The geomorphic work of the European mole and its role as an ecosystem engineer. A case study from Oxfordshire, southern England.

Moles (small insectivorous mammals of the family Talpidae) are widespread across the Northern Hemisphere, with their ranges covering Europe, Asia, and North America. The presence of these subterranean mammals is easily detected through the mounds, or molehills, which they construct as surface bioproducts of tunnel systems excavated underground. These bioconstructions created by moles indicate they may play geomorphologically important roles in sediment systems. The bioturbation of soils by moles has also been shown to be ecologically important as they mix nutrients and aerate soils, suggesting that their role in local sediment systems may be intrinsically linked to ecosystem functioning. However, compared to other fossorial animals (species which dig, e.g. ants, rabbits, badgers etc.) the impact of moles as direct and indirect biogeomorphic agents and their role as ecosystem engineers is poorly understood. For instance, relatively little is known about the impact of moles on microtopography, surface runoff and erosion rates, vegetation cover, and soil properties.

By examining molehills created by the European mole (Talpa europaea) in Oxfordshire, UK, we provide a quantitative assessment of how these landforms evolve over time and space. Following the mapping of molehills at selected sites and regular monitoring over a 6-month period, this study estimates the rate of sediment movement caused by mole activity. We also examine what happens to molehill morphology post-construction, as well as the characteristics of soil bioturbated by moles vs. non-bioturbated soil and the potential impact of molehills on local biodiversity.