Taphonomy of Yellow-legged Gull (Larus michahellis) pellets from the Chafarinas islands (Spain)

Abstract

Fish are consumed by many predators in addition to humans. Identifying the agent responsible for an archaeological fish bone accumulation is a crucial yet far from straightforward task in the absence of diagnostic criteria. It is for this reason that exploring the features of fish bone collections produced by animals constitutes a key issue of archaeozoological research. In this paper, one such study is presented for the Yellow-legged Gull (Larus michahellis J.F. Naumann, 1840). A total of 48 pellets were collected in a colony of the species on two islands of the Chafarinas archipelago (Mediterranean Sea). The analyses demonstrate that fish remains, represented by 13 species and 1 genus, made up 93% of the 2789 identified remains. Most assemblages were dominated by the European pilchard (Sardina pilchardus (Walbaum, 1792)). Our study indicates that digestive processes modify skeletal elements through abrasion and fragmentation. Based on the modifications that were recorded, a set of diagnostic criteria is proposed to serve as proxies for spotting fish bone deposits produced by Yellow-legged Gulls on archaeological assemblages.