First description of red-backed shrike Lanius collurio food caching in Central Italy: prey’s type and spatial position into the larders

Abstract

The food storage and the use of impaling or wedging the preys in larders is a typical behaviour of true shrikes. In this study we present the preliminary results about this behaviour of red-backed shrikes in Central Italy, where this behaviour was rarely recorded. We focused on the larders description, prey composition and spatial pattern of prey fixation in the larder. Our results are the first data about this particular behaviour in Italy since 1933 and highlighted the importance that it could have also as signalling function of territoriality. Our results showed that the main vegetal support used was Prunus spinosa L., used also for impale the heavier prey (micromammals, reptiles and birds). The invertebrate constituted 78% of items in the larders, with vertebrate prey in the rest. The height from ground where prey is impaled was correlated with shrub height, but the concealment level was independent from prey type.