Estimating the Dispersal Ability of the Carrion Beetle <i>Necrodes littoralis</i> (Coleoptera: Staphylinidae: Silphinae) by Mark‐Recapture

ABSTRACT Understanding the dispersal ability of insects is critical for conservation efforts, as well as for preventing economic and health risks, such as the spread of bluetongue disease or African swine fever (ASF). However, knowledge of the dispersal ability of a wide range of insect species is limited. One highly unpredictable resource in space and time is carcasses, which provide an ephemeral habitat for the necrophilous insect community. In 2021 and 2022, we marked more than 5000 specimens of the carrion beetle Necrodes littoralis (L. 1758, Coleoptera: Staphylinidae: Silphinae) and released them within a forested landscape with experimentally placed cadavers to test two hypotheses. Our first question was how far N. littoralis could disperse; we hypothesised that the beetles are highly mobile and disperse over more than 3 km, which is the distance currently used for buffer strips around wild boar carcasses infected by ASF. Our second question was if wind affected the colonisation of cadavers by N. littoralis . As beetles locate carrion using olfactory cues, we hypothesised that the probability of cadaver colonisation by insects increases when positioned up‐wind. Based on recapture rates of 4%–7% per year, we estimated a mean distance between release and carrion of 6 km using a dispersal kernel. Some individuals were recaptured at distances exceeding 30 km. The probability of colonising an experimental cadaver increased when the resource was placed up‐wind, but colonisation probability did not increase consistently over both years with the body mass of the carcasses. Our findings support previous work suggesting high dispersal ability of the carrion beetle N. littoralis , as an adaption to colonising highly ephemeral necromass resources. From a conservation perspective, these results suggest that there are limited dispersal barriers for carrion insects within a management region. From the perspective of disease control, however, these results also indicate that buffer strips of 3 km, as used in ASF mitigation, may not be sufficient to prevent the spread of pathogens by insects.