Taphonomy of Verreaux's Eagle (Aquila verreauxii) prey accumulations from the Cape Floral Region, South Africa: implications for archaeological interpretations

Abstract

We conducted a taphonomic analysis of modern prey accumulations of Verreaux's Eagle (VE; Aquila verreauxii) from the Cape Floral Region of South Africa. VE nest in or around cliffs and rocky outcrops, places that also attract other bone accumulators, including humans. Therefore, it is necessary to characterize the signatures of VE bone accumulation with as much precision as possible in order to differentiate between the prey remains of other bone accumulators, especially in relation to fossil assemblages that originate in and around cliffs, rock shelters, and caves. Towards this end, we describe the taxonomic composition, skeletal-part representation, bone breakage patterns, and bone surface modifications of mammal bones as well as the range of variability within those signatures. Based on the frequency of bone modifications we determine that VE modify the bones of their prey more often than do other eagle species. We suggest that taphonomic patterns derived from predation by other eagle taxa are not the most appropriate means to identify VE predation in faunal assemblages. In addition, we conclude that there is patterned variability in the ways that VE accumulate and modify the bones of their prey. There are two distinct skeletal-parts preservation, bone breakage, and bone surface modification patterns among the prey in our sample: one that characterizes hyraxes, mole-rats, and carnivores, and another that characterizes hares and bovids. Faunal analysts investigating the potential role of VE at fossil sites should be aware of 1) these taphonomic patterns and differences and 2) that there is no singular pattern of accumulation. We define patterns of preservation, breakage, and bone modification that can be employed on a taxon-specific basis to distinguish VE prey remains from other bone accumulators.