Challenges during the research process and possible sources of error

made from mistakes. Multiple models were made for each species to find the optimal variables for each model. Also, the dataset had to be edited several times when mistakes and errors were realized. These errors included modelling conflicts involving all the predatory species together and not separating crop damage from human damages in case of human-elephant conflicts. New models

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were made with separate data for each, which resulted in more accurate models. Removing parts of the data because of the electrical fence on the border Tsavo West National Park, was also done after first modelling with data spanning from 2014 to 2016. In the final models, only data prior to

September 2015 was chosen for the models due to the fence being completed at the time. Leaving the data could have possibly biased the analysis.

Some of the algorithms used in SDM have tendency to overfit to the data and its impacts are possibly not noticed if data is spatially autocorrelated. Spatial autocorrelation is usually present in spatial data, also in this study. All the explanatory variables were spatially autocorrelated, at least at short distances. SDM is seen to overcome the problem of overfit by evaluating the results.

However, when testing data is obtained by cross-validation, there is possibility that the testing data is not independent from training data due to spatial autocorrelation. This evokes healthy scepticism towards the models, but the majority vote prediction maps were made to adjust potential bias and inaccuracies of single models.

Land cover was not used as an explanatory variable for its insignificance for the models. However, the land cover data resolution was 300 meters compared to 100 meters of other explanatory

variables. As it is possible that the agroecological zones of Taita Taveta County are strong

determinants in the distribution of HWC, land cover most likely has an impact on the HWCs but it was not discovered by the used models. The importance of land cover and possibly NDVI-land cover interactions should be considered for further studies on the topic.

HWC is very seasonal phenomenon following shifts in rainfall. Seasons impact the HWCs in

different ways as explained in previous sections. All the environmental variables used in the models are yearly averages and they do not take the seasonal changes into account. This is one of the deficiencies of the models that must be understood. Annual rainfall is not evenly distributed among the months of a year and also some of the rivers and water points are dry during the dry seasons. Hence, these explanatory variables are not completely realistic. An extension of this study could be trying to improve the models by adding temporal dimension to them. To compensate the missing temporal dimension of the models, the kernel density maps of the conflicts were made to see how much the distributions of HWCs change with the seasons.

The responses to distance to river and distance to water point variables behaved unexpectedly. There were significant differences between the species, between the models and between the two variables that should depict the same thing, water availability. These two variables were by far, the most problematic during the analysis. This was most likely due to the seasonal changes explained

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before. However, if the algorithms did not reach consensus about the impact of these variables, their effect on the majority vote prediction decreased.

The differences between the models and modelling runs were significant with many species. For this reason, it can be assumed that the models have not been certain on the selection of significant variables and the splits of cross validation have a significant impact on the results. However, 20 modelling runs were made for each species and the predictions of the risk zones were done by combining the predictions of the best five models in an attempt to take also this into account. What comes to the trustworthiness of the HWC data used in SDM, Kuronen explains in her master’s thesis (2016) that communities of Taita Hills are not eager to report all the conflicts experienced. However, during the fieldwork in the lowlands of Taita Taveta County, it was learned that all the HWC incidents experienced by the people I met were reported and compensation forms filled. Through this and the fact that the studied species do not reside in the higher elevations of Taita Hills, the data is considered as representative information about the phenomenon. Analysis of temporal distribution of HWCs (1990–2016) can be slightly biased because it is possible that the eagerness to report conflicts to KWS might have been low in the beginning of the 1990s because of bad relationship between the communities and the KWS. The relationship has improved since, as is the eagerness to report HWCs. However, this notion is impossible to know for sure and the whole data was used to estimate the temporal distribution of the HWCs by each species.