Phoretic oribatids (Acari, Oribatida) as bird bioindicators? Insights from the site of Tabacalera (Gijón, N. Spain, 6th-7th centuries AD).

Bird remains are rare on archaeological sites yet often crucial to address a multitude of questions, both cultural and biological. In this paper we argue that oribatid mites living on bird feathers, scales and nests may prove useful to infer not only bird presence but occasionally their breeding at a given site in the absence of their remains. Although oribatids are for all purposes stationary, a good number of species practice non-parasitic phoresis on birds that allows the mites to disperse over large distances. The specificity of the interrelationship, thus the quality of the bioindicator signal, is probably time-dependent, so that the longer the more specific the link between the vertebrate and the arthropod becomes. Oribatids are useful bioindicators because of the intensive sclerotization of their exoskeleton that insures their preservation in archaeological deposits. In this paper inferences about the bird assemblage retrieved at the Early Medieval site of Tabacalera (Gijón, Spain) are explored from the standpoint of the phoretic oribatids recovered in the deposits. [ABSTRACT FROM AUTHOR]