Variation in aardvark (Orycteropus afer) burrow use between natural and agricultural sites in the Bronkhorstspruit-Middelburg region, South Africa

Abstract

Aardvark (Orycteropus afer) burrows provide shelter to a variety of organisms, making it important to understand how these engineered environments get utilized in areas that are affected by agricultural activities. To address this, camera traps were used to record the use of abandoned aardvark burrows by other species at two sampling sites in the Bronkhorstspruit-Middelburg region in South Africa: a natural site (Telperion Nature Reserve) and a transformed site (pastoral fields of a grain farm and grazing paddocks). Data from traps placed in front of 36 burrows over a five-week period were analysed in R-Studio using generalized Linear Models (GLMs), Generalized Linear Mixed Models (GLMMs) and Chi-square tests to test whether there were any differences in the response variables between Telperion and the farm. Response variables included species richness, encounter frequency, burrow proximity, activity duration and activity times. In total 37 species were observed throughout the study of which 13 species were found at both sites, specifically nine mammal and four bird species. Whilst no statistically significant difference in species richness was found, differences in spatial dispersion between sites were observed for some species, possibly due to habitat preferences and/or human activities. Furthermore, the results of encounter frequency show that some species occur more frequently at Telperion, while others occur more frequently at the farm, possibly due to historical hunting and current poaching at the farm, in combination with habitat sensitivity and resource availability. Although no notable differences in activity times and duration were found for any of the species between sites, some species showed slight alterations in how they spent their time at the burrows which suggests that agricultural activity may have a minimal impact on these aspects of species behaviour. The results confirm that aardvark burrows may provide shelter, and foraging opportunities for numerous species living within agricultural environments in this region and highlight the conservation opportunities that these spaces represent. Efforts and funding to preserve keystone species, such as aardvark, and the burrows they engineer, should incorporate both farming and protected settings to be effective.