The scarabaeidae dung beetles of the Aberdare National Park, Republic of Kenya: ecosystem services and factors affecting diversity and abundance.

Stanbrook, Roisin (2018) The scarabaeidae dung beetles of the Aberdare National Park, Republic of Kenya: ecosystem services and factors affecting diversity and abundance. Doctoral thesis (PhD), Manchester Metropolitan University.

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Abstract

Dung beetles are a species group highly lauded for their sensitivity to land use change and their ecosystem service provision. There are few studies of the dung beetle communities found in Afromontane forests despite the fact these forests form part of a global hotspot of biodiversity. I sampled the dung beetle community in six habitats across an altitudinal gradient in the Aberdare National Park in central Kenya using standardised trapping methods. This study provides insight on the distribution, diversity and abundance of dung beetles and sheds new light on how dung beetle abundance and distribution respond to biotic and abiotic changes in Afromontane ecosystems. It has also identified that fluctuations in abundance occur in accordance with both elevation and habitat variability. The interspecific response sensitivity to even slight modifications in habitat type has facilitated the identification of eight potential ecological indicator species and showed that gradients in their population response (abundance) reflect overall preference for open vegetation or closed canopy forests within the Aberdare National Park. Due to their biogeographical history and specialisms the dung beetles of the Aberdare National Park may be particularly negatively affected by temperature increases associated with global warming for two reasons. Firstly, 50% of the variation in dung beetle species richness is attributable to mammal abundance, the presence of herbivores plus the distance between sampling points; and secondly, there is both intra- and interspecific variation in elevational placement and habitat preference of species and individuals. The results of this study have important conservation implications. This study underscores the importance of conserving as much habitat heterogeneity in mountain ecosystems as possible. Differences in dung beetle diversity and species richness between habitat types are manifest and the high turnover of species between altitude bands means that all locations within the ANP should be afforded equal protection.