample types. Samples were combusted in a Flash 2000 elemental analyser interfaced to a Delta V Plus isotope ratio mass spectrometer (IRMS) via a Conflo IV gas control unit (Thermo Scientific,Bremen, Germany). The in-house standards used were: Sucrose(“Australian National University (ANU)”sucrose), MG (Merck Gel), Acacia (Acacia saligna, Glencairn). All the in-house standards were calibrated against IAEA (International Atomic Energy Agency) standards,either at UCT or by other labs. Nitrogen was expressed in terms of its value relative to atmospheric nitrogen, while carbon was expressed in terms of its value relative to Pee-Dee Belemnite (VPDB).In our analyses we use stable isotopic values from faeces and their association to isotopic values of most likely consumed browse and grass species as proxies for elephant diet. In reality, diet content can vary from isotopic content due to issues as fractionation of isotopes during digestion, this is why we correct the results with fractionation values (Codron and Codron, 2009)

Timing of dietary switching by savannah elephants in relation to crop consumption

Tree and grass quality on the African savannah shows seasonal variation, driving mixed-feeding herbivores to switch between browsing and grazing. During this switch, crop consumption could be an attractive alternative to browsing. We analysed elephant diet variability in the Okavango Delta, Botswana, using faecal stable isotope ratios of carbon (δ^13C) and frequencies of elephant crop consumption, to determine the extent to which crop consumption relates to this potential switch. Although elephants did increase their relative grass consumption in the wet season, browse dominated the annual diet. After February, the proportion of grass in the diet dropped considerably, and continued decreasing through April when farmers reported most crop consumption. Generalized Linear Models revealed that the occurrence of elephant crop consumption increased with the proportion of grass consumed and with decreasing grass quality. The proportion of grass in elephant faeces increased with increasing crop consumption intensity. As crop consumption could also be related to nutrient deficiencies in elephant diet, we calculated the total dietary input of nutrients to reveal potential deficiencies. Elephant diet contained insufficient levels of sodium year-round, and insufficient phosphorus from February to July. As the latter coincides with the timing of crop consumption, we consider our results an indication that phosphorus –and potentially sodium - deficiencies, could play a role in elephant dietary choices, including crop consuming behaviour. Further experimental research is required to show whether supplying elephants with supplementary phosphorus and sodium sources could reduce this micro-nutrient deficiency, and could play a role in reducing elephant crop consumption.</p

Understanding farmers' reasons behind mitigation decisions is key in supporting their coexistence with wildlife

1. Coexistence between wildlife and farmers can be challenging and can endanger the lives of both, prompting the provisioning of mitigation methods by governments and non-governmental organisations (NGOs). However, provision of materials, demonstration of the effectiveness of methods or willingness to uptake a method do not predict uptake of methods. 2. We used Ethnographic Decision Models to understand how farmers' work through the decisions of uptake or non-uptake of methods to mitigate crop consumption by elephants, and how the government and NGOs can either enable or impede the ability of farmers to protect themselves and their crops. 3. While farmers were motivated to use methods if they received or could afford to buy materials and they believed in the effectiveness of the methods, they still did not use them if they considered a method to be dangerous, or issues with elephants not to be severe enough, or when the supply of materials or income was not sufficient. Methods were not even considered by farmers if they lacked awareness or knowledge of the method. Government departments and NGOs enabled farmers to mitigate elephant crop consumption by providing opportunities for cash income, and providing materials and knowledge. Yet, there was disparity between the materials farmers received and methods they wished to adopt. 4. One-off inputs of materials did not result in sustainable use of mitigation methods. We see an opportunity for governmental departments or NGOs to stimulate logistics (e.g. roads and retail) to increase availability of mitigation materials since this promoted farmer autonomy. We also highlight the importance of empowering farmers by facilitating within community sharing of mitigation ideas and increasing knowledge about the effectiveness of promising wildlife conscious farming, as despite promising farmer testimonies, only a few farmers used these techniques