Exploring geological and pedological factors as potential drivers of the Great Wildebeest Migration in the Serengeti ecosystem, N-Tanzania (East Africa)

Project Summary

Wildebeest grazing in the central Serengeti, Oct 2019
Wildebeest grazing in the central Serengeti, Oct 2019 E. Eckmeier

The aim of this project is to study the interplay between geological processes and nutrient availability in soils and plants as long-term drivers for the Great Wildebeest Migration in the Serengeti National Park, Tanzania, one of the largest seasonal ungulate migrations in the world. The Serengeti ecosystem is located in a unique geological setting. Soils in this region form on a complex patchwork of highly depleted basement rocks, interspersed with young soils affected by active tectonics and volcanism of the East African Rift. The roles of climatic and biological drivers of the wildebeest migration, like seasonal rainfall and vegetation dynamics, as well as anthropogenic factors have been intensively studied. However, the underlying causes, long-term drivers and stabilizers of seasonal animal movements remain not well known. Especially the effects of rock chemistry and weathering processes at the rock-soil interface are poorly understood.

Soil sampling on grassland in the southeastern Serengeti plains. Soils are influenced by frequent input of carbonatitic volcanic ash from nearby Ol Doinyo Lengai volcano
Soil sampling on grassland in the southeastern Serengeti plains. Soils are influenced by frequent input of carbonatitic volcanic ash from nearby Ol Doinyo Lengai volcano S. Kübler

Previous studies carried out in the southern and central Kenya Rift in close vicinity to the Serengeti ecosystem showed systematic correlations between rock chemistry and soil nutrient levels (Kübler et al., 2015, 2016, 2021), influencing grazing patterns of wildlife and livestock in this region. We thus hypothesize that the geological complexity of the East African Rift System and related patchiness of soil properties play a key role in the heterogeneity of nutrients vital for animal health and growth in the wider Serengeti ecosystem. Detailed field campaigns including sampling and analysis of rocks, soils and vegetation along the established migration corridors of wildebeest combined with satellite remote sensing analysis will help us to better understand the underlying drivers of large scale animal movements in this region.

 

Sheet erosion on heavily overgrazed soils developed on Archean basement rocks in the central Serengeti National Park
Sheet erosion on heavily overgrazed soils developed on Archean basement rocks in the central Serengeti National Park S. Kübler

 

The 2019 field-work crew
The 2019 field-work crew S. Kübler

In Sep/Oct 2019 we had the opportunity to carry out a field campaign in the Serengeti National Park. Our objectives were to establish collaborations with scientists from the Nelson Mandela African Institute of Science and Technology (NM-AIST) and National Museums of Kenya (NMK) and to carry out reconnaissance mapping and locate potential sampling locations for rocks, soils and vegetation to examine geological and pedological processes that might play an important role in controlling annual movements of wildebeest and other migratory species in this ecosystem.

 

 

Project members
Dr. Simon Kübler (Ludwig-Maximilian University Munich)
Dr. Stephen Rucina (National Museums of Kenya)
Akida Meya (Nelson Mandela African Institute of Science and Technology)
Prof. Dr. Eileen Eckmeier (CAU)

Project related publications
Kübler, S., Rucina, S., Aßbichler, D., Eckmeier, E., King, G., (2021). Lithological and Topographic Impact on Soil Nutrient Distributions in Tectonic Landscapes: Implications for Pleistocene Human-Landscape Interactions in the Southern Kenya Rift. Frontiers in Earth Science 9, 103. https://doi.org/10.3389/feart.2021.611687

Kornei, K. (2020). Geology and chemistry drive animal migration in the Serengeti, Eos 101. https://doi.org/10.1029/2020EO144423.

Eckmeier, E., Kübler, S., Meya, A., Mathai Rucina, S. (2020). The role of geology and climate in soil nutrient variability-potential drivers for large ungulate migrations in the Serengeti ecosystem (Northern Tanzania, East Africa), EGU General Assembly Conference Abstracts (p. 13969).

Kübler, S., Rucina, S., Reynolds, S., Owenga, P., Bailey, G., King, G.C.P. (2016). Edaphic and Topographic Constraints on Exploitation of the Central Kenya Rift by Large Mammals and Early Hominins. Open Quaternary 2: 5, 1–18. http://doi.org/10.5334/oq.21

Kübler, S., Owenga, P., Reynolds, S.R., Rucina, S., King, G.C.P. (2015). Animal movements in the Kenya Rift and evidence for the earliest ambush hunting by hominins. Nature Scientific Reports 5, 14011. http://doi.org/10.1038/srep14011