Advantages and disadvantages of using social information for carcass detection – a case study using white-backed vultures

Utilizing social information during foraging, wherein individuals observe how others interact with their environment rather than relying solely on individually acquired information, is a widely used strategy across the animal kingdom. Nevertheless, our understanding of how different environments shape the extent of social information use remains limited. Here, we assessed the advantages and disadvantages of contrasting foraging strategies in different environments in terms of vulture and carcass density, at the individual, population and ecosystem level. We built an agent-based model to simulate three foraging strategies of African white-backed vultures in Namibia: nonsocial, local enhancement, and chains of vultures. This model incorporated field-derived parameters including vulture and carcass density, and flight characteristics of foraging vultures. From the model outputs, we calculated searching efficiency, competition for resources, and scavenging efficiency and compared the results with observed field data. The results highlight social foraging strategies as overall more advantageous than the nonsocial strategy. The chains of vultures strategy outperformed local enhancement only in terms of searching efficiency under high vulture densities. Furthermore, our findings suggest that vultures in our study area likely adopt diverse foraging strategies influenced by variations in vulture and carcass density. The model developed in this study is potentially applicable beyond the specific study site, rendering it a versatile tool for investigating diverse species and environments. Exploring the role of social foraging holds significant implications for the long-term sustainability of populations and ecosystem processes.