Carrion type and extent of breeding success together influence subsequent carrion choice by adult burying beetles

Insects can adjust their behaviour in relation to experience in a wide range of contexts including foraging, mate selection and choice of oviposition site. Here, we investigate whether burying beetles Nicrophorus vespilloides modulate their choice of carrion type in relation to the outcome of their past breeding experience. Burying beetles require the carcass of a small vertebrate, such as a mouse or a chick, to reproduce. Beetle parents convert this carrion into an edible nursery for their larvae, whom they typically care for throughout larval development. We tested whether a beetle's past breeding experience influenced its subsequent choice of carrion when presented simultaneously with either a dead mouse or a dead chick. We found that beetles that bred on a mouse and produced many larvae in their first breeding attempt subsequently favoured mice over chicks for their second breeding attempt. Beetles that had produced fewer larvae on a dead mouse switched to favouring dead chicks in their second breeding attempt. Those that had bred on a dead chick chose carrion at random subsequently, regardless of their previous breeding success. Our general conclusion is that burying beetles can integrate different sources of information about their past breeding experience with current cues when selecting carrion for reproduction. How do burying beetles choose a carcass to breed on? In step 1, each beetle pair was given a chick or a mouse carcass for reproduction. In step 2, each individual beetle was given a choice between a chick and a mouse carcass. Beetles that produced a higher density of larvae on mice in step 1 were more likely to choose mice in step 2. Beetles bred on chicks in step 1 chose carrion at random in step 2.